Designation:A 352/A 352M –03
Standard Specification for
Steel Castings,Ferritic and Martensitic,for Pressure-Containing Parts,Suitable for Low-Temperature Service 1
This standard is issued under the fixed designation A 352/A 352M;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A nu
mber in parentheses indicates the year of last reapproval.A superscript epsilon (e )indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.
1.Scope *
1.1This specification 2covers steel castings for valves,flanges,fittings,and other pressure-containing parts intended primarily for low-temperature service.
1.2Several grades of ferritic steels and one grade of martensitic steel are covered.Selection of analysis will depend on design and service conditions (Note).The temperature shown is the lowest temperature at which the material ordi-narily is required to meet the impact requirements of this specification (see Supplementary Requirement S22,Impact Test Temperatures).Users should note that hardenability of some of the grades mentioned may restrict the maximum size at which the required mechanical properties are obtainable (see Appendix X1).
Grade Usual Minimum Testing Temperatures,°F [°C]
LCA −25[–32]LCB −50[–46]LCC −50[–46]LC1−75[–59]LC2−100[–73]LC2–1−100[–73]LC3−150[–101]LC4−175[–115]LC9−320[–196]CA6NM
−100[−73]
N OTE 1—This specification covers the low-temperature requirements particularly pertinent for ferritic and martensitic steels.Certain of the grades of austenitic steel castings furnished in accordance with Specifi-cation A 351/A 351M have been found suitable for low-temperature service down to −300°F [−184°C]and others down to −425°F [−254°C].These grades may be used when impact tested in accordance with Specification A 352/A 352M with energy levels and temperatures of test mutually agreed upon between the purchaser and the manufacturer.As a guide to the selection of energy levels and testing temperatures,Appendix X1should be consulted.
1.3The 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 specifi-cation.Inch-pound units are applicable for material ordered to Specification A 352and SI units for material ordered to Specification A 352M.
2.Referenced Documents 2.1ASTM Standards:
A 351/A351M Specification for Castings,Austenitic,Aus-tenitic–Ferritic (Duplex),for Pressure–Containing Parts 3A 370Test Methods and Definitions for Mechanical Testing of Steel Products 4
A 488/A488M Practice for Steel Castings,Welding,Quali-fications of Procedures and Personnel 3
A 703/A703M Specification for Steel Castings,General Requirements,for Pressure-Containing Parts 3
E 165Test Method for Liquid Penetrant Examination 5E 709Guide for Magnetic Particle Examination 5
2.2Manufacturers’Standardization Society of the Valve and Fittings Industry Standard:
SP-55Quality Standard for Steel Castings for Valves,Flanges,and Fittings and Other Piping Components (Vi-sual Method)63.General Conditions for Delivery
3.1Material furnished to this specification shall conform to the requirements of Specification A 703/A 703M including any supplementary requirements that are indicated in the purchase order.Failure to comply with the general requirements of Specification A 703/A 703M constitutes nonconformance with this specification.In case of conflict between the requirements
cracks什么意思中文1
This specification is under the jurisdiction of ASTM Committee A01on Steel,Stainless Steel,and Related Alloys and is the direct responsibility of Subcommittee A01.18on Castings.
Current edition approved May 10,2003.Published May 2003.Originally approved in 1952.Last previous edition approved in 1998as A 352/A 352M –93(1998).2
For ASME Boiler and Pressure Vessel Code applications,see related Specifi-cation SA-352,in Section II of that Code.
3
Annual Book of ASTM Standards ,V ol 01.02.4Annual Book of ASTM Standards ,V ol 01.03.5
Annual Book of ASTM Standards ,V ol 03.03.6
Available from Manufacturers’Standardization Society of the Valve and Fittings Industry,127Park St.,North East Vienna,V A 22180.
1
*A Summary of Changes section appears at the end of this standard.
Copyright ©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United
States.
of this specification and Specification A703/A703M,this specification shall prevail.
4.Ordering Information
4.1The inquiry and order should include or indicate the following:
4.1.1A description of the casting by pattern number or drawing(dimensional tolerances shall be included on the casting drawing),
4.1.2Grade of steel,
4.1.3Options in the specification,and
4.1.4The supplementary requirements desired,including the standards of acceptance.
5.Heat Treatment
5.1All castings shall receive a heat treatment proper to their design and chemical composition.It should be recognized that liquid quenching of the ferritic grades is normally required to meet the mechanical properties of heavier sections and will greatly enhance the low-temperature properties of thinner sections.
5.2Ferritic castings shall be furnished in the normalized and tempered or liquid-quenched and tempered condition,except for Grade LC9,which shall be liquid-quenched and tempered. Castings shall be tempered at a minimum of1100°F[590°C], except Grade LC4,which shall be1050°F[565°C],and Grade LC9,which shall be tempered in the range of1050to1175°F [565to635°C],followed by cooling in air or liquid.
5.3CA6NM castings shall be heat-treated by heating to 1850°F[1010°C]minimum,and air cooling to200°F[95°C] maximum before any optional intermediate temper,but shall cool to100°F[40°C]maximum before thefinal temper,which shall be between1050and1150°F[565and620°C].
5.4Castings shall be allowed to cool below the transforma-tion range directly after pouring and solidification before they are reheated for normalizing or liquid quenching.
5.5Temperature Control—Furnace temperature for heat treating shall be controlled by use of pyromete
rs.
6.Chemical Composition
6.1The steel shall conform to the requirements as to chemical composition for the grade ordered as specified in Table1.
7.Mechanical Requirements
7.1Tension Test:
7.1.1Tensile properties of steel used for the castings shall conform to the requirements specified in Table1.
7.2Impact Test:
7.2.1The notched bar impact properties of the material shall be determined by testing a set of three Charpy V-notch impact specimens for each heat at one of the standard test temperatures shown in Table1,depending on the intended service tempera-ture(see Appendix X1).The average energy value of the three specimens shall not be less than specified,with not more than one value permitted below t
he average minimum specified and no value permitted below the minimum specified for a single specimen.
7.2.2The notched bar impact test shall be made in accor-dance with Test Methods and Definitions A370.
7.2.3Impact test specimens shall be machined to the form and dimensions shown in Test Methods and Definitions A370, Type A,Charpy V-Notch specimens,Fig.11.
8.Quality
8.1The surface of the casting shall be examined visually and shall be free of adhering sand,scale,cracks,and hot tears. Other surface discontinuities shall meet the visual acceptance standards specified in the order.Visual Method SP-55or other visual standards may be used to define acceptable surface discontinuities andfinish.Unacceptable visual surface discon-tinuities shall be removed and their removal verified by visual examination of the resultant cavities.When methods involving high temperature are used in the removal of discontinuities, castings shall be preheated to at least the minimum tempera-tures in Table2.
8.2When additional inspection is desired,Supplementary Requirements S4,S5,and S10,may be ordered.
8.3The castings shall not be peened,plugged,or impreg-nated to stop leaks.
9.Repair by Welding
9.1Repairs shall be made using procedures and welders in accordance with Practice A488/A488M.
9.2Welding of Grade LC9shall be accomplished using nonmagneticfiller material of AWS classification ENiCrFe-2, and shall require liquid penetrant inspection of the weld (Supplementary Requirement S6)when magnetic particle in-spection(Supplementary Requirement S4)is specified for the casting.
9.3Weld repairs shall be inspected to the same quality standards that are used to inspect the castings.When castings are produced with Supplementary Requirement S4specified, weld repairs shall be inspected by magnetic particle examina-tion to the same standards that are used to inspect the castings. When castings are produced with Supplementary Requirement S5specified,weld repairs on castings that have leaked on hydrostatic tests,or on castings in which the depth of any cavity prepared for repair welding exceeds20%of the wall thickness or1in.[25mm]whichever is smaller,or on c
astings in which any cavity prepared for welding is greater than approximately10in.2[65cm2shall be radiographed to the same standards that are used to inspect the castings.
9.4Castings containing any repair weld that exceeds20% of the wall thickness,or1in.[25mm],whichever is smaller, or that exceeds approximately10in.2[65cm2]in area,or that was made to correct hydrostatic test defects shall be stress relieved or heat treated after welding.This mandatory stress relief or heat treatment shall be in accordance with the procedure qualification used.When stress relief is required for Grade LC9,cooling shall be in still air.
10.Product Marking
10.1All marking shall be on a raised pad using low-stress
stamps.
10.2In addition to the marking required by Specification A 703/A 703M,castings that have been liquid quenched and tempered shall be marked with the letters “QT”.
11.Keywords
11.1alloy steel;carbon steel;ferritic steel;low temperature applications;martensitic stainless steel;pressure containing parts;stainless steel;steel castings
TABLE 1Chemical,Tensile,and Impact Requirements
Type
Carbon Steel
Carbon Steel
Carbon-Manganese Steel
Carbon-Molybdenum
Steel
21/2%Nickel Steel
Nickel-Chromium-Molybdenum
Steel
31/2%Nickel Steel
41/2%Nickel Steel
9%Nickel Steel
121/2%Chromium,Nickel-Molybdenum
Steel Grade LCA LCB A LCC LC1LC2LC2-1LC3LC4LC9CA6NM UNS Number
J02504
J03003
J02505
J12522
J22500
J42215
J31550
J41500
J31300
J91540
Element,%(max,except where range is given)
Carbon 0.25A 0.300.25A 0.250.250.220.150.150.130.06Silicon
0.600.600.600.60
0.60
0.50
0.60
0.60
0.45 1.00Manganese 0.70A 1.00 1.20A 0.50–0.800.50–0.800.55–0.750.50–0.800.50–0.800.90 1.00Phosphorus 0.040.040.040.040.040.040.040.040.040.04Sulfur 0.0450.0450.0450.0450.0450.0450.0450.0450.0450.03Nickel 0.50B 0.50B 0.50B ... 2.00–3.00 2.50–3.50 3.00–4.00 4.00–5.008.50–10.0 3.5–4.5Chromium 0.50B 0.50B 0.50B ...
... 1.35–0.5011.5–14.0Molybdenum 0.200.20B 0.20B 0.45–0.30–0.200.4–1.0Copper 0.300.30B 0.30B ...............Vanadium 0.03B 0.03B 0.03B ...............0.03
...
Tensile
Requirements:C
Tensile strength,ksi [MPa]60.0–85.0[415–585]65.0–90.0[450–620]70.0–95.0[485–655]65.0–90.0[450–620]70.0–95.0[485–655]105.0–130.0[725–895]70.0–95.0[485–655]70.0–95.0[485–655]85.0[585]110.0–135.0[760–930]Yield strength,D
min,ksi [MPa]30.0[205]35.0[240]40.0[275]35.0[240]40.0[275]80.0[550]40.0[275]40.0[275]75.0[515]80.0[550]Elongation 50mm,min,%E
24
24
22
24
24
18
24
24
20
15
Reduction of area,min,%
35353535353035353035
Impact Requirements
Charpy V-Notch C ,F
Energy value,ft·lbf [J],min value for two specimens and min avg of three
specimens 13[18]13[18]15[20]13[18]15[20]30[41]15[20]15[20]20[27]20[27]
Energy value,ft·lbf
[J],min for single specimen
10[14]10[14]12[16]10[14]12[16]25[34]12[16]12[16]15[20]15[20]
Testing temperature,
°F [°C]
−25[−32]−50[−46]−50[−46]−75[−59]−100[−73]−100[−73]
−150
[−101]−175[−115]−320[−196]
−100[−73]
A
For each reduction of 0.01%below the specified maximum carbon content,an increase of 0.04%manganese above the specified maximum will be permitted up to a maximum of 1.10%for LCA,1.28%for LCB,and 1.40%for LCC.B
Specified Residual Elements—The total content of these elements is 1.00%maximum.C
See 1.2.D
Determine by either 0.2%offset method or 0.5%extension-under-load method.E
When ICI test bars are used in tensile testing as provided for in Specification A 703/A 703M,the gage length to reduced section diameter ratio shall be 4to 1.F
See Appendix
X1.
SUPPLEMENTARY REQUIREMENTS
The following supplementary requirements shall not apply unless specified in the purchase order.A list of standardized supplementary requirements for use at the option of the purchaser is included in Specification A 703/A 703M.Those which are ordinarily considered suitable for use with this specificatio
n are given below together with additional supplementary requirements that are applicable only to this specification.Other supplementary requirements enumerated in A 703/A 703M may be used with this specification upon agreement between the manufacturer and purchaser.
S1.Unspecified Elements S2.Destruction Tests
S4.Magnetic Particle Inspection S5.Radiographic Inspection S9.Drop Weight Tests
S10.Examination of Weld Preparation
S10.1The method of performing the magnetic particle or liquid penetrant test shall be in accordance with Practice E 709or Practice E 165.
S21.Heat Treatment
S21.1Castings shall be liquid quenched and tempered.S22.Impact Test Temperatures
S22.1When an impact test temperature other than that listed in Table 1is used,the lowest test temperature at which the material met the impact test requirements shall be stamped
with low-stress stamps on a raised pad located immediately ahead of the material symbol;for example,25LCB for +25°F [–4°C]and 025LCB for –25°F [–32°C].
S22.2Lateral expansion of V-notch specimens shall be measured in accordance with 23.2.3.1of Test Methods and Definitions A 370,and reported for information.
S23.Carbon Equivalent
S23.1When specified on the order the maximum carbon equivalent shall be:
Grade Carbon Equivalent,max
LCA 0.50LCB 0.50LCC
0.55
S23.2Determine carbon equivalent,CE ,as follows:
CE 5C 1Mn 61Cr 1Mo 1V 5
1Ni 1Cu
15APPENDIX
(Nonmandatory Information)
X1.EXPLANATION OF THE USE OF NOTCHED BAR IMPACT TESTS IN DETERMINING THE ACCEPTABILITY OF
STEELS FOR LOW-TEMPERATURE SERVICE
X1.1Years of experience and test work have shown that some materials,particularly ferritic steels,change from tough to brittle behavior with a decrease in temperature.The transi-tion temperatures and the levels of notch toughness vary with different materials,depending on many factors.When materi-als are used under conditions where brittle behavior may occur,there is danger that flaws,which would be considered nonhaz-ardous if the material were tough,may propagate to disastrous
failure of the equipment.
X1.2Accordingly,many varieties of tests have been developed in an effort to evaluate the toughness of materials and the conditions under which they will transform from tough to brittle behavior.There are m
any opinions and shadings of opinion as to which test is most suitable for evaluating the
TABLE 2Minimum Preheat Temperatures
Grade Thickness,in.[mm]
Minimum Preheat Temperature,°F [°C]
LCA all 50[10]LCB all 50[10]LCC all
50[10]LC1over 5/8[15.9]250[120]5/8and under 50[10]LC2all 300[150]LC2-1all 300[150]LC3all 300
[150]LC4all 300[150]CA6NM
all
50
[10]
suitability of materials for service at low temperatures;how-ever,as yet,only the Charpy impact test has received sufficient general acceptance and has been used as a basis for purchasing for sufficient time to be included in ASTM standards.Further-more,this test is required for low-temperature service vessels and piping constructed in accordance with ASME Code for Unfired Pressure Vessels and the American National Standard Code for Pressure Piping (ANSI B 31),respectively.These ASTM specifications for materials for low-temperature service are primarily used in piping and pressure vessel construction that are subjected to temperatures lower than ambient;conse-quently,the notched bar impact test requirements are written to provide material that in quality and by its testing can be validated for use under the construction codes.
X1.3No assurance is offered that compliance with these requirements will provide a material that will resist brittle failure under all possible conditions of service to as low as the specified impact test temperature.It may eventually be possible that other types of tests will provide greater assurance of material suitability for low-temperature services,but at this time there is insufficient knowledge for agreement and general acceptance of some test other than the Charpy impact test.X1.4Attention is directed to the following subjects which have a bearing on the value of Charpy impact tests:
X1.4.1Much of the original work in the field of notch toughness was done on wrought materials that had definite directional grain flow parallel to the axis of the bar,and the specimens were taken with the longitudinal axis of the speci-men parallel to the axis of the bar.It has been well established that the results from impact testing of the same piece of steel may vary considerably,depending upon the orientation of the specimen to the direction of grain flow.Although it is known that specimens taken with their axis transverse to the direction of grain flow will have lower values depending on the amount of cross rolling or forging the material has received,there were insufficient test data to permit specific mandatory requirements on the impact properties of wrought materials determined in any direction other than parallel to the direction of grain flow.Except in special cases this limitation still exists.
X1.4.2It is acknowledged that notched bar impact tests are of a qualitative rather than a quantitative nature.As yet,except possibly for ship steel,no satisfactory correlation has been possible between tests on small standardization specimens and the behavior of a structural part under any given conditions of loading in service.The required values as determined by the Charpy V-notch impact test are arbitrary values which can be met by carbon and low-alloy constructional steels when tested at temperatures above that where their behavior changes from tough to brittle as judged by this test.The acceptability of this dividing line seems to be justified by service experience on carbon and certain low-alloy steels.
X1.4.3The literature shows that notched bar impact strengths in constructional steels differ widely in accordance with many variables.Consequently,there is bound to be some discrepancy between an individual test bar and the entire part that it represents.No system of test bar selection can guarantee that every sample would meet minimum requirements.Test bar selection must be a compromise to generally represent the product.
X1.4.4The committees responsible for these material speci-fications have had as an objective the selection of test speci-mens that will represent the properties of the materials,in the form in which they will be used.However,accomplishment of this objective has only partially been realized.At this time it is impossible to select samples for testing that will represent all parts and sizes of the product involved.Particularly in ferritic steels,it is impractical to remove the test bars from heavy sections over about 4in.[100mm]and expect them to show results as high as tests from light sections of the same material.The practical commercial limits on the amount of testing possible,as well as limits to knowledge of what results may be expected from testing in non-standard locations,have been considered in drafting these specifications.With time and increased knowledge,it may be possible to require more representative testing.
SUMMARY OF CHANGES
Committee A01has identified the location of selected changes to this standard since the last issue (A 352/A 352M –93(1998))that may impact the use of this standard.
(1)Added UNS numbers to Table 1.
ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.Users of this standard are expressly advised that determination of the validity of any such patent rights,and the risk of infringement of such rights,are entirely their own responsibility.
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below.
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