piping drawing

8/12/2019 piping drawing

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CHECKING PIPING DRAWINGS PROCEDUREhttp://piping-info.blogspot.com

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DISCLAIMER

This Procedure is intent to prepare for the Piping Checkers perfection. Piping Infoaccepts noliability or responsibility whatsoever for it in respect of any use of or reliance upon this procedureby anyone or any entity.

1.0 PURPOSE

The purpose of this design procedure is to ensure accuracy and completeness of piping drawingsissued by the Mechanical Design Department; and identify responsibility, criteria, and specific itemsto be checked by the Mechanical Design Checker.

2.0 MECHANICAL DESIGN CHECKER RESPONSIBILITY

2.1 Responsible that the piping drawings are complete, accurate, interference free,constructible, maintainable, in compliance with System Design and Checking Guides,standards, standard deliverable drawings, project design criteria, vendor data, Processand Instrument Diagram (P&ID), project contract, and engineering requirements.

2.2 Responsible to verify the location and limits of drawing HOLDs to areas that areincomplete or can not be verified and approved by the checker prior to issue due toinsufficient engineering, vendor, client or other discipline information.

2.3 Responsible to verify that all reference data and documents used to perform the checkare the most current available. This includes vendor drawings, P&IDs, design criteria,thermal analysis, other discipline drawings and models. Use the Designed PipingSystem Folder that contains design information gathered by the Designer and LeadDesigner for each system.

2.4 Use a hard copy check print of the drawings for marking comments in red forcorrection that include additions, changes, or deletions. Graphics, dimensions, andnotes that are verified to be correct shall be highlighted in yellow. Comments, notes,references, etc that are not for correction shall be made in black graphite pencil.

2.5 Upon completion of the initial drawing check, the Checker shall return the check prints

to the originator or Lead Mechanical Designer for correction along with the DesignedPiping System Folder. After correction, the Checker is responsible to back check thedrawing to assure all corrections and engineering comments were incorporatedaccurately.

2.6 Responsible to check the complete content of the drawing and piping system designincluding but not limited to all items contained in this procedure. The checker shallcontact the Mechanical Lead Designer or Engineer for additional project specificrequirements.

2.7 Responsible to maintain check prints, records, and information until the piping system isfabricated, installed, and operating.


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3.0 DRAWING INFORMATION CHECK

3.1 Drawing Number. Check that the drawing number is in accordance with the projectnumbering system, client numbering system.

3.2 Drawing Revision Number/Letter and Description. Check that the drawing revisionnumber/letter is correct in the title block and revision description block according toproject revision numbering system. Check that the revision description in the revisionblock describes the purpose for the drawing issue or changes.

3.3 Drawing Title Block Information. Check that the text in the drawing title block is correctin accordance with the project standards Deliverable Drawings.

-Project Description- Drawing Type Description (Piping Isometric, Underground Piping Isometric, Small

Bore Piping Isometric, Analyzed Small Bore Piping, etc)- Piping System Description- Scale

3.4 Drawing Signatures. Check that drawing signatures are correct in the title block.

3.5 Back Circles. For revised drawings only, check that back circles are place aroundrevised areas to identify changes since the previous drawing issue. Check that backcircles from previous revisions have been removed.

3.6 Drawing Notes. Check that general and specific notes are in accordance with theexample on WorleyParsons Standard Deliverable Drawings and are applicable to thedrawing content and project specific requirements.

- Check drawing number references listed within the general notes.- Check Technical Specification number listed within the general notes.- Check Insulation Specification number listed within the general notes.

3.7 Drawing Attributes. Check that the line graphic and text attributes meet therequirements of the Project Cadd Specification.

3.8 Spelling and Abbreviations. Check the spelling of all text and abbreviations within thedrawing. Periods after abbreviations are not required.

3.9 North Arrow. Check that a north arrow is on the drawing, including at detail plan views.

3.10 Project Specific Requirements. Check with the Lead Designer and Project DesignCriteria for any project specific drawing or pipe system requirements.

4.0 PIPING SYSTEM INFORMATION CHECK

4.1 System to P&ID Check. Check that the pipe system matches the approved system P&IDincluding comments found on the projects Master Set of P&IDs. The checker is

responsible that the piping drawing and the P&ID are in agreement for the following:


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- Pipe Line Number

- Pipe Sizes- Pipe Line Specifications and locations of Line Spec changes within the pipeline.- Pipe Insulation Class- Branch and Component sequence- Equipment Tag Numbers and Descriptions- Component Tag Numbers- Flow direction- Heat Tracing limits, type, and thickness

4.2 Equipment Location, Description, Tag Number. Check the coordinate (n/s, e/w, andelevation) locations of all equipment to which the pipe system is connected in the model.The location shall match the general arrangement, equipment setting plan, and

civil/structural drawings. Check that the equipment description and tag number match theP&ID and Mechanical Equipment List.

4.3 Equipment Nozzle Location, Tag Number and Data. Check the equipment model nozzlelocation, size, connection end preparation, flange rating, pipe schedule are in accordancewith the latest equipment vendor drawing.- Check that nozzle information on piping drawing is correct- Butt Weld nozzles shall include the nozzle pipe schedule or wall thickness

4.4 Piping Connection to Equipment Nozzle. Check the pipe connecting to the equipmentnozzle matches the nozzle attributes and is compatible.- Flat Faced or Raised Faced Flanges

- Butt Weld Nozzles requires matching material and pipe wall thickness. Identify

dissimilar metal welds and wall thickness between nozzles and pipe.- Non-USA vendor may provide nozzles that do not comply with ASME B16.25 weld

bevel standards. Identify locations of any pipe joint that requires a bevel different thanthe ASME standard.

4.5 Flow Direction Arrow. Check that each pipe line contains one flow direction arrow. Eachsheet of a piping isometric shall contain a minimum of one flow direction arrow.

4.6 Completeness. Check that all dimensions, notes, information, and details that arerequired for the construction and installation of the piping are included.

- Compliance with System Design Guides. Check that the piping system is designed in

accordance with the Mechanical Design Department specific system design guides.

4.7 Project System Design Criteria Documents. Check that the piping system is designed incompliance with project/client design criteria documents.

4.8 Valve and In-Line Components. Check all valves and in-line pipe components (flowelements, expansions joints, orifice plates, restricting orifices, etc) end to end dimensionsand connection attributes from approved vendor drawings. Check that the connectionsize, type and schedule match the attributes of the pipe. Check all valve actuators for

correct size, orientation and that they are accessible for operation and maintenance.


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- Standard end to end dimensions per ASME/ANSI B16.10 for valves 600 lb class and

below may be approved without approved vendor drawings for gates, globe, andcheck valves. All other valves shall be on hold until approved vendor drawings areavailable.

- Butterfly, control, ball, plug, and relief valve end to end dimensions do not conform toend to end standards and shall be on hold until approved vendor drawings areavailable.

- Identify dissimilar metal welds and wall thickness between component and pipe.-- Check that chain wheel operators are provided on non accessible valves.

4.9 Valve, Flow Element, and In-Line Component Installation Requirements.

Check vendor drawings and installation instructions for installation requirements ofvalves, flow elements and in-line components within the pipeline.

- Straight pipe upstream and downstream requirements- Valve stem orientation (especially butterfly valves)- Clearances for valve maintenance and disassembly.- Lugged butterfly valves shall be noted on drawings for proper bolting procurement.- No gaskets required at low pressure butterfly valves and expansions joints.- Flat face flanges required at flanged expansion joints- Flat face flanges are required at cast iron equipment flanges- Flow element upstream and downstream straight pipe requirements according to the

Control System Engineer requirements.

4.10 Vents and Drains. Check quantity and location of vents and drains. Check that all ventand drain connections reference the correct standard detail number.

4.12 Minimum pipe spool lengths. Check that there are adequate pipe spool lengthsbetween pipe line components. Use the following as a guide. Large Bore Butt Weld:Minimum spool length equivalent to the length of a butt weld reducer. Small BoreSocket Weld: Minimum exposed pipe length between socket weld components endsshall be 2.

4.13 Separation Distances for Branches. Check that there is adequate separation distancebetween pipe branches and adequate separation distances between branches and

pipe line ends or components.

4.14 Instrument Connection Orientation and Access. Check that instrument connectionsthat require access are accessible and that the orientation on the pipe is correct.Check for proper connection type and size. Check that all Instrument connectionsreference the correct standard detail number, and there are sufficient clearances forelement removal from pipe.

- Temperature connections shall be located downstream of pressure connections.- Temperature thermowells cannot be installed in pipes smaller than 3.

4.15 Insulation and Insulation Support Lugs. Check insulation requirements to Project

insulation class codes and thickness. Add insulation support lugs on vertical runs ofalloy pipe.


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4.16 Heat Tracing. Check that piping is Heat Traced as identified on the system P&ID andin accordance with the Project Heat Tracing Criteria.

4.17 Pipe Penetrations symbols. Check that all concrete floor, platform grating, wall, andgrade penetrations are indicated and labeled on piping isometrics. Callout core drilledopenings in existing walls when required.

4.18 Waterstops. Check that water stops are provided on underground piping at floor andwall penetrations.

4.19 Slope. Check that pipe systems that require slope have the proper minimum slopeand the correct slope direction. For hot piping verify pipe does not reverse slope in hot

position.

4.20 Pipe Supports and Welded Attachments. Check that pipe supports are shown whenrequired and locations, quantity, and tag numbers have been review and approved bythe Piping Engineering department. Check that shop welded pipe support attachmentdetails are provided on alloy piping for shop welding before shop stress relieving.

4.21 Material List on Isometrics. Check that all pipe and pipe component materialdescriptions in the isometric drawing material list matches the engineering pipe linespecification.

4.22 Insulating Flange Kits. Check that insulating flange kits are identified on abovegroundpiping systems connecting to underground pipe systems where required by thepipeline specification.

4.23 Dissimilar Metal Welds. Check that dissimilar metal welds that may occur at valves,equipment nozzles, and material spec changes are identified and transition pieces areprovided if required.

4.24 Dissimilar pipe and/or component wall thickness. Check that dissimilar pipe andcomponent wall thicknesses that may occur at valves, equipment nozzles, and atmaterial spec changes are identified and transition pieces or taper bores are providedif required. ASME Power Piping Code B31.1 Section 127.3C allows a 1/16 (.0625)

internal pipe wall misalignment (each side) for welding without taper boring theconnecting pipe. Example of piping drawing identification of dissimilar wall thicknesstaper bore: TAPER BORE SCH 160 PIPE TO MATCH SCH 80 VALVE

5.0 PIPING SYSTEM ROUTING AND LAYOUT CHECK

5.1 Interference Check. Check that the system is interference free by a visual review of themodel and that a recent electronic interference report from the model had been reviewedand cleared. If a non 3D project, review all discipline reference drawings. If the piperouting is within an existing plant area, verify a field interference check was performed.For hot piping verify pipe clearances in hot positions.

5.2 Thermal Analysis. For hot piping verify WorleyParsons Piping Engineering Departmenthas approved the thermal flexibility of the pipe. Checker is responsible to obtain pipe


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thermal movements and verify clearances in hot position and that pipe does not reverse

slope causing low point pockets. Thermal movements direction and distance shall benoted on check prints in blue for future reference.

5.3 Hazardous Areas. Check that no electronic instrument, valve actuator, or other electroniccomponent within the pipe or attached to the pipe falls within a Hazardous Area of theplant.

5.4 Plant Personnel Access, Construction Access, Maintenance Areas, and Safety. Checkthat the pipe system layout does not obstruct plant personnel access, constructionaccess, and maintenance areas of the plant. Check that the pipe system lowestappendage (including pipe support clamps) is above 6-8 headroom and does not affectplant safety.

5.5 Pump and Equipment Requirements. Check that the pipe system layout meets therequirements of the connecting equipment vendor requirements or common practice.The checker shall read all vendor criteria. Examples:

- Pump suction straight diameters, eccentric reducers- Steam Turbine vendor requirements- Check pipe system against Equipment Vendor P&ID if applicable- Installation and Maintenance Manuals

5.6 System Discharge Points. Check that safety valve discharges, gas vents, etc aredischarged in a safe location that will not be harmful to personnel, structures, or

equipment. Confirm safety valve discharges do no impact noise abatement requirements.Confirm gas (fuel gas, hydrogen) discharge points are indicated on hazardous arealocation drawings.

5.7 Underground Pipe Burial Depth. Check that underground pipe has adequate cover toprotect from crushing from vehicle, railroad, and crane loads and is below frost depth.

5.8 Pipe Lanes. Check that pipe system layout is within established pipe north/south,east/west pipe lanes and elevations established within the plant. Underground piping shallhave common bottom of pipe elevations for trenching.

5.9 Structural Gusset Plates. Check that the pipe system does not interfere with areas to be

occupied by structural gusset plates. Not all gusset plates are in the model and thosethat are modeled may not represent the actual structural fabricators detail andrequirements. Checkers must do a visual model interference check at gusset plate areasand interface with structural design to assure sufficient clearances.

5.10 Circulating Water Branch Component Reinforcement Plate clearance. Check forpotential interferences in the area of large pipe component reinforcement plates,especially at crotch areas of laterals.

5.11 Underground Potable Water and Waste Water Separation. Check local and statecodes for separation requirements between underground potable water and wastewater systems to prevent pollution of potable water.


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5.12 HDPE Pipe Fitting Separation and Butterfly Valves. Check that there are pipe spools

between all HDPE pipe fittings to accommodate differences in physical dimensionsbetween HDPE fitting manufactures. Check that Butterfly Valves discs are notobstructed from opening when connected to heavy wall HDPE pipe. Pipe spacersmay be required between the flange and valve body.

5.13 Clearance from vertical structural columns and walls. Check that pipe routingmaintains approximately 9 inches of clearance from vertical structural columns and walls(including hot position) to allow space for field routed utilities.

5.14 Olet Branch Dimensions. Olet type pipe branch fittings (weldolet, sweepolet, etc)dimensions (run pipe centerline to the fitting outlet) are approximate because the

dimension varies by manufacture. Check that fitting to fitting design on the outlet ofthe olet branch fittings is not used. A pipe spool is required for adjustment by the pipefabricator to suit actual fitting dimensions while maintaining the overall geometry ofthe pipe system.

5.15 Miscellaneous Items for Checking List. Includes commonly found piping isometricIsogen software errors requiring manual annotation.

a) Orifice Flange pressure tap orientations incorrectly shown by Isogen.b) Dimensions or dimension strings starting at pipe caps. Isogen dimension is

from cap work point (center of cap where blue line stops) but dimensionson drawing appears to be from end of cap.

c) Eccentric Reducer offset dimensions incorrectly shown by Isogen do not

match actual fitting offsets as manufactured and should be deleted.

6.0 HOLDS CHECK

6.1 Holds. Check the location and limits of drawing HOLDs to areas of the drawing that areincomplete or can not be verified and approved by the checker prior to issue due toinsufficient engineering, vendor, client or other discipline information. See Section 2.2.

6.2 Hold List. Check that all drawing holds are included in the Holds List for the project.

7.0 PIPING DRAWING CHECK LIST

7.1 Check List. A summary of the items identified in this procedure is provided inATTACHMENT 1 Piping Drawing Check List.

This list may be printed and used as a checking tool or record at the discretion of theMechanical Design Checker.


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ATTACHMENT 1

PIPING DRAWING CHECK LIST

DRAWING INFORMATION CHECK

3.1 Drawing Number 3.2 Drawing Revision Number/Letter and Description 3.3 Drawing Title Block Information 3.4 Drawing Signatures 3.5 Back Circles 3.6 Drawing Notes 3.7 Drawing Attributes 3.8 Spelling and Abbreviations

3.9 North Arrow 3.10 Project Specific Requirements

PIPING SYSTEM INFORMATION CHECK

4.1 System to P&ID Check4.2 Equipment Location, Description, Tag Number4.3 Equipment Nozzle Location, Tag Number, and Data4.4 Piping Connection to Equipment Nozzle4.5 Flow Direction Arrow4.6 Completeness (All required dimensions, notes, information, details required for

construction)

4.7 Compliance with System Design Guides4.8 Project Design Criteria Documents4.9 Valve and In-Line Components4.10 Valve, Flow Element, and In-Line Components Installation Requirements4.11 Vents and Drains4.12 Minimum Pipe Spool Lengths4.13 Separation Distances for Branches4.14 Instrument Connection Orientation and Access4.15 Insulation and Insulation Support LugsHeat TracingPipe Penetration Symbols and/or callout of core drilled openingsWaterstops

SlopePipe Supports and Welded AttachmentsMaterial List on IsometricsInsulating Flange KitsDissimilar Metal WeldsDissimilar pipe and/or component wall thickness


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ATTACHMENT 1 (CONTINUED)PIPING DRAWING CHECKLIST

PIPING SYSTEM ROUTING AND LAYOUT CHECK

5.1 Interference Check5.2 Thermal Analysis5.3 Hazardous Areas5.4 Plant Personnel Access, Construction Access, Maintenance Areas, and Safety5.5 Pump and Equipment Requirements5.6 System Discharge Points5.7 Underground Pipe Burial Depth

5.8 Pipe Lanes5.9 Structural Gusset Plates5.10 Circulating Water Branch Component Reinforcement Plate clearance5.11 Underground Potable Water and Waste Water Separation5.12 HDPE Pipe Fitting Separation and Butterfly Valves5.13 Clearance from vertical structural columns and walls5.14 Olet Branch Dimensions5.15 Miscellaneous Items for Checking List

HOLDS CHECK

6.1 Holds

6.2 Holds list