h-231

PDVSA N° TITLE

REV. DATE DESCRIPTION PAG. REV. APPD. APPD.

APPD.BY DATEDATE

VOLUME 13–II

� PDVSA, 1983

H–231 PIPING FABRICATION REQUIREMENTS

ORIGINAL

A. Arévalo J. E RojasDEC.98 DEC.98

ENGINEERING SPECIFICATION

FEB.89

DEC.98 Y.K.

J.S.

1

0

GENERAL REVISION 17

13

A.A.

J.G.

J.E.R.

E.S.

ENGINEERING DESIGN MANUAL

ESPECIALISTAS

APPD.BY

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PIPING FABRICATION REQUIREMENTS DEC.981

PDVSA H–231

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.Menú Principal Indice manual Indice volumen Indice norma

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Index1 GENERAL 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.1 Scope 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Specifications, Codes and Standards 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Regulations 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 MATERIALS 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 Pipe and Fittings 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Bolting and Gaskets 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 FABRICATION 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 DRAWING 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 CUTTING AND BEVELING 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 Beveling 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 Flame Cutting 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 BENDING 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1 General 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 Miter Bends 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3 Elbows 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4 Branch Connections 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 FIT–UP JOINT 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1 Line Joints 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2 Tee and Lateral Joints 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3 Flanges 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 WELDING 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1 General 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2 Welding Process 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.3 Welding Electrodes 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4 Selection of Welding Electrodes 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 HEAT TREATMENTS 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.1 Weldments 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 Special Heat Treatments 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10 FINAL CORRECTIONS 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 TOLERANCES 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12 INSPECTION AND TESTS 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1 Inspection of Welds 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2 Hardness Test 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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12.3 Hydrostatic Pressure Test for Piping Sub–Assemblies 12. . . . . . . . . . . . . . . . 12.4 Dimensional Check 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13 SHIPMENT 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1 Preparation for Shipment 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.2 Spool Piece Marking 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1 GENERAL

1.1 Scope

1.1.1 This specification contains general, fabrication details, inspection and testingrequirements applicable to process and utility piping systems shop or fieldfabricated. Piping or pipeline out of the scope of ASME Code B31.3 is not coveredby this specification.

1.1.2 Fabrication under this specification includes all components of a piping system, orpart thereof, entering into fabricated assemblies, but shall exclude all valves,bolting, gaskets, flanged fittings, blind flanges, orifice plates, and all specialty items

1.2 Specifications, Codes and StandardsThe latest editions of following specifications, codes, standards and practices,including applicable addenda, shall form a part of this specification to the extentspecified herein:

1.2.1 Petróleos de Venezuela S.A. (PDVSA)

H–221 Piping MaterialsH–223 Pipeline and Pipe BendsO–201 Painting Materials and Application RequirementPI–02–05–04 Inspección de Soldaduras Circunsferenciales en Tuberías e

InstalacionesPI–02–08–01 Pruebas Hidrostáticas y Neumáticas para Sistemas de Tuberías

1.2.2 American Society of Mechanical Engineers (ASME)

Codes:

B31.1 Power PipingB31.3 Process PipingSection I Power BoilerSection II MaterialsSection VIII – Div 1 Pressure VesselsSection IX Welding QualificationsStandards

B1.20.1 Pipe Threads. General PurposeB16.25 But Welding Ends

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1.2.3 American Welding Society (AWS)

A5.1 Specification for Carbon Steel Covered Arc Welding Electrodes.A5.4 Specification for Corrosion – Resisting Chromium and Chromium

– Nickel Steel Covered Welding Electrodes.A5.5 Specification for Low Alloy Steel Covered Arc Welding Electrodes.

1.2.4 Pipe Fabrication Institute (PFI)

ES–24 Piping Bending Methods, Tolerances, Process and MaterialRequirements

1.3 RegulationsShould there be any conflict between Venezuelan laws, standards and regulations,this specification and ASME standards, the order of prevalences shall be asfollows:

1. Venezuelan laws, standards and regulations

2. This specification

3. ASME

2 MATERIALS

2.1 Pipe and FittingsThe material specification for each piping assembly will be indicated on theOwner’s Drawings and/or in PDVSA Engineering Specification H–221, “PipingMaterials”, which supersede this specification in case of conflict.

2.2 Bolting and Gaskets

2.2.1 Threads of bolts and studs shall be coated in the field with a suitable lubricant toprevent damaging.

2.2.2 All bolts shall extend fully thru their nuts. The use of washers or other packings asa filler for excessive flange bolt lengths is not acceptable.

2.2.3 All flanged joints shall be brought up flush so the entire flange face or groove bearsuniformly on gasket and then made up with uniform bolt tension.

2.2.4 In bolting joints with spiral wound gaskets, the gasket shall be compressed by anamount equal to about 25% of the original thickness.

2.2.5 The bolting procedure shall be checked by measuring the decrease of the spacebetween flanges during tensioning.

2.2.6 150 # steel to 125 # cast iron flanged joints are permitted provided “raised face” ofsteel flanges be machined to flat face and shall be made up carefully to preventbreaking of cast iron equipment flanges.

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3 FABRICATION3.1 For steam boilers, proper piping and external piping shall be identified accordingly.

3.2 The type of flanges, fittings, and connections shall be indicated on Owner’sdrawings and/or in the PDVSA Engineering Specification H–221, “PipingMaterials”.

3.3 Longitudinal or helical seams in adjoining lengths of welded pipe shall be staggeredand located to clear openings and external attachments.

4 DRAWING4.1 Owner’s representative reserves the right to check sub–assembly fabricator’s

detail drawings and sketches total or partially, prior to initiate fabrication, in orderto guarantee Owner’s requirements.

4.2 The Fabricator shall be responsible for detail drawings and sketches conformingwith the Owner’s requirements.

4.3 Piping shall be fabricated in accordance with drawings. Pre fabricated spool piecesshall be per isometric drawings.

4.4 Field weld symbol (FW) shall be indicated on drawings or isometrics for spoolswhere distances, separations or lengths are accurately known and no fieldadjustment is required. Otherwise, fit field weld (FFW) symbol shall be indicated.In this case, an extra length of 152 mm (6 inches) shall be provided for the straightpipe portion to be adjusted.No FW or FFW symbols indicate full welding.

4.5 Typical cases for FW and FFW for carbon steel pipes 4 inches and larger; and foralloy steel pipes 3 inches and larger are:

FW:– Straight piping requiring weld joints.– Spools just for truck transportation.– Spools to be installed close to or between “hard to access” existing piping.

FFW:– To connect with rotating or static equipment.– To connect with existing piping.

5 CUTTING AND BEVELING5.1 Beveling

5.1.1 Unless otherwise required by the piping material or welding (1) processes, weldingends shall be prepared per ASME B16.25, except that for wall thickness of 4,8 to19 mm, inclusive, the bevel angle may be reduced to not less than 30 degrees.

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5.1.2 Beveled ends may be cut, shaped and beveled for welding by machining, sawingor grinding, or flame beveling.

5.2 Flame Cutting

5.2.1 Flame cutting may be used for carbon steel material.

5.2.2 The edges to be welded must be uniform and smooth and must be free of all foreignmatter before welding. (The color change which remains on the flame cut edgeshall be considered as a harmless oxidation).

5.2.3 Flame cutting, arc cutting, or flux injection torch cutting of alloy steel will bepermitted for rough cutting only.

5.2.4 Air hardening alloys shall be preheated and slow cooled to avoid cracking.

5.2.5 The edges of alloy steels so cut must be finished by machining, grinding, orchipping.

5.2.6 Grinding of austenitic stainless steel shall be done with a non–carbonaceouswheel.

6 BENDING

6.1 General6.1.1 Piping bending shall be in accordance with PDVSA Engineering Specification

H–223, “Pipeline and Pipe Bends”.

6.2 Miter BendsMiter bends may be used for pipe 12 inches NPS and greater, provided:

a. Bends over 45º shall be, at least, three pieces (two cuts)

b. Mean bend radius (at piping centerline) shall be, at least, equal to nominalpipe size (inches)

c. Maximun miter angle shall be 22–1/2º for piping up to 13,8 barg (200 psig)design pressure, 15º for piping up to 27,6 barg (400 psig) design pressure and11–1/4º for piping with more than 27,6 barg (400 psig) design pressure (SeeFigure 2).

6.3 Elbows6.3.1 Elbows shall be long radius and buttwelding ends, unless otherwise approved by

Owner’s representative.

6.4 Branch Connections

6.4.1 Branch connections for steam, instrument air, vapors and gas lines shall be madeon the top of header

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6.4.2 Where possible and economical, connections for 2 inches NPS and greaterheaders shall be made up by welding tee, weldolets or sockolets. Otherwise,branch connections made up by welded nozzles may be used. In all cases,requirements of ASME Code 31.3 shall be accomplished.

6.4.3 Integrally reinforced branch connections for 4 inches NPS or greater headers arenot permitted if:

a. d/D ratio is greater than 0,8.

D = header nominal diameter; d = branch nominal diameter

b. Header thickness is less than schedule standard thickness for same pipe.

c. Header thickness is less than 19 mm (0,75 in), nominal pipe size exceeds36 inches and operating temperature is 426 °C (800 °F) or greater.

6.4.4 When branch and header nominal diameters are identical, branch shall bereinforced with an encircled plate (full header diameter), with a length of twicebranch diameter and same thickness of header, at least.

6.4.5 Branch connections for 1–1/2 inch and smaller nominal diameter headers. Wherepossible and economical, branch connections shall be made up by using straightor reducing socket weld tee or sockolets. If using a coupling or half coupling, two90º separated gusset strips, welded to pipe, shall be used. Gusset strips shall beof compatible metallurgy of header and branch. For carbon steel, use P–1, P–3,P–4 or P–5 strips (See Figure 3).

6.4.6 Minimum wall thickness for 2 inch or smaller niples.

Material 1–1/2 in NPS or smaller 2 in NPS

Carbon Steel and LowAlloys

Sch 160 Sch 80

Stainless Steel and HighAlloys

Sch 80s Sch 40s

a. All length threaded nipples are not acceptable

b. For 1–1/2 inch and smaller harmful liquid services or vibrating linesconnected to a header with a branch connection, an isolation gate valve shallbe provided, located not beyond than 228 mm (9 inches) from header (SeeFigure 4).

6.4.7 Reinforced branch shall be installed as indicated on drawings and isometrics.Reinforcing plate shall be of compatible material of header. Reinforcing platethickness and dimensions shall be shown on drawings.

6.4.8 Reinforcing plates shall be provided with a vent and pneumatic test 1/8 inch NPTdrilled hole prior to welding.

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6.4.9 A pneumatic test shall be done after welding reinforcing plates, at a pressure of 0,7– 1,03 barg (10 – 15 psig) for at least, 5 minutes. No leaks are permitted. Hole shallbe filled with appropiated grease to prevent from entering water.

7 FIT–UP JOINT

7.1 Line Joints

7.1.1 Non–consumable backing rings shall not be used.

7.1.2 All fit–ups and tack welds must be made to the satisfaction of the Buyer’s Inspector.

7.2 Tee and Lateral Joints

7.2.1 The centerline of the branch connections shall intersect the centerline of theheader.

7.2.2 All cuts shall be carefully beveled and accurately matched to form a good vee (V)for weldings.

7.2.3 Wherever possible, the vee (V) shall have a minimum included angle of 75° tofacilitate obtaining the required complete penetration of welds at all points.

7.2.4 Branch connections in piping that are field fabricated shall be in accordance withPDVSA Engineering Specification H–221, “Piping Materials,” and Owner’sdrawings.

7.2.5 Branch connections in piping that are shop fabricated shall be in accordance withPDVSA Engineering Specification H–221, “Piping Materials”, and Owner’sdrawings.

7.2.6 The Owner’s representative will indicate on drawings the branch reinforcementsrequired for vibration, cyclic, thermal, or special conditions other than pressure.

7.2.7 Sockolets or threadolets may be substituted by socket–weld or threadedcouplings. Weldolets may be substituted by welded–in branches whenever suchsubstitutions meets ASME Codes referenced herein, do not result in increased costand with the approval of Owner’s representative.

7.3 Flanges

7.3.1 Whenever possible, bolt holes of flanges in the vertical lines shall straddle thenorth–south centerline of the pipe in the erected position. For flanges in thehorizontal lines, bolt holes shall straddle the vertical centerline unless otherwiseindicated on the Owner’s drawing.

7.3.2 Orifice flanges shall be welded to pipe with the drilled holes as shown on isometricdrawings.

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7.3.3 Slip–on flanges shall be provided with a vent and pneumatic test 1/8 inch NPTdrilled hole on the neck prior to welding.

7.3.4 A pneumatic test shall be done after welding of slip–on flanges, at a pressure of0,7 – 1,03 barg (10 – 15 psig), for, at least, 5 minutes.

No leaks are permitted. Hole shall be filled with appropriate grease to prevent fromentering water.

8 WELDING

8.1 General

8.1.1 All welding of pressure parts of pipe, whether shop or field, shall be done byqualified welders in accordance with the ASME Boiler and Pressure Vessel Code,ASME Code for Process Piping and Owner’s qualification test.

8.1.2 In addition, the requirements of all jurisdictional codes within which the pipingsystems are to be installed shall be met.

8.1.3 All field welding done by the piping Contractor or Owner shall be in accordance withthe applicable welding procedures approved by Owner.

8.1.4 Each welder or welding operator must successfully pass the PerformanceQualification Test Requirement in exact accordance with the details of the weldingprocedures as submitted.

8.1.5 The piping Contractor shall also be required to conduct welder or welding operatorperformance qualification tests as required by the Owner prior to the start ofproduction welding.

8.2 Welding Process8.2.1 All welding shall be in accordance with ASME B31.3 unless otherwise noted herein.

8.2.2 Welding of pipe over 2 inches in diameter shall be done by an electric arc weldingmethod.

8.2.3 For pipe of 2 inches diameter or smaller, oxyacetylene (for carbon steel only – notfor alloy) or electric arc welding may be used.

8.2.4 Inert gas shielded welding techniques may be used in making the first pass orcomplete weld at the fabricator’s option, unless a specific welding techniques isrequired by the applicable Line Spec. of PDVSA Engineering Specification H–221,“Piping Materials”.

8.3 Welding Electrodes

8.3.1 All electrodes for manual arc welding of steels shall be of heavy flux coated typeconforming to the requirements of ASME–AWS–SFA–5.1 for carbon steel

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electrodes, ASME–AWS–SFA–5.5 for low–alloy steel electrodes andASME–AWS–SFA–5.4 for stainless steel electrodes.

8.3.2 The selection of particular grades shall be made in accordance with Paragraph8.3.4 of this specification, but the brand shall be subject to the approval of theBuyer’s Inspector.

8.3.3 Electrodes and filler metals used in all other welding processes shall meet therequirements of applicable ASME specification.

8.3.4 The brand shall be subject to the approval of the Owner’s representative.

8.4 Selection of Welding Electrodes

8.4.1 Welding electrodes shall be as specified in the applicable welding procedures.

9 HEAT TREATMENTS

9.1 Weldments

9.1.1 The annealing of nickel or chrome–molly steel may be substituted forstress–relieving if approved by the Owner provided that:

a. The welding procedure is qualified in accordance with ASME B31.3 in athickness equal to or greater than the thickness of material to be welded inproduction and the hardness requirements of paragraph 12.2 and ASMEB31.3 are met.

9.1.2 Heating by open torches is not permitted.

9.1.3 Minimum of two thermocouples on each weld are required when stress relievingis done on ferritic alloy steels by localized heating.

9.1.4 Weldments in enclosed furnaces or oil heaters may be given their required thermaltreatments by heating the entire furnace to appropriate temperatures.

9.1.5 Adequate thermocouples shall be used to ensure that all weldments are properlyheated.

9.1.6 Piping shall be heated to a warm hand condition prior to welding when ambienttemperatures are below 10° C (50° F).

9.1.7 Heat treatment is required for all H2S service carbon steel line weldings, except asindicated herein:

a. A solution with a concentration less than 50 ppm.

b. Multiple pass weldings in seamless pipes, done from outer surface only.

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c. External welding elements (gusset strips, clips, pipe supports, etc.), wheredeposited metal does not touch wet H2S

d. Seal multipass weldings

e. Multipass weldings for branch connections, done from outer surface only

9.1.8 Heat treatment is required for all alkaline solution services line weldings, such as:

a. Alkali metal hydroxide caustic solutions, such as sodium or potassiumhydroxide

b. Amines defined as solutions for acid gas absorption or removal of acidiccomponents (i.e. H2S, CO2) from hydrocarbons and hydrogen streams.These include monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA) and FLEXSORB amines.

9.1.9 After heat treatment, no clips, gusset strips, support or any element shall bewelded to pipe wall, unless affected area be heat treated again following ASMECode requirements.

9.2 Special Heat TreatmentsStress relief for welds and bends in caustic service:

a. All stress relieving shall be done after pipe is finished welding and/or bending.

b. Welds and bends shall be heated to a temperature of 593° C and held therefor one hour.

c. Welds and bends should then be cooled in still air.

10 FINAL CORRECTIONS10.1 For carbon steel pipe, if any additional bending is required after the completion of

fabrication to meet dimensional requirements, such bending or correcting may bemade by any suitable method subject to the approval of the Owner’s Inspector.

10.2 For austenitic alloy pipe, and ferritic alloy steel pipe after final heat treatment, allcorrections must be made cold without the application of any heat.

10.3 If it is impossible to make the correction in ferritic alloy pipe cold, the piece shouldbe heated by a controlled method to 680° C to a maximum of 730° C.

11 TOLERANCES11.1 See Figure 1, Dimensional Tolerances.

12 INSPECTION AND TESTS

12.1 Inspection of Welds12.1.1 All welds shall be subject to the inspection requirements of ASME B31.3.

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12.1.2 The standards of acceptability for all radiographs shall be ASME B31.3.

12.1.3 All joints subject to 100% radiographic inspection shall have complete penetration.

12.1.4 For welds made with inert gas welding techniques, which are subject toradiographic inspection, the radiographic standard of acceptability shall includeadditional requirements as follows:

a. The root of the weld shall show a smooth contour and no evidence ofnon–fused land at the edges of the base material.

b. “Sink” or depression of the root pass shall not result in a total thickness,including weld reinforcement, which is less than the original wall thickness ofthe material being welded. The total length of depression of the root pass shallnot exceed 20% of the circumference of the pipe.

12.2 Hardness Test12.2.1 Hardness tests shall be made on all chrome, chrome–molly, and nickel alloy steel

piping after heat treatment.

12.2.2 Brinnell hardness tests shall be made on a minimum of 10% of the welds or bendsfrom each furnace heat treatment charge and on each locally heat treated section.

12.2.3 The hardness test shall be made on the surface of material affected by the bendingor welding operations and shall show hardness numbers not to exceed the valuespermitted by ASME B31.3 on stress–relieved weldments and 180 Brinnell onannealed bends.

12.3 Hydrostatic Pressure Test for Piping Sub–Assemblies12.3.1 No shop hydrostatic testing shall be required for any sub–assemblies fabricated

in accordance with this Engineering Specification.

12.3.2 These sub–assemblies and field fabricated piping shall be hydro–statically testedin the field in accordance with Engineering Procedure PDVSA PI–02–08–01,“Pruebas Hidrostáticas y Neumáticas para Sistemas de Tuberías”.

12.4 Dimensional CheckBefore preparation for shipment, all parts and dimensions for each piece offabricated pipe supplied by piping sub–assembly contractor shall be checked tomake sure the final fabrication meets all the requirements of the Owner’s drawingsand this Engineering Specification.

13 SHIPMENT

13.1 Preparation for Shipment13.1.1 All pipe shall be dry and free from all water, dirt, and loose foreign materials.

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a. All hot bends must be turbined or otherwise cleaned to completely remove alladherent burned–on sand.

b. Special cleaning, such as sandblasting and chemical cleaning shall be doneonly when required by the applicable Line Spec. of PDVSA EngineeringSpecification H–221, “Piping Materials”.

c. Acid cleaning is not permitted on stainless steel piping.

d. Brushes or pads used on stainless steel shall be stainless steel and used onlyfor stainless steel.

13.1.2 All flange faces, thread ends, and other machined surfaces of all piping materialsshall be coated with grease type rust preventative applied as recommended by themanufacturer. The brand of grease used must be approved by the Owner’sInspector.

13.1.3 All flange faces shall be protected against damage in shipment by suitable coversof wood or plastic.

a. The covers shall be securely and tightly attached by at least three bolts or bywiring through at least four bolt holes.

b. Threaded ends shall be provided with plastic thread protectors.

c. Beveled ends shall be protected with plastic caps.

13.2 Spool Piece Marking

13.2.1 The appropriate pipe identification consisting of the line number and spool numbershall be legibly painted on each pipe spool in large block figures.

13.2.2 In addition, each pipe spool shall be identified with the line number and spoolnumber stamped on the edge of a flange using steel stencils.

13.2.3 If a spool piece contains no flanges, the steel stencil identifying marks shall bestamped on the pipe at one end.

13.2.4 Steel stencil marks are not permitted on Charpy impact tested carbon steel oraustenitic stainless steel piping or components.

13.2.5 In place of steel stencil marks on the pipe, stamped metal tags shall be securelyfastened to stainless steel spools.

13.2.6 Steel stencil identification marks on ferritic alloy steels shall be applied prior to heattreatment.

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Fig 1. DIMENSIONAL TOLERANCES

51111

1

1

4

3

2

3

4

2

1

5

ITEM NORMALSERVICE

SPECIAL SERVICESa. Design Temperature �

850 °F or Flange Rating� ASME Class 900

b. Where plastic orelastomeric lines (lappedover the flange faces)provides the gasket forthe joint

c. Piping over NPS 3 to beconnected to rotatingmachinery

�1/8 in. max. from indicated dimensions for face to face, center to face, location of attachments, etc.

Bend flattening tolerance shall be in accordance with theapplicable code

�1/8 in. maxlateral translationof branches orconnections

�1/16 in. max. rotation of flanges from the indicated position,measured as shown.

�1/64 in. for piping over NPS 3 to be connected to rotatingmachinery

Per the applicableCode

�1/64 in. max. out of alignment of flangesfrom the indicated position, measured acrossany diameter

�1/16 in. max. lateral translation of branchesor connections.

ACCEPTABLE METRIC EQUIVALENTS

IN. 1.64 1.16 1/8 850°F NPS 3

MM 0.4 1.5 3 454°C 80

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Fig 2. LIMITATIONS ON MAXIMUM MITER ANGLE

TWO WELD MITER

THREE WELD MITER

FOUR WELD MITER

� 200 PSIG

� 400 PSIG

> 400 PSIG

MAXIMUM PERMISSIBLE DESIGN PRESSURE

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Fig 3.

Flanged Connection Reinforcementwith Gussets

Reinforcement with Gussets

Note: Minimize the distance from the main line to the valve or weight

Use ReinforcementPad with Gussets

Weld Gussetsto Strap

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Fig 4.

Two plane gusseting

9 in max.(228 mm)

General Note:Bracing detail appliable to extended body type valve,or compact body valve plus nipple (as illustrated)

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h-231

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