iws fabrication application.pdf

IIW/EWF Diploma - Fabrication and Application (Foundation)

FAA1

Training & Examination Services Granta Park, Great Abington Cambridge CB21 6AL, UK

Copyright TWI Ltd

Rev 3 August 2010 Contents

Copyright TWI Ltd 2010

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IIW/EWF Diploma - Fabrication and Application (Foundation) Contents Section Subject Pre training briefing 1 Quality Assurance and Quality Control 1.1 Definitions 1.2 Quality system standards 1.3 Auditing and documentation 1.4 Quality requirements for welding 1.5 Calibration/validation of welding equipment 1.6 Workshop exercise 1.7 Questions on validation and in-process monitoring 2 Approval Testing 2.1 Welder approvals BS.EN.287 2.2 Training 2.3 Definitions 2.4 Codes of practice and application standards 2.5 Other welding approval standards 2.6 Questions on approval testing and quality control 2.7 Practical on procedure and welder qualification testing 2.8 Questions on welding procedure and welder approvals 2.9 Practical exercise on codes of practice and application standards 3 Development of Residual Stress and Distortion 3.1 Factors effecting residual stresses and distortion 3.2 Typical material properties 3.3 Characteristics of materials which determine the amount of distortion

and residual stresses 3.4 Correcting distortion 3.5 Questions 4 Plant Facilities and Equipment 4.1 Factory layout 4.2 Joint fit-up and jigging 4.3 Positioning equipment 4.4 Questions



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5 Safety in the Welding Shop 5.1 Arcs 5.2 Hot metal 5.3 Fire 5.4 Noise 5.5 Cables 5.6 Mechanical hazards 5.7 Filter glasses 5.8 Electrical 5.9 Gas cylinders 5.10 Fumes and gasses 5.11 Parent metal 5.12 Surface coating 5.13 Air 5.14 Ventilation 5.15 Other protective measures 5.16 Recommendations for specific processes 5.17 Questions 6 Economics of Welding 6.1 Deposition rate 6.2 Consumable efficiency 6.3 Arc time duty cycle 6.4 Joint design 6.5 Downtime 6.6 Questions 7 Non-Destructive Testing (NDT) 7.1 Visual testing 7.2 Penetrant testing 7.3 Magnetic particle inspection (MP) 7.4 Eddy current testing (ET) 7.5 Ultrasonic testing (UT) 7.6 Radiographic testing (RT) 7.7 Visual inspection 7.8 NDT Methods 7.9 Comparison between X and gamma sources 7.10 Radiological protection 7.11 Choice of method 7.12 NDT clarification schemes 7.13 PCN personal certification in NDT 7.14 Standards and specifications 7.15 Questions



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8 Repair by Welding 8.1 Introduction 8.2 Types of defects 8.3 General techniques for typical repairs 8.4 Groove shape 8.5 Welding processes 8.6 Summary 8.7 Questions 9 Typical Exam Practice Question 10 Additional information: Welding consumables storage and

handling 11 Additional information: Preheat and interpass temperature

equipment and control 12 Additional information: weld defects/imperfections

Section 1 Quality Assurance and Quality Control

Rev 3 September 2010 Quality Assurance and Quality Control


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1 Quality Assurance and Quality Control 1.1 Definitions

Before we consider what quality assurance and quality control is, let us first define quality. This is best described as being the fitness-for-purpose of a product, service or activity. BS 7448 Part 1 Quality Vocabulary, describes quality as the totality of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs. Quality assurance is all those planned and systematic actions necessary to provide adequate confidence that a product or service will satisfy given requirements for quality. Quality control is described as the operational techniques and activities that are used to fulfil requirements for quality. Quality assurance is therefore the documented plans and systems by which confidence in a product is provided and comprises all of the paperwork systems that are used to plan, control and record activities, ie the documentation. Quality control is those activities which monitor the quality of the product. The operational techniques of checking materials, dimensional checks, inspection before, during and after welding, non-destructive testing, hydraulic or leak testing, ie activities which take place after the event and which check that a specified activity has been carried out correctly. Quality assurance has been introduced to ensure that the activity is right first time on the principle that prevention is better than cure. This can be achieved by planning and anticipating problems. In order to satisfy this requirement a documented quality system is needed which sets out in a formal framework the basis of control for the critical activities. This framework in general, comprises of four tiers of documentation. The highest tier being the company quality manual, cascading down through quality systems, quality plans and detailed manufacturing and inspection instructions.

1.1.1 Quality system Can be defined as: The organisation structures, responsibilities, procedures, processes and resources for implementing quality management.

The quality manual and support procedures document an organisation's quality system.



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1.1.2 Quality manual Can be defined as: A document setting out the general quality policies, procedures and practices of an organisation.

The word general, is important in this definition. The quality manual is usually the first indication a purchaser or prospective client has of a company's approach to quality. This document should contain a statement of the company's total commitment to quality by means of a quality policy statement signed by the Chairman, MD or Chief Executive of the company. This policy statement should be prominently displayed within the company.

1.1.3 Procedure Can be defined as: A document that describes how an activity is to be performed and by whom.

Note: The definitions used above are based on those given in British Standards:

BS 7448: Part 1: ISO 8402: Quality Vocabulary Internal terms. BS 4778: Part 2: Glossary of terms used in quality assurance.

Note, that a procedure is not a detailed work instruction such as a welding procedure but a statement of who does what and how, it describes the corporate plan for achieving quality. But there may be times when an organisation needs to operate in a different way from the corporate system, for example, for a unique project or to satisfy a specific customer's requirements.

In these circumstances an appropriate quality system can be documented in the form of a project off-contract specific quality plan.

1.1.4 Quality plan Can be defined as: A document setting out the specific quality practices, resources and sequence of activities relevant to a particular product, service, contract or project. A quality plan is the corporate quality system suitably modified to reflect specific equipments. It may compromise a project quality manual incorporating appropriate sections from the corporate quality manual which apply. It is generally a detailed document.



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Project procedures may well include: Existing procedures appropriate to the contract. Existing procedures amended for the contract. New procedures to meet specific requirements for the contract. Some contracts may well call for a combination of all three.

1.2 Quality system standards Quality system standards specify the minimum requirements of quality systems for application to specific products or services. Standards are normally used for the following purposes: As guidance to an organisation introducing quality assurance. As a basis for evaluating an organisation's quality system (assessment). To specify the quality assurance requirements when invoked in a

contract. The standard common in the UK is ISO 9000.

1.2.1 Quality Records A quality record is any document that indicates the inspection performed, quantities inspected, results obtained, positive identification of the material inspected to drawing or part number, the signature or stamp of the person carrying out the inspection and date of inspection. Quality records might also indicate the qualification of personnel, calibration of equipment or other records not directly related to the product. Questions that need to be addressed include: What quality records are to be maintained, eg receiving inspection reports, NDT results, test certificates, final inspection reports and non-conformance reports (including any feedback or corrective action generated). Where are the records filed and by whom? How long are the quality records retained? Are the quality records available to the customer for analysis and

review? Are records easily retrievable? Is a suitable environment available to minimise deterioration or damage

to stored records?



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1.2.2 Typical quality record contents The Quality Record Package for a welded product will be defined specifically for a contract but should include the following types of information: a) Records of stage inspections in the form of check sheets or quality plans. b) Non-conformity reports and concession records. c) Where appropriate, As built drawings. d) Welding procedures. e) Welder approvals. f) Welding consumable records. g) Weld history records. h) NDT reports. i) Heat treatment records. j) Hydraulic and/or other testing records. k) Where appropriate, material test certificates. l) Final acceptance certificates.

1.2.3 What areas of a business need to be covered by ISO 9000? This standard requires the following elements of the business to have set procedures. Management responsibility - who is responsible for what? Quality system - how does the system operate? Contract review, allows personnel to see what the requirement is and

who has been asked to do what. Design review and control, ensure smooth passage from drawing board

to end product. Documentation controls, make sure the correct documents are available. Purchasing, make sure we have the right products and services. Purchaser supplied product, make sure that these items are also OK. Product identification and traceability, what is it and where is it? Process control, lets everyone know clearly how to make the product. Inspection and test, describes how to inspect and test it. Inspection, measuring and test equipment, make sure the equipment

used is correct.



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Inspection and test status, where is the product in the inspection cycle? Control of non-conforming product, ensures incorrect product is not

used. Corrective action, find the root cause of the problem and solve it. Handling, storage, packing and delivery, don't damage it now it's made. Quality records, the need is for documented evidence that the company

meet specific requirements. Internal quality audits, are quality activities performing as planned? Training, it cannot be manufactured effectively if people are not

adequately trained and qualified. Servicing, if carried out by the company, effective procedures are

required. Statistical techniques, use them to build-in product quality.



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Quality Programme Documentation



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The Welding Inspector Responsibilities

Ensure compliance to standard or code

Ensure welding criteria by policing work and

documentation

Ensure workmanship

Honesty integrity

Attributes

Literacy Fitness Physical Eyesight

Duties

Observe measure identify

Before welding

During welding

After welding

Material Consumables

Welding processes Joint fit-up

Preheat Tack welding/clamping

Alignment Calibration

Safety

Voltage Amperage

Travel speed Interpass temperature

Interpass cleaning

PWHT Visual assessment NDT assessment

Accept Reject

Collect and collate all documents which may

include: Code or standard

material certificates Consumable certificates Calibration certificates

Drawing(s) Welding procedure

Approval certificates Inspection records

PWHT records Other test records

Concessions Compliance certificates

Concession Repair

ID area Mark out Remove Re-weld

Re-inspect

Acceptance of the product

Inspector passes the document package to a higher authority for final

approval



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1.3 Auditing and documentation Quality manuals, procedures and work instructions, etc provide the objective evidence that the systems of control have been adequately planned. The records and documentation generated by carrying out work in accordance with these systems provides the evidence that the systems are being followed by all. Systems of control, no matter how effective they are, will tend to deteriorate because of human errors, such errors being perpetuated or because of changes in the nature of the business. In order to ensure that the systems are being followed and are effective and to determine if changes are needed it is necessary to monitor them. This is achieved by auditing the system and reviewing the results of the audit in order to implement any changes.

1.3.1 What is an audit? Quality audits examine a quality system for adequacy and correct implementation. They are defined in BS 4778 Part 1 as: Systematic and independent examinations to determine whether quality activities and related results comply with planned arrangements and whether these arrangements are implemented effectively and are suitable to achieve objectives. Auditing is carried out to provide objective evidence that the system is working in accordance with the procedures. When an audit is complete the results are analysed by management who must ensure that the quality policy is satisfied and modify the quality system if necessary.

1.3.2 Which type of audit? There are two depths of audit: A systems audit which is quite shallow and simply examines the system to confirm that it follows the quality manual and that procedures are in place. A Compliance audit, which is an in depth audit examining compliance with procedures.

1.3.3 Auditing of documentation A documentation audit is regarded as being a compliance audit, where documentation is examined in depth. Items to check in such an audit should include: Is all the documentation available? Is the documentation schedule in accordance with contract or

specification requirements?



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Does the documentation itself comply with contract or specification requirements? For example, are weld procedure and welders correctly qualified?

Is it the correct material composition? Is the documentation legible? Have all the interested parties eg inspection department, independent

third party inspectors and client inspectors, signed off where required? Have provisions been made for storage? Which includes the ability to

retrieve documents and the storage conditions to prevent deterioration? Documentation audits should be carried out by the manufacturer/supplier as a matter of course. Customers will also frequently require access to carry out their own audits. Remember that no job is finished until the paperwork is complete. Failure of a documentation audit carried out by a client will often result in a delay in payment, even though the component may have been delivered to the client. There can often be a consequential financial penalty.

1.4 Quality requirements for welding Within the international community, welding has been confirmed as a special process which means that it will require to be controlled by specialist management and utilise specialist personnel. The welding co-ordination (ISO 14731) and the welding quality systems standards (ISO 3834) have been prepared in support of this ruling. It is perceived that these standards will be references in other application standards and will be used as set criteria for the qualification of fabricators. Currently there are a number of European Standards or codes that refer to ISO 3834 EN 13445:2002 unfired pressure vessels. prEN 15085: Railway applications Welding of Railway vehicles and

components. Pr EN 1090 Execution of steel structures. EN 12732: 2000 Gas supply systems Welding steel pipework

functional requirements. EN 12592: 2001 Water tube boilers and auxiliary installations. National Structural Steelwork Specification for Building Construction (5th

Edition), (NSSSBC ). It is also becoming more common for a requirement that the fabricator has a quality system compliant with ISO 3834 to be specified as a condition of the customer contract.



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1.4.1 Qualification of welding fabricators - ISO 3834 This is in five parts. Part 1 - Guidance for use describes how the standard works. Part 2 - Quality requirements for welding - Fusion welding of metallic materials - Comprehensive quality system. This standard is suitable for use by a manufacturer or an assessment body, as a supplement to ISO 9001 or 9002 providing detailed guidance on the requirements needed to be in place to adequately control welding. Part 3 - Quality requirements for welding, Fusion welding of metallic materials, Standard quality system. This standard can be applied where a documented quality system for the control of welding is required but which will not be used in conjunction with ISO 9001 or 9002. Part 4 - Quality requirements for welding - Fusion welding of metallic materials - Elementary system. This standard provides criteria appropriate for the control of welding when neither or the following conditions apply: A quality system according to ISO 9000 is not to be applied. The combination of selected welding processes, procedures and the final

welds are such that documented welding control have minor importance in respect to the overall integrity of the product.

Part 5 - Documents with which it is necessary to conform to claim conformity to the quality requirements of ISO 3834-2, ISO 3834-3 or ISO 3834-4 This lists all of the other documents or standards that are required for compliance with ISO 3834 such as sspecification and qualification of welding procedures and approval testing of welders, etc. The manufacturer should select one of the three parts from 2-4 specifying different levels of quality requirements, based on the following criteria related to products: The extent and significance of safety-critical products; The complexity of manufacture; The range of products manufactured; The range of different materials used; The extent to which metallurgical problems may occur; The extent to which manufacturing imperfections, e.g. misalignment,

distortion or weld imperfection, affect product performance. This approach offers a cascading qualification, for example, part 2 (comprehensive) also gives compliance for lower levels.



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As previously stated, It is intended that BS EN ISO 3834 complements, rather than conflicts with, quality systems established to meet the requirements of ISO 9000 and in the case of a comprehensive quality system for welding fabrication (part 2), requires additionally to ISO 9000 that specific procedures are used to control the following: 1 Review of requirements. 2 Technical review. 3 Sub-contracting. 4 Welders and welding operators. 5 Welding co-ordination personnel. 6 Inspection and testing personnel. 7 Production and testing equipment. 8 Equipment maintenance. 9 Description of equipment. 10 Production planning. 11 Welding procedure specifications. 12 Qualification of welding procedures. 13 Batch testing of consumables (if required by contract). 14 Storage and handling of welding consumables. 15 Storage of parent material. 16 Post-weld heat treatment procedure. 17 Inspection and testing before, during and after welding. 18 Non-conformance and corrective actions. 19 Calibration or validation of measuring, inspection and testing equipment. 20 Identification during process (if required by contract). 21 Traceability if required no specific requirement (if required by contract). 22 Quality records (if required by contract). A company applying for certification to ISO 3834 will usually be required to follow certain stages such as follows: Client returns preliminary enquiry. Quotation. Detailed forms sent to client. Assessment team appointed by auditor. Preliminary visit by auditor (not mandatory but usual) to carry out a gap

analysis. Document review by auditor to review procedures against ISO 3834. On site assessment conducted by auditor to demonstrate that the client

has accrued evidence that procedures are used and that these are overseen by the welding co-ordination team.

Assessment recommendations made. Certificate issued (5 year validity). Surveillance (yearly). This process, from application to certificate issue, can take months to complete.



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1.4.2 Welding co-ordination A key part of ISO 3834 is in the definition of responsibilities of the welding co-ordination personnel. ISO 14731 defines these personnel and the technical knowledge that they require. The main role falls to the Responsible Welding Co-ordinator (RWC). One or more personnel in a company may perform the welding co-ordination function but each part of the requirements of ISO 3834 listed above will require input from the welding co-ordination team. Table 1 in ISO 14731 gives guidance to those tasks, which may require a welding co-ordinator input. The technical knowledge required by the co-ordinator will obviously depend upon the complexity of the product. The standard defines three levels of knowledge and experience: 1 Comprehensive: Equivalent to the level of an International/European Welding Engineer. 2 Specific: Equivalent to the level of an International/European Welding Technologist. 3 Basic: Equivalent to the level of an International/European Welding Specialist. It can be seen that the three levels of technical knowledge defined imply a matching with the three levels of quality requirements required from parts 2 to 4 of ISO 3834. The IIW route is not mandatory; there are in fact three possible routes to demonstrate technical knowledge: IIW Qualification and experience (via interview). Interview to assess knowledge without IIW qualification (professional

review in 3834 Audit). Externally sub contract to an external subcontractor with appropriate

knowledge and experience, again an interview is required (it would be expected that external resource will be familiar with the company applying for certification and will be contracted to visit regularly).

1.5 Calibration/Validation of Welding Equipment Faulty equipment does not enhance the quality of work, it should follow that equipment used in production, or for welder and procedure approval tests, should be in a sound condition in all respects in order to avoid breakdown during production or testing. One important point to note is the accuracy of meters and the repeatability of the machine's controls in relation to output performance. Welding current connections and return leads on all arc welding equipment should be



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checked for tightness prior to commencing welding, failure to do so may lead to voltage losses affecting arcing conditions. Where semi-automatic gas shielded processes are used, care should be taken to ensure that the wire feeding systems are also repeatable and accurate. Additionally it would be expected that flowmeters controlling shielding and purging gases are calibrated. This activity is collectively known as validation A requirement in many industries during the welding operation is the use of a calibrated meter(s) to check welding current, arc voltages, travel speed and perhaps, wire feed speed. In addition, ensuring the welders are using the correct gas, the electrode wires are of the correct composition and that the preheat temperature and location have been correctly applied against the welding procedure requirements. In the case of Manual Metal Arc (MMA) and Submerged Arc Welding (SAW), attention should be paid to any special drying requirements for fluxes or covered electrodes and also the conditions they are kept in prior to use. A written procedure for storage and handling of consumables is recommended to be used and records of humidity and temperature may required to be kept. This activity is collectively known as in process monitoring.



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1.6 Workshop Exercise

1.6.1 Items to be checked during an audit on welding equipment From the power supply check: Mains input - connections - insulation - cable rating Produce your own checklist of the remaining items.



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1.6.2 Welding records (In-process monitoring) Welding records must include: Type of process (es). Identification of the materials and welding consumables. Identification of joint type(s) and fit-up. Welding procedures. Welder's identification and approval record. Inspection procedure and report identification. Defects found. Acceptance or rejection and to which acceptance levels. Corrective action taken.



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FAA1 Questions: Quality Assurance and Quality Control 1 Describe how the functions of QA, QC and inspection would operate in a small

sub-contract fabrication company.

2 How would these differ from the functions in a company, which also designs and

manufactures the product?

3 Describe the contents of a quality plan. Use a simple component/fabrication of your choice to illustrate your answer.

4 State the two types of audits that can be carried out.

5 List the personnel/departments that influence quality within a company.

6 What would be the function of a Welding Specialist in a fabrication organisation?



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1.7 Questions: validation and in-process monitoring

1 Briefly describe the different between calibration, validation and in-process monitoring.

2 Which of the following welding equipment can be validated and/or calibrated?

a. MMA transport power source without meters. b. TIG transformer-rectifier power source with meters. c. MIG/MAG inverted power source. d. Submerged-arc welding (mechanised). e. Resistance spot welder.

3 What are the tolerances specified for voltage and current values?

4 How frequently should validation be carried out?

5 You are required to monitor a critical welding procedure approval which involves the need for stringent heat input control. Briefly describe the equipment required to successfully complete this operation and provide a brief checklist on the details to ensure compliance.

1QUALITY ASSURANCE AND QUALITY CONTROL

TWI Training & Examinations ServicesCourse in Welding(EWF/IIW Diploma)

Quality

What is quality?What is quality?

Quality = degree to which a set of inherent Quality = degree to which a set of inherent characteristics fulfils explicit and implicit characteristics fulfils explicit and implicit requirementsrequirements

Quality - definitions

QualityQuality

ManagementManagementCoordinated activities to Coordinated activities to direct and control an direct and control an organisationorganisation

PolicyPolicy

Overall intentions and Overall intentions and direction of an organisation direction of an organisation related to quality as formally related to quality as formally expressed by top expressed by top managementmanagement

SystemSystemA system to direct and control A system to direct and control an organisation with regard to an organisation with regard to qualityquality

Quality management activities

QualityQuality

AssuranceAssurance

ControlControl

Part of quality management focused on Part of quality management focused on providing confidence that quality providing confidence that quality requirements will be fulfilledrequirements will be fulfilled

Part of quality management focused on Part of quality management focused on fulfilling quality requirementsfulfilling quality requirements

prevent defective workprevent defective workensure programme commitments ensure programme commitments are achievedare achievedprovide feedback to the provide feedback to the managementmanagement

Why do we need QA?Why do we need QA?

Quality assurance principle

Say what youSay what youre going to do (by re going to do (by writing procedures)writing procedures)

Do it Do it -- in compliance with in compliance with your own proceduresyour own procedures

Demonstrate that youDemonstrate that youve ve done itdone it

By keeping By keeping proper recordsproper records

By doing check By doing check auditsaudits

Quality assurance documents

Quality Quality assurance assurance documentsdocuments

SpecificationSpecification -- document stating document stating requirements (related to requirements (related to activities or products)activities or products)

Quality Quality manualmanual

-- document specifying the quality document specifying the quality management system of an management system of an organisationorganisation

Quality Quality planplan

-- document specifying which document specifying which procedures and resources shall be procedures and resources shall be applied by whom and when, to a applied by whom and when, to a specific projectspecific project

ProcedureProcedure -- specified way to carry out specified way to carry out an activityan activityCode of Code of practicepractice

-- a set of rules for a set of rules for manufacturing a specific manufacturing a specific product or activityproduct or activity

2Specification vs. procedureSpecification content:

Scope Applicable domain Terms and definitions Responsibilities Design requirements Material and/or process

requirements Inspection requirements

(including acceptance standards!)

Records

Procedure content: Scope Applicable domain Related documents

(standards, normative reference, procedures, etc)

Terms and definitions Responsibilities Procedure description Records

Quality in welding fabricationOrganisations that are involved in welding must

document their activities to show who is involved in welding decisions.

Design Material selection Procedure development and qualification Storage and issue of consumables Weld inspection PWHT and other special process survey Planning for welding

Those activities include but are not limited to:

Standards related to quality

ISO 9000 Quality ISO 9000 Quality systemsystem

EN 3834 EN 3834

Quality requirements for weldingQuality requirements for welding

EN 719/ISO 14731 EN 719/ISO 14731 Welding coordinationWelding coordination

EN 287 Approval EN 287 Approval testing of welderstesting of welders

EN ISO 15607 EN ISO 15607 Specification and Specification and

qualification of welding qualification of welding proceduresprocedures

EN 25817 (ISO EN 25817 (ISO 5817) Quality 5817) Quality

levelslevels

EN 473 EN 473 Qualification of NDT Qualification of NDT

personalpersonal

ISO 6520 ISO 6520 Classification of Classification of imperfectionsimperfections

ISO 9000 features

Provides a documented management system for quality assurance

Identifies welding as a special process (a process where the conformity of the resulting product cannot be readily verified)

Does not specify any welding requirements

Does not guarantee the welded product quality

Quality requirements for welding

EN 3834EN 3834--1 1 GuidelinesGuidelines

EN 729EN 729--2 2 Comprehensive Comprehensive

quality quality requirementsrequirements

EN 729EN 729--3 3 Standard quality Standard quality

requirementsrequirements

EN 729EN 729--4 4 Elementary quality Elementary quality

requirementsrequirements

For use when:For use when:You are accredited to ISO 9000Your products, materials, processes or procedures change frequentlyANDWelding quality is critical

For use when:For use when:Your materials, products, processes and procedures do not change frequentlyBUTWelding is an important process and weld quality is important

For use when:For use when:There are only very simple technical optionsWelding is an incidental joining processWeld quality is not crucial to product quality

EN 729/ISO 3834 requirements Part 2 Part 3 Part 4

Contract and design review M M NRSub contractor control M M NRWelder and procedure approval BOTH BOTH WELDER Inspection personnel M M MWelding co-ordination (EN719) M M NR Equipment (includes PPE) M R NR Production planning M M NR Consumable control M M MParent metal storage M M NR Post weld heat treatment M M NRWeld inspection M M NRNon-conformance & corrective action M M M Calibration M NR NRIdentification and traceability M M NR Quality records M M NR

M = mandatory R = recommended NR = not required

3Welding coordinator

His duties are stated in BS EN 14731 Welding coordination; task and responsibilities.

Welding coordinator: must be designated by employer is appointed by the company to issue/approve the

necessary welding documents must have demonstrated competence and

knowledge must have special technical knowledge the extent of knowledge is defined by employer job specification only if required by contract

All welding related tasks must be allocated to an AUTHORISED WELDING COORDINATOR

Competence in welding

Knowledge can be demonstrated at 3 levels:

comprehensive technical knowledge ie EWE specific technical knowledge ie EWT basic technical knowledge ie EWS

A welding coordinator MUST demonstrate technical competence i.e. he MUST be academicallyqualified in welding technology

Level depends on complexity of product and is usually determined by employer

But the client can specify the level in contract specification!

Welding coordinator activities contract review design review parent metal weldability, identification, handling, storage and

traceability consumables compatibility, identification, storage and handling subcontractor suitability production planning choosing the appropriate welding process, equipment

suitability, health and safety issues approval of welders/welding procedures welding operation supervision inspection/testing issuing documentation

Quality planIs a check list that specifies which procedures and Is a check list that specifies which procedures and associated resources shall be applied, by whom and when associated resources shall be applied, by whom and when to a specific project, product, process or contract. It to a specific project, product, process or contract. It contains:contains:

a list with the main operations following manufacturing sequencea list with the main operations following manufacturing sequencestop/hold points with specific requirements (e.g. document checkstop/hold points with specific requirements (e.g. document check, , NDT witnessed by customer representative, stamp check, NDT witnessed by customer representative, stamp check, independent body supervision, procedures used, acceptance independent body supervision, procedures used, acceptance standards, etc)standards, etc)type and number of documents issued (NDT report, WPAR, welder type and number of documents issued (NDT report, WPAR, welder qualification, dimension check list, etc)qualification, dimension check list, etc)name and signature of welding coordinator in charge with each name and signature of welding coordinator in charge with each operation (if required)operation (if required)date of completion for each stepdate of completion for each step

Quality planProcess Process

description description activityactivity

Responsible Responsible personperson

Process Process reference reference documentdocument

Approval Approval /remarks/remarks

HH

H H -- Hold point: work shall stop until representative are present toHold point: work shall stop until representative are present tomonitor/observe activitymonitor/observe activity

WW

W W -- Witness point: notifiable point; should representative fail to Witness point: notifiable point; should representative fail to attend, attend, work may proceedwork may proceed

RR

R R -- Document reviewDocument review

AA

A A -- Document approvalDocument approval

MM

M M -- Monitor/periodic control of activityMonitor/periodic control of activity

American standards related to quality

ISO 9000 Quality ISO 9000 Quality systemsystem

ASME I, III and VIII ASME I, III and VIII

Quality requirements for weldingQuality requirements for welding

EN 719/ISO 14731 EN 719/ISO 14731 Welding coordinationWelding coordination

ASME IX Approval ASME IX Approval testing of welderstesting of welders

ASME IX Specification ASME IX Specification and approval of and approval of

welding procedureswelding procedures

ASNT TCASNT TC--1A 1A Qualification of NDT Qualification of NDT

personalpersonal

AWS A3.0 AWS A3.0 Classification of Classification of imperfectionsimperfections

ASME I, VIII ASME I, VIII Quality levelsQuality levels

4ASME B&PV code

Product related requirementsProduct related requirementsBoilers Boilers -- Section ISection INuclear Nuclear -- Section IIISection IIIPressure vessels Pressure vessels -- Section VIIISection VIII

Material related Material related requirements requirements

Section IISection II

Ferrous material Ferrous material requirements requirements Section IIASection IIA

NonNon--ferrous material ferrous material requirementsrequirementsSection IIBSection IIB

Filler material Filler material requirements requirements Section IICSection IIC

NDE requirements NDE requirements (standard method) (standard method)

Section VSection V

Welding qualification Welding qualification & welder approval & welder approval

Section IXSection IX

Welding map

CC44

LL11

LL22

LL33

LL44

LL55CC11

CC22

CC33

CC55

CC66

NN11NN22 NN33

NN44

SS11SS22

Information's to be supplied:Information's to be supplied:weld type and positionweld type and position

WPS and PQR numberWPS and PQR number

type and extent of NDEtype and extent of NDE

welderwelders stamp numbers stamp number

type of PWHTtype of PWHT

Quality packa.k.a. doc pack, history docketa.k.a. doc pack, history docket

Quality pack Quality pack contentcontent

Documents supplied Documents supplied before commencement before commencement

of manufactureof manufacture

Documents supplied Documents supplied on completion of on completion of

constructionconstruction

Quality pack content

certificate of conformance with different codes/standards

design calculations (optional) manufacturing drawings WPS with supporting WPQR

(copies) welder qualifications qualification of NDT personnel NDT procedures PWHT oven calibration record

(optional)

material test certificates (list!) welding production tests (if

required) PWHT record (if required) NDT test reports: dimensional,

pressure test and coating thickness are included

quality plan and weld map as-built drawings non-conformity reports (SDR) operating/mounting instructions

Documents supplied before Documents supplied before manufacturemanufacture

Documents supplied after Documents supplied after manufacturemanufacture

Auditing

Definition: systematic, independent and documented process for obtaining evidence and evaluating it objectively to determine the extent to which criteria are fulfilled

AuditAudit

a systema system Is quite shallow; examines the system Is quite shallow; examines the system to confirm that it follows the quality to confirm that it follows the quality manual and procedures are in placemanual and procedures are in place

a compliancea complianceIt goes inIt goes in--depth; examines the compliance depth; examines the compliance with procedures and quality manualwith procedures and quality manual

Traceability Definition: Ability to trace the history, application or

location of that which is under considerationTraceability Traceability

can relate to:can relate to:

The origin of The origin of materials and materials and

partsparts

The The processing processing

historyhistory

The distribution and The distribution and location of the product location of the product

after deliveryafter delivery

Traceability - HOW? hard stamping painting/etching labelling

WHEN? Immediately after the operation!

5Conformity

RequirementRequirement

ConformityConformity

fulfilmentfulfilment

NonconformityNonconformity

nonnon--fulfilmentfulfilment

Corrective Corrective actionaction

RepairRepair ScrapScrap ConcessionConcession

ReleaseRelease

Nonconformity Nonconformity reportreport

Conformity evaluation

Test

determination of one or more characteristics according to a procedure

can be non-destructive or destructive

Conformity Conformity evaluationevaluation

Inspection

evaluation by observation and judgement

can be accompanied by measurement, testing or gauging

Inspection - terminology

detectable change in the material

signal from a discontinuity typical to the testing method used

DiscontinuityDiscontinuity

IndicationIndication

DetectionDetection

Acceptance Acceptance levellevel

EvaluationEvaluation

prescribed limit below which a component is accepted

Recordable Recordable indicationindication DEFECTDEFECT

1MEASUREMENT, CONTROL AND RECORDING IN WELDING

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Measuring in welding

Parameters to be measured: welding current arc voltage travel speed shielding gas flow rate

The purposes The purposes of measuringof measuring

Demonstration of Demonstration of conformance to conformance to

specified requirementsspecified requirements

preheat/interpass temperature

force/pressure humidity

Welding Welding process process controlcontrol

Welding current measurement

Definition: the current delivered by a welding power source during welding

measured with an ammeter measured in A the ammeter may be connected at any point in the

circuit indirect measurement: tachogenerator and

tongue tester

The tongue testerused for AC currentspecial types can be used also for DC

no need to insert the meter into the circuit

Arc voltage measurement

Definition: the potential difference across the welding arc

varies with the arc length measured with a voltmeter measured in V the voltmeter may be connected only across the

circuit (to the workpiece and as close as possible to the electrode!)

if the voltmeter is connected at the welding power source, a higher voltage will be recorded (due to potential drops across cables)

Travel speed measurementDefinition: the rate of weld progression measured in case of mechanised and

automatic welding processes in case of MMA can be determined using

ROL and arc time

2Gas flow rate measurementDefinition: the rate at which gas is caused to flow

set with a gas regulator

can be checked with a flowmeter

Welding temperatures-definitionsPreheat

temperature is the temperature of the workpiece in the

weld zone immediately before any welding operation (including tack welding!)

normally expressed as a minimum

Interpass temperature

is the temperature in a multirun weld and adjacent parent metal immediately prior to the application of the next run

normally expressed as a maximum

Preheat maintenance temperature

is the minimum temperature in the weld zone which shall be maintained if welding is interrupted

shall be monitored during interruption

Minimum interpass temperature = Preheat temperatureMinimum interpass temperature = Preheat temperature

Welding temperatures-WHERE?

Point of measurement - see BS EN ISO 13916

if t 50 mm A = 4 x t but max. 50 mm

the temperature shall be measured on the surface of the workpiece facing the welder

Welding temperatures-WHERE?

Point of measurement - see BS EN ISO 13916

if t > 50 mm A = min. 75 mm where practicable, the

temperature shall be measured on the face opposite to that being heated

allow 2 min per every 25 mm of parent metal thickness for temperature equalisation

interpass temperature shall be measured on the weld metal or immediately adjacent parent metal

Welding temperatures-HOW?

Test equipment

Temperature Temperature sensitive sensitive materials materials

Contact Contact thermometer thermometer

ThermocoupleThermocouple

Optical/electrical Optical/electrical devices for devices for contactless contactless

measurement measurement

Thermistor Thermistor

Temperature test equipmentTemperature sensitive materials:

crayons, paints and pills

cheap

convenient, easy to usedoesnt measure the actual temperature!

3Temperature test equipmentContact thermometer

use bimetallic strips accurate

easy to use

gives the actual temperature

need calibration

suitable for moderate temperatures

Temperature test equipment

Thermocouple

accurate methodmeasures over a wide range of temperaturesgives the actual temperatureneed calibration


Thermistorsare temperature-sensitive resistors whose resistance varies inversely with temperature

used when high sensitivity is required

gives the actual temperature

need calibration

can be used up to 320C


Devices for contactless measurementIR radiation and optical pyrometermeasure the radiant energy emitted by the hot bodycontactless method can be used for remote measurements very complexfor measuring high temperatures

PAMS (Portable Arc Monitor System)

The purposes The purposes of a PAMSof a PAMS

For calibrating For calibrating and validating and validating

the welding the welding equipmentequipment

For measuring For measuring and recording and recording

the welding the welding parametersparameters

PAMS (Portable Arc Monitor System)

What does a PAMS measure?Welding Welding current (Hall current (Hall effect effect device)device)

Arc voltage Arc voltage (connection (connection leads)leads)

Temperature Temperature (thermocouple)(thermocouple)

Wire feed Wire feed speed speed (tachometer)(tachometer)

Gas flow Gas flow rate rate (heating (heating element element sensor)sensor)

4Calibration, validation and monitoring

Definitions: Measurement = set of operations for determining a value of a

quantity Repeatability = closeness between successive measuring

results of the same instrument carried out under the same conditions

Accuracy class = class of measuring instruments that are intended to keep the errors within specified limits

Calibration = checking the errors in a meter or measuring device Validation = checking the control knobs and switches provide

the same level of accuracy when returned to a pre-determined point

Monitoring = checking the welding parameters (and other items) are in accordance with the procedure or specification

Calibration and validation

When it is required?

once a year unless otherwise specified whenever there are indications that the

instrument does not register properly whenever the equipment has been damaged,

misused or subject to severe stress whenever the equipment has been rebuild or

repaired

See BS EN ISO 17662 for details!


When it is NOT required? when verification of the process is not required in case of small series and single piece production

when all the following conditions are fulfilled:- procedures are approved by procedure testing- production is carried out by the same welding machine used during procedure testing


When it is NOT required? in case of mass production when all the following

conditions are fulfilled:- production is controlled by pre-production testing, followed by testing of samples from production at regular intervals- a statistical quality control system is used- the process is stable between testing of samples- pre-production testing and sampling are performed separately for each production line (robotic cells)

Welding parameter calibration/validation

Which parameters need calibration/validation?

depends on the welding process see BS EN ISO 17662 and BS 7570 for details

How accurate? depends on the application welding current - 2,5% arc voltage - 5% wire feed speed - 2,5% gas flow rate - 20% (25% for backing gas flow

rate) temperature (thermocouple) - 5%

Example 1 - MMA elementary monitoring

IN THEORY any M.M.A. operation could require monitoring of:

welding current arc voltage R.O.L. preheat/interpass temperature electrode treatment and storage

IN PRACTICE (depending on the application) only the welding current could require monitoring with a tongue test ammeter

5Example 2 - High integrity MMA operation

IN THEORY, this might require monitoring of all the activities previously mentioned.

all of the above equipment would require calibration; any meters fitted to the power source or electrode ovens would also require calibration.

the equipment thus required would be: ammeter voltmeter stop watch tape measure thermometer calculator

OR a PAMS

Example 3 - MIG/MAG welding with a robot

IN THEORY, the following would require monitoring: wire feed speed amperage voltage travel speed gas flow rate repeatability of the controls

IN PRACTICE, a data logger would be preferred to monitor all the parameters; also a PAMS would be required to check the repeatability of the control knobs.

Summary

a welding power source can only be calibrated if it has meters fitted

the inspector should check for calibration stickers, dates etc.

a welding power source without meters can only be validated that the control knobs provide repeatability

the main role is to carryout in process monitoring to ensure that the welding requirements are met during production

Typical examination question 1

The measurement of welding parameters is common in arc welding practice. Comment on the parameters that can be measured and recorded,including the different types of equipment that maybe used.

This question by definition is related to monitoring Introduction: would include monitoring is dependent on the

integrity of the product. Welding parameters: need to be identified. (with

comments!) Equipment details: can be established from the welding

parameters identified. Conclusion: should incorporate calibration/validation and

the need for checking temperatures (interpass/preheat).

Typical examination question 2

This question is related more to the whole fabrication process: e.g.

QA/QC requirements Training, experience and qualification of welders and

inspectors Inspection procedures (during welding) Auditing to ensure that the above is taking place Calibration/validation and in process monitoring

Describe how you would ensure that the welding parameters listed in a WPS are being adhered to during production welding. Give the advantages and limitations of the methods used.

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Section 2 Approval testing, codes of practice

and application standards

Rev 3 August 2010 Approval Testing


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2 Approval Testing BS EN ISO 15607:2003 General rules. BS EN ISO 15609-1:2004 Specification and approval of welding procedure specification for arc welding. This standard lists all the information that is required to be recorded to describe the welding process. Part 1 deals with arc welding but other parts exist that deal with laser and electron beam welding for example. BS EN ISO 15614-1:2004+A1:2008 Specification and qualification of welding procedures for metallic materials, Welding procedure test, Part 1: Arc and gas welding of steels and arc welding of nickel and nickel alloys. This standard covers the conditions for the execution of welding procedure tests and the range of qualification for welding procedures for all practical welding operations within a defined range of variables. Although standards tests are defined, it is recognised that other application standards may also require additional testing. Where the production/joint geometry requirements do not represent the standardised test pieces as shown in this standard, the use of EN ISO 15613 shall be required (see below). Standard test pieces covered by this standard include: Butt joints in plate Butt joints in pipe T joint Branch connection A test made to meet the requirement of this standard shall be witnessed by an examiner or an examining body and once qualified does not expire with time. Because this standard confers a range of approval based on material thickness, material type and certain process variables, etc, individual welding procedure specifications detailing parameters to be used prepared in accordance with BS EN ISO 15609 can be used to give specific instruction to welders on the shop floor. Part 1 specifically refers to steel and nickel alloys as defined by metallic groupings in PD CEN ISO/TR 15608:2005. This standard also exists in many other parts that relate to other material groupings such as aluminium alloys (part 2), cast irons (part 3) copper alloys (part 6), other processes such as laser welding (part 13) and other situations such as overlay welding (part 7).



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BS EN ISO 15610:2003: Qualification based on tested consumables Approval by use of an approved welding consumable has been used for many years by some branches of industry. Approval of the welding consumables is carried out according to national schemes pending the establishment of European certification schemes. BS EN ISO 15611:2003: Previous experience Approval by reference to previous welding experience has a number of applications. Only welding procedures known from experience to be reliable should be used in such cases. BS EN ISO 15612:2004: Standard weld procedure Approval by reference to a standard welding procedure is presently used to a rather limited extent, but it is covered by a few national rules. This type of approval is attractive because it has the potential of lowering the costs related to approval testing for the individual manufacturer. BS EN ISO 15613:2004: Pre-production weld tests Approval by pre-production welding test is rarely mentioned in national standards. It is however, needed for special welding procedures and perhaps for specific applications, not covered by EN 15614-1:2004+A1:2008/15614-2:2005 Approval by a pre-production test is the only reliable method of approval for some welding procedures, of which the resulting properties of the weld strongly depend on certain conditions such as component, special restraint conditions, heat sinks etc, which cannot be reproduced by standardised test pieces. General details regarding testing etc in this standard are covered specifically by the requirements of BS EN ISO 15614 where appropriate.

2.1 Welder approvals - BS EN 287 BS EN ISO 287-1:2004 Approval testing of welders, Fusion welding: steels. This standard gives the requirements for qualification testing of welders for steels. Like BS EN ISO 15614, in order to avoid all variants of welding procedures used on the shop floor to be tested, the standard confers a range of approval based on necessary skills to produce a weld. The range of approval can be limited by material type, thickness, number of passes, joint type and welding position, etc. The extent of testing is less than for procedure qualification as it is assumed that the company will already have hold a valid procedure qualification test. The other main difference between procedure and welder qualification is that the qualification will expire with time. Prolongation can occur in six monthly intervals after which the welder shall require specific evidence that his work has been tested or shall re-test. Although not mentioned in the standard, where a large number of are required to be qualified with differing ranges of approval and differing expiry



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dates, this probably best managed by holding a register of qualified welders showing ranges of qualification or renewal dates, etc. Nowadays this can also be managed by proprietary software packages. The standard also gives guidance on the recommended job knowledge that a welder should be assessed against in order to carry out his duties. This is not mandatory at the present time. It should be noted that the standard only covers manual or partly mechanised processes. For qualification of automatic welding systems, BS EN 1418 should be used. It should also be noted that some standards such as BS EN ISO 15614 -1 do not refer to this standard but to ISO 9606-1. This is the standard that will replace BS EN 287, but as yet has not been formally issued. BS EN ISO 9606-2:2004 Approval testing of welders - Fusion welding: aluminium and its alloys. This standard gives guidance on welder qualification in aluminium alloys and is part of a family of standards that cover other material groupings such as copper (part 3) and titanium (part 5) BS EN 1418:1998 Welding personnel, approval testing of welding operators for fusion welding and resistance weld setters for fully mechanized and automatic welding of metallic materials. It is often assumed that robotic welding is a push button operation and does not require qualification. This standard requires that the operator carries out a witnessed test and that their functional knowledge shall be assessed against requirements contained in an annex. In this case range of approval is only limited by the welding unit and process. The approval period is similar to BS EN 287. Currently under review are: BS 4872 Part 1: Steels Approval testing of welders when procedure approval is not required. BS 4872 Part 2 Approval testing of welders when procedure approval is not required. Part 2: MIG and TIG welding of aluminium and its alloys. Note: BS 4872 may be withdrawn in the future when other EN equivalent standards are implemented.

2.2 Training There must be a system for identifying training needs and approval requirements for all welding operations.



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Documentation must include a record of each welder's training programme together with details of approvals gained or due for renewal. There should also be data on a welder's performance so that trends win defect occurrence can be noted and corrective training provided.

2.3 Definitions BS EN ISO 15607:2003 gives the definitions of all terms used in the completion of welding procedures and welder approval. Amongst these are: Welding procedure Specified course of action to be followed in making a weld, including the welding process(es), reference to materials, welding consumables, preparation, preheating (if necessary), method and control of welding and postweld heat treatment (if relevant), and necessary equipment to be used. Welding process For the welding processes, the nomenclature and definitions given in ISO 857-1 are followed in this standard. The numbering system for welding processes in EN ISO 4063 is also followed. Preliminary welding procedure specification (pWPS) A document containing the required variables of the welding procedure which has to be qualified has to be qualified sing one of the methods described. Welding procedure specification (WPS) A document that has been qualified by one of the methods described in clause 6 and provides the required variables of the welding procedure to ensure repeatability during production welding. Work instruction Simplified specification of the welding procedure, suitable for direct application in the workshop. Welding procedure qualification record (WPQR) Record comprising all necessary data needed for qualification of a preliminary welding procedure specification. Welding procedure test Making and testing of a standardized test piece, as indicated in the pWPS, in order to qualify a welding procedure. Pre-production welding test Welding test having the same function as a welding procedure test, but based on a non-standard test piece, representative of the production conditions.



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Standard welding procedure specification Welding procedure specification which has been qualified by a welding procedure test not related to the manufacturer and qualified by an examiner or examining body Note: A standard welding procedure may then be made available to any manufacturer. Previous welding experience When it can be shown by authenticated test data that the manufacturer's established production welding procedures have been capable of consistently producing welds of acceptable quality over a period of time. Tested welding consumable Welding consumable or consumable combination tested according to appropriate standards for testing of welding consumables. Welding consumable Materials consumed in the making of a weld, including filler metals and auxiliary materials. Essential variable Welding condition that requires qualification. Non essential variable Welding condition addressed in the WPS but not requiring qualification. Range of qualification Extent of qualification for an essential welding variable. Homogeneous joint Welded joint in which the weld metal and parent material have no significant differences in mechanical properties and/or chemical composition. Note: A welded joint made of similar parent materials without filler metal is considered homogeneous. Heterogeneous joint Welded joint in which the weld metal and parent material have significant differences in mechanical properties and/or chemical composition. Dissimilar material joint Welded joint in which the parent materials have significant differences in mechanical properties and/or chemical composition. Welding co-ordination personnel Personnel who have responsibilities in the manufacturing operation for welding and welding related activities whose competence and knowledge



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has been demonstrated by eg training, education and/or relevant manufacturing experience.

2.4 Codes of Practice and Application Standards

A welding approval test standard contains the minimum qualification requirements. For any particular product or application a code of practice or application standard may impose additional requirements or limitations, eg an all weld tensile test(s) is additionally required in PD 5500 which is not specified by BS EN 15607-15614 (formerly 288). The standards do not necessarily constitute good engineering practice and when using the approval standards this must be borne in mind.

2.5 Other welding approval standards: ASME IX An American standard welding used throughout the world, particularly in the petrochemical industries for pressure vessel, piping and storage tanks but also nuclear applications. AWS D1.1 Another American Standard specifically aimed at structural applications in carbon manganese and high strength steels. This standard allows the use of pre-qualified welding procedures, which is not common in the UK.



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2.6 Questions on approval testing and quality control

1 Sketch the following:

Butt weld in the PA position Butt weld in the PF position Fillet weld in the PC position

2 Name the abbreviations for:

Overhead butt weld in plate Overhead fillet weld in plate

3 Which weld position(s) would be required to give all-position approval in pipe?

4 To ensure that approval documentation meets the requirements of a standard, there are a number of areas which must be assessed.

Provide a checklist of the key areas that require such an assessment.

5 A welded test piece has been visually inspected and defects outside of the acceptance levels have been reported. What would be the most likely course of action you would take?



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2.7 Practical on Procedure and Welder Qualification Testing Case study 1 It is a requirement to approve both procedures and welders for the following: Production requirements Materials Low carbon and 316 stainless steel (not dissimilar joints) Thickness range: 5-30mm Joint types Butt weld with/without backing plate Welding positions All positions except vertical down Process 111 Consumables Basic electrodes Decide on appropriate tests to fulfil the above requirement: a To BS EN 15607-15614 and 287 b What are the implications with reference to range of approval? Case study 2: practical exercise Write up the pWPS, WPS, WPAR and WQR documentation requirements for the previous test piece which has been identified from Case Study 1.



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2.8 Questions on welding procedure and welder approvals 1 Describe what is meant by a welding procedure specification. How does this

differ from, but relate to, a welding procedure approval record?

2 A number of components are to be cut from a plate over a period of time for approval testing. How would you ensure that traceability of the materials is maintained?

3 A pipe welded welder approval test piece has been found to be non-identifiable. What steps must be taken before the weld may be allowed into production welding?

4 List all the essential variables that would be found on a WPS.

5 Give typical examples of the range of approval for the essential variables specified in 4 using the abbreviations specified in BS EN 15607-15614 and 287.



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2.9 Practical exercise on codes of practice and application standards

By now you should have a fair understanding of the requirements for procedure/welding approval. So see how well you can complete the following exercises: Exercise: A welder successfully completed the following test weld to BS EN 287 Part 1. Fill in the welder approval certificate (including the appropriate test results). Manufacturers name: JBEL Welder's name and identification: Joe Bloggs No. 007 Material specification: Low carbon steel Material form: Pipe Material dimension: 80mm diameter, 8mm wall thickness Joint type: Single vee but welded from one side Welding process: Manual metal arc welding Consumables: 3.2mm diameter. Basic coated electrodes to BS EN 499 - E5152NiB Welding parameters: 100-200 amps. 22-24 arc volts. Test position: HLO45



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FAA1 Questions: BS EN 287 By using EN 287 Part 1 complete the following: 1 If a client requires 'all position' approval in pipe, what test position is necessary? 2 With reference to range of approval, what does 'thickness' refer to on: a) A butt joint b) A fillet weld 3 If a butt welded test piece is completed in 6.0mm, what is the approval range? 4 If a welder completes a test in pipe is he covered to weld plate? 5 List the mechanical tests required for a butt weld in pipe. 6 Give three (3) reasons for re-approval of a welder. 7 What are the requirements for retesting of welders? 8 What is the extent of approval, with reference to joint types, if the test piece is a

single vee butt welded from one side? 9 In MMA welding what other types of electrodes are approved if a basic is used on

the test? 10 What is the period of validity of initial welder approval tests?

1WELDING PROCEDURE QUALIFICATION

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What is a What is a ProcedureProcedure?? A specified way to carry out an activity or a A specified way to carry out an activity or a process (see BS EN ISO 9000)process (see BS EN ISO 9000)

What is a What is a Welding procedureWelding procedure ??

Specified course of action to be followed in making a weld, including the welding process(es), reference to materials, welding consumables, preparation, preheating, method and control of welding and PWHT and necessary equipment to be used (see BS EN ISO 15607)

WELDING PROCEDURES

Most procedures are qualified, but not all?Most procedures are qualified, but not all?

A qualified welding procedure is one that has been tested to ensA qualified welding procedure is one that has been tested to ensure ure that the procedure is carried out to produce a weld that satisfithat the procedure is carried out to produce a weld that satisfies a es a minimum level of quality for the mechanical, physical or chemicaminimum level of quality for the mechanical, physical or chemical l properties desired.properties desired.

If these are not required, then If these are not required, then procedure qualification is procedure qualification is unnecessaryunnecessary

Do all welding procedures need to be qualified?Do all welding procedures need to be qualified?

Most production welding procedure are formatted on written documents or computer spreadsheets, but they need not to be written and may be a product of experience

Do all welding procedures need to be written?Do all welding procedures need to be written?

Procedure qualification-YES or NOProcedure qualificationProcedure qualification--YES or NOYES or NOA A Welding Procedure Specification (WPS)Welding Procedure Specification (WPS) is a is a document that has been qualified and provides document that has been qualified and provides the required variables of the welding procedure to the required variables of the welding procedure to ensure repeatability during production welding ensure repeatability during production welding (recommended form (recommended form -- see ASME Code, Section see ASME Code, Section IX, QWIX, QW--482 and BS EN ISO 15609)482 and BS EN ISO 15609)

To evaluate a To evaluate a Provisional Welding Procedure Provisional Welding Procedure Specification (pWPS)Specification (pWPS) we need to check if all the we need to check if all the parameters set will work together to produce the parameters set will work together to produce the desired resultsdesired results

What is a welding procedureWhat is a welding procedureWhat is a welding procedure

WPS

It is the main document used in welding activitiesIt contains information about:It contains information about:

welding processparent/filler material(s)joint preparationwelding positionpreheat/interpass temperaturePWHTwelding parameterssupplementary informations

Purpose of a WPS

to give information to the welder, inspector to achieve specific properties: mechanical

strength, corrosion resistance, etc to ensure freedom from defects to enforce quality assurance procedures to standardize on methods and costs to control production schedules to form a record to ease the application of a standard or contract

requirement give confidence to a product

2Types of WPS

BS EN ISO 15609

Part 1Part 1ArcArc

weldingwelding

Part 2Part 2GasGas

weldingwelding

Part 3Part 3ElectronElectron

beambeamweldingwelding

Part 4Part 4LASERLASERbeambeam

weldingwelding

Part 5Part 5ResistanceResistance

weldingwelding

Welding procedure qualification terms

Definitions (see BS EN ISO 15607):

Essential variable - welding condition that requires qualificationSupplementary essential variable - variable which influences the toughness of the weld joint (only in ASME Code, Section IX - see QW-401.3!) Non essential variable - welding condition addressed in the WPS but NOT requiring qualificationRange of qualification - extent of qualification for an essential variableExamining body - organisation who verifies compliance with the applicable standard

Range of qualification

Is the extent of qualification for an essential welding variable

Also known as extent of approval, range of approval or scope of approval

Provides a working range for each welding procedure approval or welder approval

Outside the range of qualification reOutside the range of qualification re--qualification is qualification is MANDATORY!MANDATORY!

a) Material thickness and pipe diameter (depending on the type of joint!)

b) Welding process

c) Welding position, amperage range, current type or number of runs

d) Parent material groups

e) Filler material type and size

f) Preheat/interpass temperature

g) PWHT type and parameters

h) Heat input range (kJ/mm)

Examples of Examples of Range of qualificationRange of qualification include:include:

Range of qualificationRange of qualification

Welding process designation

111 - MMA 114 - FCAW - no gas shield 121 - SAW single wire 122 - SAW - strip 131 - MIG 135 - MAG 136 - FCAW - active gas 137 - FCAW - inert gas 141 - TIG 15 - Plasma arc 311 - Oxy-acetylene welding

Designation acc. EN ISO 4063:Designation acc. EN ISO 4063:

Parent material grouping system

ISO 15608

SteelsSteels

Al andAl andAlAl

alloysalloys

Ni andNi andNiNi

alloysalloys

Ti andTi andTiTi

alloysalloys

CastCastironsirons

Cu andCu andCuCu

alloysalloys

Zr andZr andZrZr

alloysalloys

3Grouping system for steels

Group 1 C-Mn steels Group 2 Fine grain/TMCP steels Group 3 QT steels (except stainless) Group 4 Low Vanadium Cr-Mo steels Group 5 Vanadium free Cr-Mo steels Group 6 High Vanadium Cr-Mo steels Group 7 Ferritic, martensitic and stainless steels Group 8 Austenitic stainless steels Group 9 Ni alloy steels Group 10 Duplex stainless steels Group 11 HSLA steels

Welding position designationButt welds in plate (see ISO 6947)

Flat - PA Overhead - PE

Vertical up - PF

Vertical down - PG

Horizontal - PC

Welding position designationButt welds in pipe (see ISO 6947)

Flat - PAaxis: horizontal pipe: rotated

H-L045axis: inclined at 45pipe: fixed

Horizontal - PCaxis: vertical pipe: fixed

Vertical up - PFaxis: horizontal pipe: fixed

Vertical down - PGaxis: horizontal pipe: fixed

J-L045axis: inclined at 45pipe: fixed

Welding position designation

Fillet welds on plate (see ISO 6947)

Flat - PA Overhead - PD

Vertical up - PF Vertical down - PG

Horizontal - PB

Welding position designationFillet welds on pipe (see ISO 6947)

Flat - PA axis: inclined at 45 pipe: rotated

Overhead - PD axis: vertical pipe: fixed

Vertical up - PF axis: horizontal pipe: fixed

Vertical down - PG axis: horizontal pipe: fixed

Horizontal - PB axis: vertical pipe: fixed

Horizontal - PB axis: horizontal pipe: rotated

Welding position ranges-ISO 6947

4WPQRWPQRWPQRIt is the document that supports WPS

It contain all the information needed to qualify a pWPS:welding processparent and filler material(s)welder identificationjoint preparation for test piecewelding positionpreheat/interpass temperaturePWHTwelding parametersNDE and mechanical tests resultsrange of approval

WPQR form (see also ASME IX, QW-483)WPQR form (see also ASME IX, QW-483)

Welding procedure qualification

Standards used for procedure qualification:

BS EN ISO 15607 - Specification and qualification of welding procedures for metallic materials - General rules

A.S.M.E. Boiler and pressure vessel code Section IX -Qualification standard for welding and brazing procedures, welders, brazers and welding and brazing operators

Methods of qualification

BS EN ISO15607

BS EN ISO 15610Tested welding consumable

BS EN ISO 15611Previous welding experience

BS EN ISO 15612Standard welding procedure

BS EN ISO 15613Pre-production welding test

BS EN ISO 15614Welding procedure test

BS EN ISO 15614 contentBS EN ISO 15614 Specification and qualification of

welding procedures for metallic materials Welding procedure test; material related parts:

Part 1: Arc and gas welding of steels/arc welding of Ni and Ni alloys

Part 2: Arc welding of Al and Al alloys

Part 3: Arc welding of cast irons

Part 4: Finishing welding of Al castings

Part 5: Arc welding of Ti, Zr and their alloys

Part 6: Welding of Cu and Cu alloys

BS EN ISO 15614 contentBS EN ISO 15614 Specification and qualification of

welding procedures for metallic materials Welding procedure test; application related parts:

Part 7: Overlay weldingPart 8: Welding of tubes to tube-plate jointsPart 9: Underwater hyperbaric wet weldingPart 10: Hyperbaric dry weldingPart 11: Electron and LASER beam weldingPart 12: Spot, seam and projection weldingPart 13: Resistance butt and flash welding

BS EN 288 Part 9 Pipeline welding (on land & offshore)BS EN 288 Part 9 Pipeline welding (on land & offshore)

5BS EN ISO 15614-1 provisions

Type of test pieces

Butt joint in plate

Butt joint in pipe

T joint (fillet or bevel) Branch connection

BS EN ISO 15614-1 provisions

Required tests (butt joint)

visual (EN 970)visual (EN 970)radiographic (EN 1435) or radiographic (EN 1435) or ultrasonic (EN 1714 ultrasonic (EN 1714 -- not to be used not to be used for t < 8mm!)for t < 8mm!)dye penetrant (EN 571dye penetrant (EN 571--1) or 1) or magnetic particle (EN 1290)magnetic particle (EN 1290)

NDTNDT Destructive testsDestructive tests

transverse tensile (EN 895) transverse tensile (EN 895) -- 2 2 specimensspecimenstransverse bend (EN 910) transverse bend (EN 910) -- 4 4 specimensspecimensimpact (EN 875) impact (EN 875) -- 2 sets2 setsmacroscopic (EN 1321) macroscopic (EN 1321) -- 1 1 specimenspecimenhardness (EN 1043hardness (EN 1043--1)1)


Required tests (fillet joint)

visual (EN 970)dye penetrant (EN 571-1) or magnetic particle (EN 1290)radiographic (EN 1435) or ultrasonic (EN 1714) for full penetration T and branch welds only!

NDTNDT Destructive testsDestructive tests

macroscopic (EN 1321) - 2 specimenshardness (EN 1043-1)if mechanical properties are relevant to the application, an additional butt weld qualification is required!


Acceptance standards

BS EN 25817 level BBS EN 25817 level C for excess weld metal, excess convexity, excess throat thickness and excessive penetration

NDT + MacroNDT + Macro Destructive testsDestructive teststensile test min. UTS of parent metalbend test no flaw > 3 mm in any directionimpact test avg. value per set = min. for parent metal at test temperaturehardness test - see Table 2 (non HT vs. PWHT!)


Re-test

Failed NDTFailed NDT Failed testsFailed tests

Weld one new Weld one new test piecetest piece

Failed NDT on Failed NDT on new test piecenew test piece

Test 2 new specimens Test 2 new specimens for any failed test for any failed test

specimenspecimen

Failed new testsFailed new tests

REJECTREJECT


Range of qualification for manufacturer:validity restricted to workshops and sites under the same technical and quality controlsame technical and quality control = manufacturer who perform the procedure test retains complete responsibility for welding

material grouping according ISO 15608range of qualification - see Tables 3 and 4

Range of qualification for parent material:


Thickness definitions:butt parent metal thicknessfillet - THICKER material at jointT-butt - PREPARED plate thicknessset-on branch - BRANCH pipe thicknessset-in/through branch - MAIN pipe thickness

BranchBranch Main Main pipepipe


Range of qualification for thickness - butt welds (for fillet welds see Table 6):

*If impact requirements are specified:*If impact requirements are specified:

Range of qualification (mm)Range of qualification (mm)Thickness of the test Thickness of the test piece piece tt (mm)(mm)

t t 333 3 t t 1212

0,7t0,7t--1,3t1,3t0,5t0,5t--1,3t(min.3 mm)*1,3t(min.3 mm)*

Single runSingle run Multi runMulti run

12 12 t t 100100t t 100100

0,5t0,5t--1,1t1,1tN/AN/A

0,7t0,7t--2t2t3 mm3 mm--2t*2t*

0,5t0,5t--2t2t50 mm50 mm--2t2t

no impact test performed upper limit of qualification is 12 mmimpact test performed upper limit of qualification is 1,3t or 2t respectively


Diameter definitions:butt outside diameter of the pipebranch - outside diameter of the BRANCH pipe

Range of qualification for outside pipe diameterRange of qualification for outside pipe diameter

Outside diameter of the Outside diameter of the test piece test piece DD (mm)(mm)

Range of qualification Range of qualification (mm)(mm)

D D 2525D D 2525

0,5D0,5D--2D2D 0,5D (min. 25 mm)0,5D (min. 25 mm)

qualification on plates covers fixed pipes with OD > 500 mmqualification on plates covers rotated pipes in PA or PC position with OD > 150 mm


Range of qualification for welding process:approval valid only for process usedmulti-process procedures - valid for order usedduring approval testmulti-processes procedures processes may be qualified separately or in combination.each degree of mechanization (manual, mechanized or automatic) need to be qualified separatelyfor 121 (automatic, mechanized, etc) each variant need separate qualificationfor 135 qualification using dip transfer qualifies only dip transfer


Range of qualification for welding positions:

welding in any position qualifies for all positions except PG and J-L045 which requires a separate test.

in case of impact/hardness requirements, impact tests shall be taken from highest heat input position (i.e. PF) and hardness tests from the lowest heat input position (i.e. PC or PE) in order to qualify all positions


Range of qualification for type of joint/weld:

butt welds qualify full/partial penetration butt welds and fillet weldsbutt welds on pipe qualify also branch connections with angle over 60T joints only qualify T joints and filletfillet welds qualify only fillet welds (recommended if they are the predominant form of production welding!)cannot change multi-run to single run or vice versa


Range of qualification for type of weld/joint:

single side welds made without backing qualify double side welds and single side welds using backingsingle side welds made using backing qualify double side weldsfor 141 process, welds without backing gas qualify welds with backing gasdouble side welds made without gouging qualify for double side welds made with gouging


Range of qualification for filler material:the filler used during qualification covers other fillers with equivalent mechanical properties, same type of covering/flux, same composition and same or lower hydrogen contentif impact test is required, for processes 111, 114, 121, 136 and 137, qualification is valid ONLY to the specific make used during the testother makes can be used ONLY after supplementary impact test on weld metalchanges in size of the filler are allowed if heat input conditions are satisfied


Range of qualification for filler material:

for 141 and 311 processes, welding with filler doesnt qualify autogenuos welds and vice versa

qualification given to the shielding gas is restricted to the to the symbol of the gas (see BS EN 439)
