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sa-234

SPECIFICATION FOR PIPING FITTINGS OF WROUGHT CARBON STEEL AND ALLOY STEEL FOR MODERATE AND ELEVATED TEMPERATURES

SA-234/SA-234M

(Identical with ASTM Speciﬁcation A234/A234M-95a.)

1.Scope

1.1This speciﬁcation covers wrought carbon steel and

alloy steelﬁttings of seamless and welded construction

covered by the latest revision of ANSI B16.9,ANSI

B16.11,ANSI B16.28,MSS SP-79,and MSS SP-95.

Theseﬁttings are for use in pressure piping and in

pressure vessel fabrication for service at moderate and

elevated temperatures.Fittings differing from these

ANSI and MSS standards shall be furnished in accord-

ance with Supplementary Requirement S9.

1.2Optional supplementary requirements are provided

forﬁttings where a greater degree of examination is

desired.When desired,one or more of these supplemen-

tary requirements may be speciﬁed in the order.

1.3This speciﬁcation does not cover cast welding

ﬁttings orﬁttings machined from castings.Cast steel

weldingﬁttings are governed by Speciﬁcations A216/

A216M and A217/A217M.

1.4This speciﬁcation is expressed in both inch-

pound units and in SI units.However,unless the order

speciﬁes the applicable“M”designation(SI units),the

针织牛仔布material shall be furnished to inch-pound units.

1.5The values stated in either inch-pound units or

SI units are to be regarded separately as standard.

Within the text,the SI units are shown in brackets.The

values stated in each system are not exact equivalents;

therefore,each system must be used independently of

the other.Combining values from the two systems may

result in nonconformance with the speciﬁcation.

353

2.Referenced Documents

2.1ASTM Standards:

A216/A216M Speciﬁcation for Steel Castings,Carbon,

Suitable for Fusion Welding,for High-Temperature

Service

A217/A217M Speciﬁcation for Steel Castings,Marten-

sitic Stainless and Alloy,for Pressure-Containing Parts

Suitable for High-Temperature Service

A370Test Methods and Deﬁnitions for Mechanical Test-

ing of Steel Products

A751Test Methods,Practices,and Terminology for

Chemical Analysis of Steel Products

E165Practice for Liquid Penetrant Inspection Method

E709Practice for Magnetic Particle Examination

2.2ANSI Standards:

B16.9Steel Butt-Welding Fittings

B16.11Forged Steel Fittings,Socket Welding and

Threaded

B16.28Wrought Steel Butt-Welding Short Radius El-

bows and Returns

2.3ASME Boiler and Pressure Vessel Code:

Section V Nondestructive Examination

Section VIII,Division1,Pressure Vessels

内河航标灯Section IX Welding Qualiﬁcations

2.4MSS Standards:

MSS SP-25Standard Marking System for Valves,Fit-

tings,Flanges,and Unions

MSS SP-79Socket Welding Reducer Inserts

MSS SP-95Swage(d)Nipples and Bull Plugs

SA-234/SA-234M1998SECTION II

2.5ASNT Standard:

SNT-TC-1A(1984)Recommended Practice for Nonde-structive Testing Personnel Qualiﬁcation and Certiﬁ-cation

3.Ordering Information

3.1Orders for material under this speciﬁcation shall include the following information:

3.1.1Quantity(number ofﬁttings of each kind),

3.1.2Description ofﬁtting and nominal dimensions (standard or special),

3.1.3Steel composition by grade and class desig-nation,

3.1.4Construction,seamless or welded(unless seamless or welded construction is speciﬁed by the purchaser either may be furnished at the option of the supplier),

3.1.5Additional requirements,if any,(See 17.5),and

3.1.6Supplementary requirements,if any.

4.Materials

4.1The material forﬁttings shall consist of killed steel,forgings,bars,plates,seamless or fusion-welded tubular products withﬁller metal added and shall con-form to the chemical requirements of Table1.Unless otherwise speciﬁed for carbon steel plates,the steel may be made to either coarse grain orﬁne grain practice.

4.2A starting material speciﬁcation that speciﬁcally requires the addition of any element beyond those listed

for the materials in Tables1and2and for the applicable grade of material is not permitted.This does not preclude the use of deoxidizers or the judicious use

of elements for grain size control.

5.Manufacture

5.1Forging or shaping operations may be performed

by hammering,pressing,piercing,extruding,upsetting, rolling,bending,fusion welding,machining,or by a combination of two or more of these operations.The forming procedure shall be so applied that it will not produce injurious imperfections in theﬁttings.

354

5.2Fittings machined from bar shall be restricted to NPS4or smaller.Elbows,return bends,tees,and header tees shall not be machined directly from bar stock.

NOTE1—Fittings NSP-4and under may be machined from hot-forged or rolled,cold-sized,and straightened bar stock having the chemical composition of the grade in Table1and the mechanical properties of the Grade in Table 2.Heat treatment shall be in accordance with Section6.All caps machined from bar stock shall be examined with by liquid penetrant or magnetic particle in accord-ance with S3or S4.

5.3All welds including welds in tubular products from whichﬁttings are made shall be(1)made by welders,welding operators,and welding procedures qualiﬁed under the provisions of ASME Section I

X, (2)heat treated in accordance with Section6of this speciﬁcation,and(3)radiographically examined throughout the entire length of each weld in accordance with Article2,ASME Section V with acceptance limits in accordance with Paragraph UW-51of ASME Section VIII,Division1of the ASME Boiler Pressure Vessel Code.In place of radiographic examination,welds may be ultrasonically examined in accordance with Appendix 12of Section VIII.The NDE of welds in Grades WPB, WPC,WP1,WP11Class1,WP11Class2,WP11 Class3,WP12Class1,WP12Class2,and WPR may be performed either prior to or after forming.NDE of welds in Grades WP5,WP9,WP91,WP22Class1, and WP22Class3shall be done after forming.

5.4Personnel performing NDE examinations shall be qualiﬁed in accordance with SNT-TC-1A.

5.5The welded joints of theﬁttings shall beﬁnished in accordance with the requirements of Paragraph UW-35(a)of ASME Section VIII,Division1.

5.6All butt-weld tees manufactured by cold-forming method(s)shall be liquid penetrant or magnetic particle examined by one of the methods speciﬁed in Supplemen-tary Requirement S3or S4.This examination shall be performed afterﬁnal heat treat.Only the side wall area of the tees need be examined.This area is deﬁned by a circle that covers the area from the weld bevel of the branch outl

et to the center line of the body or run. Internal and external surfaces shall be examined when size permits accessibility.No cracks shall be permitted. Other imperfections shall be treated in accordance with Section12on Surface Quality.After the removal of any crack,the tee(s)shall be re-examined by the original method.Acceptable tees shall be marked with the symbol PT or MT,as applicable,to indicate compliance.

PART A—FERROUS MATERIAL SPECIFICATIONS SA-234/SA-234M

6.Heat Treatment

6.1Heat Treatment Procedures—Fittings,after forming at an elevated temperature,shall be cooled to

a temperature below the critical range under suitable conditions to prevent injuries by too rapid cooling,but

in no case more rapidly than the cooling rate in still air.Heat-treatedﬁttings shall be treated according to

the following procedures:

6.1.1Full Annealing—Fittings shall be uniformly reheated to a temperature above the transformation range and after being held for a sufﬁcient time at this temperature,cooled slowly to a temperature below the transformation range.

6.1.2Isothermal Annealing—Isothermal annealing

as applied toﬁttings shall involve austenitizing a ferrous alloy and then cooling to and holding within the range

of temperature at which the austenite transforms to a relatively soft ferrite-carbide aggregate.

6.1.3Normalizing—Fittings shall be uniformly reheated to a temperature above the transformation range and subsequently cooled in air at room temperature.

6.1.4Tempering and Post-Weld Heat Treatment—Fittings shall be reheated to the prescribed temperature below the transformation range,held at temperature for

the greater of1⁄2h or1h/in.[2.4min/mm]of thickness

at the thickest section and cooled in the furnace or in

still air.

6.1.5Stress Relieving—Fittings shall be uniformly heated;temperature shall not vary by more thanϮ25°F [Ϯ14°C]from the selected stress relieving temperature. 6.2WPB,WPC,and WPR Fittings:

6.2.1Hot-formed WPB,WPC,and WPRﬁttings upon which theﬁnal forming operation is completed

at a temperature above1150°F[620°C]and below 1800°F[980°C]need not be heat treated provided they

are cooled in still air.If the manufacturer elects to heat treat suchﬁttings,it shall be by one of the procedures deﬁned in6.1through6.1.4.

6.2.2Hot-formed or forged WPB,WPC,and WPR

ﬁttingsﬁnished at temperature in excess of1800°F [980°C]shall subsequently be annealed,normalized,or normalized and tempered.Hot-forgedﬁttings NPS4

or smaller need not be heat treated.

6.2.3WPB,WPC,and WPRﬁttings produced by locally heating a portion of theﬁtting stock to any temperature for forming shall be subsequently annealed, normalized,or normalized and tempered.Fittings such

as elbows,tees,header tees,reducers and lap joint

355stub ends,NPS12and under,shall not require heat treatment after forming a locally heated portion of the ﬁtting.

6.2.4Cold-formed WPB,WPC,and WPRﬁttings, upon which theﬁnal forming operation is completed at a temperature below1150°F[620°C]shall be normal-ized,or shall be stress relieved at1100to1275°F[595 to690°C].

6.2.5WPB,WPC,and WPRﬁttings produced by fusion welding and having a nominal wall thickness at the welded joint of3⁄4in.[19mm]or greater shall be post-weld heat treated at1100to1250°F[595to 674°C],or in accordance with6.2.6.

6.2.6At the option of the manufacturer,WPB and WPCﬁttings produced by any of the methods in Section 5may be annealed,normalized,or normalized and tempered.

6.3Fittings Other than WPB,WPC,and WPR:

6.3.1Fittings of Grades WP1,WP11Class1, WP11Class2,WP11Class3,WP12Class1,WP12 Class2,WP22Class1,WP22Class3,WP5,and WP9shall be furnished in the full-annealed,isothermal-annealed,or normalized and tempered condition.If normalized and tempered,the tempering temperature for WP11Class1,WP11Class2,WP11Class3, WP12Class1,and WP12Class2shall not be less than1150°F[620°C];for Grades WP5,WP9,WP22 Class1,and WP22Class3the tempering temperature shall not be less than1250°F[675°C].

6.3.2Fittings of Grades WP1or WP12Class2 either hot formed or cold formed may be given aﬁnal heat treatment at1200°F[650°C]instead of the heat treatment speciﬁed in6.3.1.

6.3.3Fittings in all thicknesses produced by fusion welding after the heat treatment speciﬁed in6.3.1shall be post-weld heat treated at a temperature not less than prescribed above for tempering except that Grade WP1 is required to be post-weld heat treated only when the nominal wall thickness at the welded joint is1⁄2in. [13mm]or greater.

6.3.4Except when Supplementary Requirement S12is speciﬁed by the purchaser,Grade WP91shall be normalized at1900°F[1040°C]minimum,and2000°F [1095°C]maximum,and tempered at1350°F[73

0°C] minimum as aﬁnal heat treatment.

6.4WPB and WPC Fittings Made from Bar—Cold-ﬁnished bars reduced in cross-sectional area more than 10%by cold drawing or cold rolling are not acceptable

SA-234/SA-234M1998SECTION II

反光道钉

for use in the manufacture of theseﬁttings unless the bars have been either stress relieved in the temperature range of1100to1250°F[595to675°C],normalized, normalized and tempered,or fully annealed.Mechanical testing must be performed subsequent to theﬁnal heat-treating operation.

6.5Liquid quenching followed by tempering shall

be permitted for all grades when approved by the purchaser.Minimum tempering temperature shall be 1100°F[595°C]for WPB,WPC,and WPR,1150°F [620°C]for Grades WP1,WP11Class1,WP11Class 2,WP11Class3,WP12Class1,and WP12Class2 and1250°F[675°C]for Grades WP5,WP9,WP22 Class1,and WP22Class3,and1350°F[730°C]for Grade WP91.

7.Chemical Composition

7.1The chemical composition of each cast or heat used shall be determined and shall conform to the requirements of the chemical composition for the respec-tive materials listed in Table1.The ranges as shown have been expanded to include variations of the chemical analysis requirements that are listed in the various speciﬁcations for the starting materials(pipe,tube,plate, bar,and forgings)normally used in the manufacturing

ofﬁttings to this speciﬁcation.Test Methods,Practices, and Terminology A751shall apply.

7.2Weld metal used in the construction of carbon-steelﬁttings shall be mild steel analysis No.A1of Table QW-442,Section IX of the ASME Boiler and Pressure Vessel Code;No.A2may be used for Grade WPCW.

7.3The molybdenum and chromium content of the deposited weld metal of alloy steelﬁttings shall be within the same percentage range as permitted for the base metal.

8.Tensile Requirements

8.1The tensile properties of theﬁtting material shall conform to the requirements listed in Table 2.The testing shall be performed in accordance with Test Methods and Deﬁnitions A370.

8.1.1Specimens cut either longitudinally or trans-versely shall be acceptable for the tension test.

单顶置凸轮轴

8.1.2While Table2speciﬁes elongation require-ment for both longitudinal and transverse specimens,

it is not the intent that both requirements apply simulta-

356neously.Instead,it is intended that only the elongation requirement that is appropriate for the specimen used be applicable.

8.2One tension test shall be made on each heat of material and in the same condition of heat treatment as theﬁnishedﬁttings it represents.The sample thick-ness shall not vary more than1⁄4in.[6mm]from the ﬁtting wall thickness it represents.

8.3When cold-formedﬁttings are furnished,samples of the raw material shall be normalized or stress relieved as required in6.2.4.Tension tests conducted on these heat-treated samples shall be considered to be the tensile properties of the cold-formedﬁttings.

8.4Records of the tension tests shall be certiﬁcation that the material of theﬁtting meets the tensile require-ments of this speciﬁcation provided the heat treatments are the same.If the raw material was not tested,or theﬁtting is not in the same condition of heat treatment, theﬁtting manufacturer shall per

form the required test on material representative of theﬁnishedﬁtting from each heat of starting material.

9.Hardness

9.1Fittings shall be capable of meeting the following hardness requirements,if tested:足球袜

9.1.1Fittings of Grades WP5,WP9,and WPR—217HB maximum.

9.1.2Fittings of Grade WP91—248HB maximum.

9.1.3Fittings of all other grades—197HB maximum.

9.2When actual hardness testing of theﬁttings is required,see Supplementary Requirement S8.

10.Hydrostatic Tests

10.1Hydrostatic testing is not required by this speci-ﬁcation.

10.2Allﬁttings shall be capable of withstanding without failure,leakage,or impairment of their service-ability,a hydrostatic test pressure equal to that pre-scribed for the speciﬁed matching pipe of equivale

nt material.

PART A—FERROUS MATERIAL SPECIFICATIONS SA-234/SA-234M

11.Dimensions

11.1Butt-weldingﬁttings and butt-welding short radius elbows and returns purchased in accordance with this speciﬁcation shall conform to the dimensions and tolerances given in the latest revision of ANSI B16.9and

B16.28,respectively.Steel socket-welding and threaded

ﬁttings purchased in accordance with this speciﬁcation shall conform to the sizes,shapes,dimensions,and tolerances speciﬁed in the latest revision of ANSI

B16.11or MSS SP-79.

11.2Fittings of size or shape differing from these standards,but meeting all other requirements of this speciﬁcation may be furnished in accordance with Sup-plementary Requirement S9.

12.Surface Quality

12.1Fittings supplied under this speciﬁcation shall

be examined visually.Selected typical surface disconti-nuities shall be explored for depth.Theﬁttings shall患者腕带

be free of surface discontinuities that penetrate more than5%of the speciﬁed nominal wall thickness,except

as deﬁned in12.3and12.4,and shall have a workman-likeﬁnish.

12.2Surface discontinuities deeper than5%of the speciﬁed nominal wall thickness,except as deﬁned in 12.3and12.4,shall be removed by the manufacturer

by machining or grinding to sound metal,and the repaired areas shall be well faired.The wall thickness

at all points shall be at least871⁄2%of the speciﬁed nominal wall thickness,and the diameters at all points shall be within the speciﬁed limits.

12.3Surface checks(ﬁsh scale)deeper than1⁄64in. [0.4mm]shall be removed.

12.4Mechanical marks deeper than1⁄16[1.6mm] shall be removed.

12.5When the removal of a surface discontinuity reduces the wall thickness below871⁄2%of the speciﬁed nominal wall thickness at any point,theﬁtting shall

be subject to rejection or to repair as provided in Section13.

13.Repair by Welding

13.1Theﬁttings manufacturer may weld repairﬁt-tings,subject to the approval of the purchaser,provided

the composition of the welding material is suitable for

the composition of the metal being welded.Repair by welding shall not be permitted when the depth of

357the discontinuity exceeds331⁄3%of the nominal wall thickness or the length exceeds25%of the nominal diameter of theﬁttings.Discontinuities shall be com-pletely removed before welding.All welds shall be made by welders,welding operators,and welding procedures qualiﬁed under the provisions of ASME Section IX and heat treated after welding in accordance with Section6.

14.Inspection

14.1The manufacturer shall afford the purchaser’s inspector all reasonable facilities necessary to satisfy him that the material is being furnished in accordance with this speciﬁcation.Inspection by the purchaser shall not interfere unnecessarily with the manufacturer,unless otherwise agreed to.

14.2Other tests,when required by agreement,shall be made from material of the lots covered in the order.

15.Rejection and Rehearing

15.1Material that fails to conform to the requirements of this speciﬁcation may be rejected.Rejection should be reported to the producer or supplier promptly in writing.In case of dissatisfaction with the results of the tests,the producer or supplier may make claim for

a rehearing.

15.2Fittings that develop defects in shopworking or application operations may be rejected.Upon rejection, the manufacturer shall be notiﬁed promptly in writing.

16.Certiﬁcation

16.1When requested by the purchase,the manufac-turer shall provide a certiﬁcate of compliance to this speciﬁcation.In addition,if requested to provide test reports,the manufacturer shall also provide the follow-ing where applicable.

16.1.1Chemical analysis results,Section7(Ta-ble1),

16.1.2Tensile property results,Section8(Table 2),report the yield strength and ultimate strength in ksi[MPa]and elongation in percent,

16.1.3Hardness acceptable in accordance with Section9,

16.1.4Type heat treatment,if any,Section6,

16.1.5Seamless or welded,

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