N-11038- Method Statement for Cleaning, Welding and Painting of Steel Angles & Casings-old

TENDER No: N-11038

REHABILITATION AND PROTECTION WORKS FOR 132 kV OHTL TOWER FOUNDATION AND CORRODED STEEL LEGS

METHOD STATEMENT FOR CLEANING, WELDING AND PAINTING OF STEEL ANGLES & CASINGS

METHOD STATEMENT FOR CLEANING, WELDING AND PAINTING OF STEEL

ANGLES & CASINGS

TENDER NO: N-11038

REHABILITATION AND PROTECTION WORKS FOR 132 kV OHTL TOWER FOUNDATION AND

CORRODED STEEL LEGS

CLIENT : TRANSCO

CONTRACTOR : KEC INTERNATIONAL LTD.

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1.0 Specific work Activity and Scope :

The purpose of this Method Statement is provide the methodology to carry out cleaning, welding and painting of steel angles and casings. It will be assured that the work is done in line with good engineering practices and is compliance with engineering standard practices , nation & local codes.

2.0 Terminology:

OHL : Over Head Transmission Line.

Welding : Manual metal arc welding: Danger:

Danger is a risk to Human health, Property and Environment damage.

Danger Notice:

A notice of an approved type conveys a warning of the Danger. These notices are also displayed at the limits of safe working areas, calling attention to the adjacent Dangers.The Text on Danger Board is as follows:

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DANGERSTOPOVER HEAD TRANSMISSION LINE WORKS UNDER PROGRESSGeneral Safety:

The provision and maintenance of safe access to and from the place of work, a safe place of work, a safe working environment, safe methods of work and the correct use of effective personal protective equipment.

Supervision:

The control and direction exercised by a Competent Person who is present at the point of work at all times during the progress of the work.

3.0 Roles and Responsibility : Project Manager :

Overall control and Project Management of all activities at Project level. Distribution of resources & finance. Review and implement procedure for meeting statutory and quality requirements. Co-ordination with project co-ordinators and customer / consultant / sub contractors / sub vendors / local statuary bodies at the Project level and shall have the final responsibility on HSE.

Site Engineer :

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For ensuring all the activities are undertaken and constructed as per the drawings, co- ordinate for necessary work permits, all approved QC requirements are met by the construction team and ensure that all necessary resources are available to meet the schedule targets.

Safety Officer : For ensuring all the activities are undertaken and constructed in a safe manner as per the TRANSCO’s approved Method Statement, Risk Assessment & HSE Manual.

Site Supervisor : For ensuring that all the works are executed meeting TRANSCO’s HSE & QC requirements, allotment and supervision works to individual groups, conduct Tool Box Talks, Guide and Monitor the work force for progress, report to the Site Engineer on regular basis.

4.0 Document requirement, Drawing, Safety Documents: -

• Technical specifications of materials used for cleaning, welding and painting.

• Material Safety Data Sheet (MSDS) documents of Paint.

• Product Data Sheet of Paint

5.0 Main Tools & Equipment Welding M/C, welding rod and Welding Tool kit

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http://www.sciencelab.com/msdsList.php

TENDER No: N-11038



Generator Paint and Painting tool kit

6.0 Step By Step Procedure for Steel angles 6.1 Survey

All the locations of OHL will be surveyed. Degree of corrosion across steel cross-section will

be estimated (whether less than 10% or greater than 10%)

Methodology of rectification will be classified depending upon the degree of corrosion found.

Preparation of design and required drawing for fabrication will be done and submitted for approval.6.2 Surface Preparation :

All steel plates shall be cleaned with potable water/ tool cleaner to remove all traces of dirt, zinc salt etc.

Clean the surface starting with a steel wire brush. Sand again with a finer grit sandpaper, and finish the sanding with a 240 grit sandpaper. Wipe with a damp rag to remove all traces of dust. Remove corrosive salts, chalks, marks, soil or other contaminants and foreign matter by brushing the steel with a stiff fibre or wire brush or a combination of both.

Ensure that all white zinc oxide and other surface contaminants are removed by abrading with abrasive paper. Remove all traces of wax, oil grease and other coating applied for protection by solvent cleaning, Berger Tool Cleaner.

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6.3 Methodology of painting if the steel cross section is reduced by less than 10% then following procedures of painting shall be carried out : -Application of Etch Primer Mix Luxaprime 1500, base : Hardener in the ratio of 4 : 1 by volume. You may add upto 5% thinner. Solvalux 5-30 for application. Apply one coat of Luxaprime 1500 by brush / roller to a dry film thickness of upto 8 microns. Please ensure that the 2nd coat of Primer, Epilux 160 is applied after one hour or maximum the same day of application of Luxaprime 1500. Do not apply after pot life expires ie after 4-5 hours of mixing of base: hardener.Application of Epoxy Primer Same day mix Epilux 160. Base : Hardener in the ratio of 3 : 1 by volume. Add always hardener to the base at the time of mixing and not otherwise. Add 10-15 % Solvalux 7-45 (Thinner) for application of mixed paint after induction time of 10-15 minutes of the mixed paint. Then apply by brush or roller to a dft of 50 microns.Application of First Coat FinishNext day, Mix Epilux 5 Black. Base: Hardener in the ratio of 3 : 1 by volume. Add always hardener to the base at the time of mixing and not otherwise. Add 10-15 % Solvalux 7-45 (Thinner) for application of mixed paint after induction time of 10 minutes of the mixed paint. Then apply by brush or roller to a dft of 125 microns

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Application of Second Coat FinishNext day, Mix Epilux 5 Black. Base: Hardener in the ratio of 3 : 1 by volume. Add always hardener to the base at the time of mixing and not otherwise. Add 10-15 % Solvalux 7-45 (Thinner) for application of mixed paint after induction time of 10 minutes of the mixed paint. Then apply by brush or roller to a dft of 125 microns.6.4 If the steel cross section is reduced by

more than 10% then design of tower shall be verified before carrying out manual metal arc welding 2 nos. of 8 mm steel plate stiffeners around damaged portions, with overlap length = 300mm+damaged length+600mm. shall be carried out. In case the damaged portion is in connection between concrete pile and stub angles, concrete shall be broken up to 300 mm until a healthy section is reached. Welding to be carried out as per the following procedures: -

6.4.1 Preparation for Welding It will be necessary to provide for temporary

alignment of the adjacent components which are to be welded together, and to hold them in position until they are welded. The methods adopted for alignment may have to be able to carry the weight of the components and in some cases a substantial load from the structure.

Safe means of access and a secure working platform must be provided for the welder and his

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equipment. The working platform may also have to incorporate weather protection, since wind, rain and cold can all adversely effect the quality of the weld.

The design of the weld and the preparation of the components to be joined must take into account the position of those components in the structure; the method statement for the erection and the welding procedure for each joint must take all these factors into account.

All the welding must be carried out by qualified welders in accordance with approved procedures.

A detailed welding plan must be made for the more important structural joints as well as for structures to which special specifications apply.

The earth return of the electric current must never be made through the steel frame of installations but must be directly connected to the construction part being welded.

The surface of the zone to be welded must be clean and dry.

6.4.2 Welding sequence

I. Consideration is to be given to the assembly sequence and the effect on the overall shrinkage of plate panels, assemblies, etc., resulting from the welding processes employed. Welding is to proceed systematically, with each welded joint being completed in the correct sequence, without undue interruption.

II. Where practicable, welding is to commence at the

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centre of a joint and proceed outwards, or at the centre of an assembly and progress outwards towards the perimeter so that each part has freedom to move in one or more directions.

III. Cooling/Post Weld Cleaning Post heat may be required to relieve internal stresses caused by the concentration of heat in the weld area. Post heating aids in slow down of the cooling process to minimize cracking. This is a good procedure to use when joining thick metals. Shielded metal arc and flux cored welding leaves a slag residue on the weld. Remove slag with a chipping hammer or by grinding.

After 6 hours of welding getting completed, same above mentioned procedures of painting shall be followed.

7.0 Cleaning of steel casings

Cleaning of steel casings shall be carried out for height = 200 mm from top level and following steps for surface cleaning and painting shall be carried out :-

7.1 Surface Preparation : Remove the loose laitance and glazing if any, by thorough wire brushing, rubbing stone and then clean

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the surface with Berger Tool Cleaner prior to application of 1st Coat as primer.7.2 Application of Primer Mix Epilux 5 Black. Base: Hardener in the ratio of 3 : 1 by volume. Add always hardener to the base at the time of mixing and not otherwise. Add 10-15 % Solvalux 7-45 (Thinner) for application of mixed paint after induction time of 10 minutes of the mixed paint. Then apply by brush or roller to a dft of 125 microns7.3 Application of Finish Next day, Mix Epilux 5 Black. Base: Hardener in the ratio of 3 : 1 by volume. Add always hardener to the base at the time of mixing and not otherwise. Add 10-15 % Solvalux 7-45 (Thinner) for application of mixed paint after induction time of 10 minutes of the mixed paint. Then apply by brush or roller to a dft of 125 microns.Above mentioned 2 coatings of coal tar epoxy paint have to be coated on foundation cap in total ( including approximately 50 cm of vertical surfaces of the foundation).8.0 Safety Precautions for Painting

Technicians and personnel engaged in painting shall wear proper coveralls, hand gloves, shoes & safety helmets.

Each person engaged in painting must wear dust mask and eye protector.

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Paints & chemicals shall be covered/sealed off sufficiently to prevent from spillage during transport from one tower location to another.

Environmental hazards shall be checked as follows:a) All paints & chemicals spilt shall be cleaned immediately. Ensure that there is always equipment and supply of absorbent materials readily available to absorb / breakdown or where possible, where encapsulate paint/chemical spillages.b) Control measures for storage of painting materials at site:Only approved containers / portable tanks shall be used for storage and handling. Approved metal safety cans shall be used for the handling and use of paints, etc.

Paints/chemicals shall not be stored in areas used for exits or normally used passage of people. Keep them in an appropriate and safe location such as away from sources of ignition.

Paints and chemicals shall be kept in closed containers when not actually in use. Cover the opening of the paint can with plastic wrap before closing the lid. This will help create an additional seal when the can is closed.

Store paint away from extreme heat and cold. Extremes in temperature will spoil paint and make it unusable. Keep away from freezing and hot temperatures in sheds. Hot temperatures near furnaces and direct sunlight can also affect the quality of leftover paint. Store in a cool, dry area.

Segregate used and unused paint containers at one side and mixing of paints with proper care.

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Solvents, chemicals & paint strippers utilized during cleaning should be disposed of properly after use as follows:

They shall not be dumped onto the ground, into storm sewers or seawater, or into sanitary sewer system.

All wastes shall be disposed of off site at an approved landfill site. It may be a separate waste disposal area which shall be designated on the construction site which contain clearly demarcated skips and bins.

Sufficient water and soap will be kept at each location for treatment in case of paint in contact with skin and eyes.

Work area will be declared as 'No Smoking Area'. Stand-by vehicle shall be at site at always to attend

any emergency. Provision of Fire extinguisher & First aid box in

stand-by vehicle at all times. All electrical equipment to be properly maintained

and earth protected and all conductive objects in the painting/spraying area shall be grounded as well.

Only qualified painter having enough experience and training in tower painting should be assigned.

Procedures to be followed in the event of Traffic Accident:

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A. If you are first to arrive on the scene of an accident:1. Inform Safety Department/ Call Operator – Dial

050-3982241 /02-6394886 by any communication means giving following information:

a)Nature of incidentb)Location of incidentc)Name and employment number

2. If safe to do so, turn off the engine of a crashed vehicle.

3.Make the area safe by putting safety cones, warning triangles etc.

4.Park your vehicle safely.5.Assist any injured.6.Wait for Emergency Team to arrive.

B. If you are involved in an accident:1. Inform Safety Department/ Call Operator - Dial

050/3982241, 02/6394886 by any communication means giving following information:

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a. Nature of incidentb.Location of incidentc. Name and employment number

2. Remain at the scene of any road accident until police give permission to go

3. Wait for Emergency Team to arriveNote: - Do not handle the casualty if you are not sure/qualified, to avoid further damage to the injured personnel.C. Off – Site Hazardous Emergency:-

Off site Hazardous emergencies may include the following: -1.Any off – Site fire likely to affect on – site

operations.2.Severe weather conditions are likely to affect on

site operations.3.Law enforcement emergency alert.

Employee must report any sighting of severe weather such as heavy winds, Rain flooding etc. immediately. Please identify the condition, approximate speed and direction of the weather patterns.

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On Site Equipment :- Pick up Truck Fire Fighting Equipment Emergency / First Aid Equipment Emergency Rescue Kit.

9.0 Safety precautions for WeldingFor protection from injury it is essential that the following safety precautions are followed:Use protective clothing and equipment (PPE)This includes:-

overalls or heavy drill cotton long trousers & long-sleeve shirt made from non-flammable material

safety footwear leather gauntlet gloves standards approved safety goggles with correct

filter lens shade wearing standards approved safety glasses when

working near flame cutting, gouging and heating operators

Note: Other safety issues relating to clothing; clothing worn by the operator should be in good

repair. Frayed clothing is a fire hazard leather clothing such as spats, aprons or leather

jackets may be necessary for some flame cutting, gouging and heating applications

lightweight clothing is not suitable for the intense heat emitted from flame cutting, gouging and heating operations

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Warning : Never leave butane cigarette lighters in your pockets whilst flame cutting, gouging and heating as this can result in an explosion causing serious injury or death.

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