Designation:A395/A395M–99e1
Standard Specification for
Ferritic Ductile Iron Pressure-Retaining Castings for Use at Elevated Temperatures1
This standard is issued under thefixed designation A395/A395M;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number 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.
e1N OTE—Figures4and5were editorially corrected in March2004.
1.Scope
1.1This specification covers ductile iron castings for pressure-retaining parts for use at elevated temperatures.Cast-ings of all grades are suitable for use up to450°F.For temperatures above450°F and up to650°F,only Grade 60–40–18castings are suitable(Note1).
1.2Valves,flanges,pipefittings,pumps,and other piping components are generally manufactured in advance and sup-plied from stock by the manufacturer,jobber,or dealer.
1.3For supplemental casting requirements Specification A834may be utilized.
1.4The 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 shall be used independently of the other.Combining values from the two systems may result in nonconformance to the specification. N OTE1—For service other than as specified in this section,reference should be made to Specification A536for Ductile Iron Castings.2
2.Referenced Documents
2.1ASTM Standards:
A247Test Method for Evaluating the Microstructure of Graphite in Iron Castings2
A370Test Methods and Definitions for Mechanical Testing of Steel Products2
A536Specification for Ductile Iron Castings2
A732/A732M Specification for Castings,Investment,Car-bon and Low Alloy Steel for General Application,and Cobalt Alloy for High Strength at Elevated Temperatures2 A834Specification for Common Requirements for Iron Castings for General Industrial Use2
E8Test Methods for Tension Testing of Metallic Materials3 E10Test Method for Brinell Hardness of Metallic Materi-als3
E186Reference Radiographs for Heavy-Walled(2to41⁄2 in.(51to114-mm))Steel Castings4
E280Reference Radiographs for Heavy-Walled(41⁄2to 12-in.(114to305-mm))Steel Castings4
E446Reference Radiographs for Steel Castings up to2in.
(51mm)in Thickness4
E689Reference Radiographs for Ductile Iron Castings4 E1806Practice for Sampling Steel and Iron for Determi-nation of Chemical Composition5
F1476Specification for Performance of Gasketed Me-chanical Couplings for Piping Applications6
F1548Specification for the Performance of Fittings for Use with Gasketed Mechanical Couplings used in Piping Ap-plications6
2.2Manufacturer’s Standardization Society of the Valve and Fittings Industry Standard:
SP25Standard Marking Systems for Valves,Flanges,Pipe Fittings,and Unions7
3.Classification
3.1Castings ordered to this specification are classified by grades based on mechanical property requirements,as listed in Table1.See note following Table1.
4.Ordering Information
4.1Orders for material under this specification shall include the following applicable information:
4.1.1Drawing,catalog number or part identifications,
4.1.1.1For grade65-45-15,drawing indicating critical ar-ea(s)of casting(see7.2.2and7.3.2).
1This specification is under the jurisdiction of ASTM Committee A-4on Iron Castings and is the direct responsibility of Subcommittee A04.02on Malleable and Ductile Iron Castings.
Current edition approved Dec.10,1999.Published January2000.Originally published as A395–55T.Last previous edition A395–98.
2Annual Book of ASTM Standards,V ol01.02.
3Annual Book of ASTM Standards,V ol03.01.
4Annual Book of ASTM Standards,V ol03.03.
5Annual Book of ASTM Standards,V ol03.06.
6Annual Book of ASTM Standards,V ol01.07.
7Available from the Manufacturers’Standardization Society of the Valves and Fittings Industry,1815N.Fort Myer Drive,Arlington,V A22209.
1
Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.
4.1.2Quantity (weight or number of pieces),4.1.3ASTM designation and year of issue,
4.1.4Grade (See Table 1),if a Grade is not specified,the manufacturer shall supply grade 60-40-18.4.1.5Heat treating requirements (see
5.2.1),4.1.6Pressure test requirements (see 7.4.3),
4.1.7Test samples from castings (see 11.1.1and 12.1.1),4.1.8Test coupons size (see 11.2),
4.1.9Metallographic option (see 12.1.1),4.1.10Place of inspection (see 16.1),
4.1.11Certification requirements (see 17.1),4.1.12Identification marking (see 18.2),and
4.1.13Supplemental Requirements (see 1.4,7.4.2,S1and S2).
5.Materials and Manufacture
5.1The melting method and the nodularizing practice shall be optional with the foundry.
5.2Except as provided in 5.2.1,all castings Grade 60-40-18shall be given a ferritizing heat treatment that produces essentially a ferritic structure that contains no massive car-bides.
5.2.1When specified in the purchase order,Grade 60-40-18castings may be provided in an as cast condition provided they comply with the requirements of 7.1and 7.2.1.
5.2.2Castings supplied in accordance with 5.2.1may be stress relieved by agreement between the manufacturer and purchaser.
5.3Castings Grade 65-45-15may be provided in as cast condition or heat treated,provided they comply with the requirements of 7.1,7.2.2and 7.3.2.
6.Chemical Requirements
6.1The casting shall conform to the following requirements for chemical composition (Note 2):
Total carbon,min,% 3.00Silicon,max,% 2.50Phosphorus,max,%
0.08
6.1.1The chemical analysis for total carbon shall be made on chilled cast pencil type specimens or from thin wafers approximately 1⁄32in.[0.8mm]thick cut from test coupons.Drillings are not reliable because of the probable loss of graphite.
6.1.2For each reduction of 0.01%below the maximum specified phosphorus content,an increase of 0.08%silicon above the specified maximum will be permitted up to a maximum of 2.75%.
N OTE 2—Silicon contents above 2.75%,or phosphorus contents above 0.08%have a tendency to lower the impact resistance of the material.If the carbon content is below 3.00%,excess cementite may form during
cooling and if this is not removed during heat treatment,the impact resistance of the material may be lowered.
7.Requirements
7.1Tensile Properties :
7.1.1The ductile iron as represented by the test specimens shall conform to the mechanical property requirements in Table 1.
7.2Hardness :
7.2.1For Grade 60–40–18the hardness of the castings and test specimens shall be within the limits in Table 1.
7.2.2For Grade 65–45–15the hardness of test specimen and the critical area(s)of the casting,as identified on the casting drawing,shall be within the limits in Table 1.If the grade 65–45–15casting drawing does not have critical area(s)of the casting identified,all areas of the casting shall be within the hardness limits in Table 1.7.3Microstructure :
7.3.1For Grade 60-40-18the microstructure of the sepa-rately cast test coupon or the casting shall be essentially ferritic and contain no massive carbides,and have a minimum of 90%Type I and Type II Graphite as in Fig.1or Plate I of Test Method A 247.
7.3.2For Grade 60-45-15the microstructure of the critical areas of the casting,as identified on the casti
ng drawing,shall be 45%pearlitic,maximum,contain no massive carbides,and have a minimum 90%Type I and Type II Graphite as in Fig.1or Plate I of Test Method A 247.7.4Pressure Test Requirements :
7.4.1Each pressure retaining Grade 60-40-18casting shall be tested after machining to the test pressure specified by the applicable standard of ANSI,ASME Boiler and Pressure Vessel Code,or other pertinent code,and shall show no leaks.7.4.2Castings,Grade 65-45-15manufactured under this specification shall be capable of passing hydrostatic test(s)compatible with the rating of the finished cast component.Such tests shall be conducted by the casting manufacturer only when supplementary requirement S2is specified.
7.4.3Castings Grade 60-40-18,ordered under this specifi-cation not covered by ANSI standards and ASME Pressure Vessel Code,and castings for special service applications,shall be tested to such pressures as may be agreed upon by the manufacturer and the purchaser.
7.4.4For castings Grade 60-40-18,it is realized that the foundry may be unable to perform the hydrostatic test prior to shipment,or that the purchaser may wish to defer testing until additional work or machining has been performed on the casting.Castings ordered in the rough state for final machinin
g by the purchaser may be tested hydrostatically prior to ship-ment by the manufacturer at pressures to be agreed upon with the purchaser.However,the foundry is responsible for the satisfactory performance of the castings under the final hydro-static test.
8.Workmanship and Finish
8.1The surface of the casting shall be examined visually and shall be free from adhering sand,scale,cracks,and hot tears.Any other surface discontinuities shall meet visual acceptance standards specified in the order.
TABLE 1Mechanical Property Requirements
Property
Grade 60-40-18Grade 65-45-15Tensile Strength Minimum,Psi [MPa]60000[415]65000[450]Yield Strength Minimum,Psi [MPa]40000[275]
45000[310]
Elongation in 2in.Minimum,%1815Hardness HB,3000Kgf Load
143-187
156-201
NOTE—If a grade is not specified in the ordering information,grade 60–40–18will be
supplied.
9.Repair
9.1Castings for valves,flanges,pipe fittings,pumps,and other piping components ordered under applicable ANSI stan-dards shall not be repaired by plugging,welding,brazing,or impregnation.
9.2Castings Grade 60-40-18not covered in 9.1which leak on hydrostatic tests may be repaired by plugging,provided the following requirements are met:
9.2.1No welding or brazing is permitted.
9.2.2The diameter of the plug shall not exceed the diameter of a standard 2in.[ISO R2]pipe plug.
9.2.3The plugs,where practical,shall conform in all dimensions to the standard ISO 3⁄8plugs.In addition,they shall have full thread engagement corresponding to the thick-ness in the repaired section.Where a tapered plug is imprac-tical because of the excess wall thickness in terms of plug diameter and coincident thread engagement,other types of plugs may be used provided both full engagement and effective sealing against pressure are obtained.Where possible,the ends of the plug should be ground smooth after installation to conform to the inside and outside contours of the wall of the pressure vessel or pressure part.
9.2.4The material from which the plug is manufactured shall conform in all respects to the materials specifications which apply to the pressure vessel or pressure part.
9.2.5The area adjacent to the drilled hole shall be examined by radiography,and shall meet the Level 3acceptance require-ments of Reference Radiographs E 689and supporting Refer-ence Radiographs E 446,E 186,or E 280as applicable and defined in accordance with Reference Radiographs E 689.9.2.6The thickness of any repaired section in relation to the size of the plug used shall not be less than that given in Table 2.
9.2.7The minimum radius of repaired sections of cylinders or cones in relation to the size of plug used shall not be less than that given in Table
3.
N OTE —Graphite types are identical with Plate 1of Method A 247and are so identified.
FIG.1Suggested Classification of Graphite Form in Ductile Cast
Iron
9.2.8A repaired area may consist of a maximum of three plugs with a spacing such that the ligaments between adjacent plugs shall not be less than listed in Table 4.Other defective areas may also be repaired by plugging provided the minimum ligament between plugs in adjacent areas is not less than twice the distance from the nearest plug,the values for which are listed in Table 4.
9.3Surface imperfections in castings Grade 60-40-18other than valves,flanges,pipe fittings,pumps,and other piping components may be repaired by plugging provided the depth of the plug is not greater than 20%of the thickness of the casting section and the diameter of the plug is not greater than its length.Repair of surface defects may not be done on pressure containing portions of castings.The plug
need not be threaded.The conditions of 9.2.1and 9.2.4shall also be satisfied.10.Sampling
10.1A lot shall consist of one of the following:
10.1.1All the metal from a single heating in a batch—type melting furnace.
10.1.2All the metal poured from two or more batch-type melting furnaces into a single ladle or a single casting.
10.1.3All the metal poured from a continuous melting furnace for a given period of time between changes in charge,processing conditions,or aim-for chemistry,or 8h,whichever is the shorter period.
11.Test Coupon
11.1The separately cast test coupons poured from the same lot as the castings they represent from which the tension test specimen is machined shall be cast to the size and shape shown in Fig.2,Fig.3,or Fig.4.Cast coupons shall be identified with the castings they represent.Sectioning procedure for removing test specimens from Y-blocks is shown in Fig.5.
11.1.1Test samples may be removed from castings at locations designated on a drawing or as agreed to by manu-facturer and purchaser.
11.1.2Test bars removed from castings shall conform to Fig.6.The testing diameter shall be 1⁄2in.[12.5mm]if possible.Smaller diameters shall be utilized if necessary.11.2The test coupon size shall be as mutually agreed upon between the manufacturer and purchaser.In the absence of agreement,it shall be the option of the manufacturer.
11.3The test coupons shall be cast in molds made of suitable core sand having a minimum wall thickness of 11⁄2in.[38mm]for the 1⁄2in.[12.5mm],1in.[25mm]sizes,and 3in.[75mm]for the 3in.[75mm]size.The coupons shall be left in the mold until they have changed to a black color (approximately 900°F [480°C]or less).The keel block as shown in Fig.2or the modified keel block produced from the mold shown in Fig.4may be substituted for the 1in.[25mm]block shown in Fig.3.
11.4When investment castings are made to this specifica-tion,the manufacturer may use test specimens cast to size incorporated in the mold with the castings or separately cast to size using the same type of mold and the same thermal
TABLE 2Minimum Thickness of Repaired Sections
editoriallyIron Pipe Size Plug,in.
Minimum Thickness Repaired
Section,in.[mm]
1⁄811⁄32[8]1⁄4
7⁄
16
[10]3⁄81⁄2[13]1⁄221⁄32[17]3⁄43⁄4[19]113⁄16[21]11⁄47⁄8[23]11⁄215⁄16[24]2
1[26]
TABLE 3Minimum Radius of Repaired Sections
Iron Pipe Size Plug,in.
Minimum Radius of Cylinder
or Cone,in.[mm]
1⁄89⁄16[15]1⁄4
11⁄16
[18]3⁄811⁄16[28]1⁄211⁄4[32]3⁄42[52]
121⁄2[64]11⁄44[104]
11⁄251⁄4[136]2
81⁄8[208]
TABLE 4Minimum Ligament Between Plugs A ,B
Nominal Plug Diameter,in.Minimum Ligament Between Plugs,in.[mm]
1⁄8
,1⁄4,3⁄81⁄2,1⁄41,11⁄411⁄2,21⁄8,1⁄4,3⁄825⁄8[67]41⁄8[105]65⁄8[169]91⁄2[242]1⁄2
,3⁄441⁄8[105]41⁄8[105]65⁄8[169]91⁄2[242]1,11⁄465⁄8[169]65⁄8[169]65⁄8[169]91⁄2[242]11⁄2,2
91⁄2[242]91⁄2
[242]
91⁄2
[242]
91⁄2
[242]
A
Based on efficiency of 80%.
B
Example:Assume three plugs are required for repair,one 1⁄8in.,one 3⁄8in.,and one 11⁄2in.The minimum distance permitted is as follows:
Ligament distance between 1⁄8and 3⁄8-in.plugs is 25⁄8in.[67mm].Ligament distance
between 1⁄8and 11⁄2-in.plugs is 91⁄2in.[242mm].Ligament distance between
3⁄8and 11⁄2-in.plugs is 91⁄2in.[242mm].
N OTE —The length of the keel block shall be 6in.[152mm]
FIG.2Keel Block for Test Coupons
conditions that are used to produce the castings.These test specimens shall be made to the dimensions shown in Fig.1of Specification A 732or Fig.5and Fig.6of Test Methods and Definitions A 370.
11.5The manufacturer shall cast a sufficient number of test coupons to provide for each ferritizing anneal.The test coupons shall be heat treated with the castings they represent.Sectioning of the test coupons prior to heat treating is not permitted.
11.6The metallographic examination shall be made on a test lug from the test coupon shown in Fig.7or from a casting;or from a representative test coupon poured with the casting(s).The test coupon shall represent the metal treated with the nodularizing agent.
12.Number of Tests and Retests
12.1One tension test shall be made from sections cut from the test coupons (Fig.5)required by Section 11.
12.1.1Unless otherwise stated in the contract or order for castings,a metallographic examination may be substituted for the tension test when separately cast test coupons are used.When the microstructure option is used,a minimum of one tension test is required from each day’s melt and for each heat treatment (see 12.2).
12.2If any tension test specimen shows obvious defects,another from the same coupon,or from another coupon/or representing the same metal and the same anneal charge,may be tested.If an apparently sound test specimen fails to conform to this specification,castings may be re-annealed,if required,and two retests made.If either retest fails to conform to this specification,the castings they represent shall be rejected.13.Tension Test Specimen Preparation
13.1The standard machined 1⁄2in.[12.5mm]round tension test specimen with 2in.[50mm]gauge length as shown in Fig.
6shall be used except where the 1⁄2in.[12.5mm]Y-block test coupon is required.In this case,either of the small size specimens,0.375or 0.250in.[9or 6.5mm]round as shown in Fig.6shall be used.
14.Test Methods
14.1Chemical analysis shall be made in accordance with Test Method E 1806.
14.2The yield strength shall be determined in accordance with Test Methods E 8using one of the following methods:14.2.1The 0.2%off-set method,or
14.2.2Extension under load method where the yield strength may be determined as the stress producing an elonga-tion under load of 0.375%;that is,0.0075in.[0.19mm]in a gauge length of 2in.[50mm].
14.3The hardness of the ductile iron as represented by the test specimens and castings shall be determined in accordance with Test Method E 10.
14.4The percentage of each graphite type shall be deter-mined by manual counting,semi-automatic or automatic image analysis methods.The sum of all graphite types shall total to 100%.
15.Records
15.1Records of the chemical composition,mechanical properties,and metallographic examination,when applicable,shall be systematically made and maintained.
16.Inspection
16.1Unless otherwise specified in the contract or purchase order,the manufacturer shall be responsible for carrying out all the tests and inspection required by this specification.
16.2The inspector representing the purchaser shall have entry at all time,while work on the contract of the purchaser is being performed,to all parts of the manufacturer’s works which concern the manufacturer of the material ordered.The manufacturer shall afford the inspector all reasonable facilities to satisfy him that the material is being furnished in accordance with these specifications.Unless otherwise specified,all tests and inspection shall be made at the place of manufacture or by an approved independent laboratory prior to shipment,and shall be so conducted as not to interfere unnecessarily with the operation of the works.
17.Certification
17.1When agreed upon in writing by the purchaser and the supplier,a certification shall be made on the basis of accep-tance of the material.This shall consist of a copy of the manufacturer’s test report or a statement by the supplier accompanied by a copy of the test results,that the material has been sampled,tested,and inspected in accordance with the provisions of this specification.Each certification so furnished shall be signed by an authorized agent of the supplier or manufacturer.
18.Product Marking
18.1Castings for valves,flanges,pipe fittings,and unions shall be marked for material identification in accordance
with
“Y’’BlockSize
Dimensions
For Castings of Thickness Less Than 1⁄2in.[13mm]
For Castings of Thickness 1⁄2in.[13mm]to 11⁄2in.[38mm]
For Castings of Thickness of 11⁄2in.[38mm]
and Over
in.[mm]
in.[mm]in.[mm]A 1⁄2
[13]1[25]
3[75]B 15⁄8[40]21⁄8[55]5[125]C 2[50]3[75]4[100]D 4[100]
6[150]
8[200]E
7[175]approx
7[175]approx
7[175]approx
FIG.3Y-Blocks for Test
Coupons
the Standard Marking System for Valves,Flanges,Pipe Fit-tings,and Unions,SP-25.Castings for gasketed mechanical couplings and fittings may be marked in accordance with F 1476or F 1548respectively.
18.2Castings,other than valves,flanges,pipe fittings,and unions shall be identified subject to agreement by the manu-facturer and the purchaser.
18.3Marking shall be in such a position as not to injure the usefulness of the
castings.
FIG.4Mold for Modified Keel
Block
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