specification for ferritic ductile iron ...c1p.ir/wp-content/uploads/076-asme-sec-ii-a-sa-395.pdfe...

SPECIFICATION FOR FERRITIC DUCTILE IRONPRESSURE-RETAINING CASTINGS FOR USE AT

ELEVATED TEMPERATURES

SA-395

[Identical with ASTM Specification A 395-88 (Reapproved 1993)e1.]

1. Scope

1.1 This specification covers ductile iron castings forpressure-retaining parts for use at elevated temperatures(Note 1).

1.2 Valves, flanges, pipe fittings, pumps, and otherpiping components are generally manufactured in ad-vance and supplied from stock by the manufacturer,jobber, or dealer.

1.3 For supplemental casting requirements Specifica-tion A 834 may be utilized.

1.4 The values stated within this specification arein inch/pound units. A separate Specification A 395Mis the metric companion to this specification. The textin both is identical.

NOTE 1 — For service other than as specified in this section,reference should be made to Specification A 536 for Ductile IronCastings.

2. Referenced Documents

2.1 ASTM Standards:A 247 Test Method for Evaluating the Microstructure of

Graphite in Iron CastingsA 370 Test Methods and Definitions for Mechanical Test-

ing of Steel ProductsA 395M Specification for Ferritic Ductile Iron Pressure-

Retaining Castings for Use at Elevated Temperatures(Metric)

A 536 Specification for Ductile Iron CastingsA 732/A 732M Specification for Castings, Investment,

Carbon and Low Alloy Steel for General Application,

718

and Cobalt Alloy for High Strength at Elevated Tem-peratures

A 834 Specification for Common Requirements for IronCastings for General Industrial Use

E 8 Test Methods of Tension Testing of Metallic Ma-terials

E 10 Test Method for Brinell Hardness of Metallic Ma-terials

E 30 Test Methods for Chemical Analysis of Steel, CastIron, Open-Hearth Iron, and Wrought Iron

E 59 Test Method of Sampling Steel and Iron for Determi-nation of Chemical Composition

E 186 Reference Radiographs for Heavy-Walled (2 to41⁄2-in. (51 to 114-mm)) Steel Castings

E 280 Reference Radiographs for Heavy-Walled (41⁄2 to12-in. (114 to 305-mm)) Steel Castings

E 446 Reference Radiographs for Steel Castings up to 2in. (51 mm) in Thickness

E 689 Reference Radiographs for Ductile Iron Castings

2.2 Manufacturer’s Standardization Society of theValve and Fittings Industry Standard:SP 25 (1964 edition) Standard Marking Systems for

Valves, Flanges, Pipe Fittings, and Unions

3. Ordering Information

3.1 Orders for material under this specification shallinclude the following applicable information:

3.1.1 Drawing, catalog number or part identifica-tions,

3.1.2 Quantity (weight or number of pieces),

3.1.3 ASTM designation and year of issue,

COPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling ServicesCOPYRIGHT American Society of Mechanical EngineersLicensed by Information Handling Services

PART A — FERROUS MATERIAL SPECIFICATIONS SA-395

3.1.4 Heat treating requirements (see 4.2.1),

3.1.5 Pressure test requirements (see 6.4.2),

3.1.6 Test samples from castings (see 9.1.1 and10.1.1),

3.1.7 Test coupons size (see 9.2),

3.1.8 Metallographic option (see 10.1.1),

3.1.9 Place of inspection (see 14.1),

3.1.10 Certification requirements (see 15.1),

3.1.11 Identification marking (see 16.2), and

3.1.12 Supplemental Requirements (see 1.3 andS1).

4. Materials and Manufacture

4.1 The melting method and the nodularizing practiceshall be optional with the foundry.

4.2 Except as provided in 4.2.1, all castings shallbe given a ferritizing heat treatment that producesessentially a ferritic structure that contains no massivecarbides.

4.2.1When specified in the purchase order, castingsmay be provided in an as cast condition provided theycomply with the requirements of 6.1 and 6.2.1.

4.2.2 Castings supplied in accordance with 4.2.1may be stress relieved by agreement between the manu-facturer and purchaser.

5. Chemical Requirements

5.1The casting shall conform to the following require-ments for chemical composition (Note 2):

Total carbon, min,% 3.00Silicon, max,% 2.50Phosphorus, max,% 0.08

5.1.1 The chemical analysis for total carbon shallbe made on chilled cast pencil type specimens or fromthin wafers approximately1/32 in. thick cut from testcoupons. Drillings are not reliable because of the proba-ble loss of graphite.

5.1.2 For each reduction of 0.01% below themaximum specified phosphorus content, an increase of0.08% silicon above the specified maximum will bepermitted up to a maximum of 2.75%.

719

NOTE 2 — Silicon contents above 2.75%, or phosphorus contentsabove 0.08% have a tendency to lower the impact resistance of thematerial. If the carbon content is below 3.00%, excess cementitemay form during cooling and if this is not removed during heattreatment, the impact resistance of the material may be lowered.

6. Requirements

6.1 Tensile: The ductile iron as represented by thetest specimens shall conform to the following require-ments for tensile properties:

Tensile strength, min, MPa 60 000 psiYield strength, min, MPa 40 000 psiElongation in% min,% 18

6.2 Hardness:

6.2.1 The hardness of the castings and test speci-mens shall be within the following limits:

HB, 3000 kgf load 143-187

6.3 Microstructure:

6.3.1The microstructure of the separately cast testcoupon or the casting shall be essentially ferritic andcontain no massive carbides, and have a minimum of90% Type I and Type II Graphite as in Fig. 7 or PlateI of Test Method A 247.

6.4 Pressure Test Requirements:

6.4.1Each pressure retaining casting shall be testedafter machining to the test pressure specified by theapplicable standard of ANSI, ASME Boiler and PressureVessel Code, or other pertinent code, and shall showno leaks.

6.4.2 Castings ordered under this specification notcovered by ANSI standards and ASME Pressure VesselCode, and castings for special service applications, shallbe tested to such pressures as may be agreed upon bythe manufacturer and the purchaser.

6.4.3 It is realized that the foundry may be unableto perform the hydrostatic test prior to shipment, orthat the purchaser may wish to defer testing untiladditional work or machining has been performed onthe casting. Castings ordered in the rough state forfinal machining by the purchaser may be tested hydro-statically prior to shipment by the manufacturer atpressures to be agreed upon with the purchaser. How-ever, the foundry is responsible for the satisfactoryperformance of the castings under the final hydro-static test.


SA-395 2001 SECTION II

7. Workmanship and Finish

7.1 The surface of the casting shall be examinedvisually and shall be free from adhering sand, scale,cracks, and hot tears. Any other surface discontinuitiesshall meet visual acceptance standards specified inthe order.

8. Repair

8.1 Castings for valves, flanges, pipe fittings, pumps,and other piping components ordered under applicableANSI standards shall not be repaired by plugging,welding, brazing, or impregnation.

8.2 Castings not covered in 8.1 which leak onhydrostatic tests may be repaired by plugging, providedthe following requirements are met:

8.2.1 No welding or brazing is permitted.

8.2.2 The diameter of the plug shall not exceedthe diameter of a standard 2 in. pipe plug.

8.2.3 The plugs, where practical, shall conform inall dimensions to the standard ISO3⁄8 plugs. In addition,they shall have full thread engagement correspondingto the thickness in the repaired section. Where a taperedplug is impractical because of the excess wall thicknessin terms of plug diameter and coincident thread engage-ment, other types of plugs may be used provided bothfull engagement and effective sealing against pressureare obtained. Where possible, the ends of the plugshould be ground smooth after installation to conformto the inside and outside contours of the wall of thepressure vessel or pressure part.

8.2.4The material from which the plug is manufac-tured shall conform in all respects to the materialsspecifications which apply to the pressure vessel orpressure part.

8.2.5 The area adjacent to the drilled hole shallbe examined by radiography, and shall meet the Level3 acceptance requirements of Reference RadiographsE 689 and supporting Reference Radiographs E 446,E 186, or E 280 as applicable and defined in accordancewith Reference Radiographs E 689.

8.2.6 The thickness of any repaired section inrelation to the size of the plug used shall not be lessthan that given in Table 1.

8.2.7 The minimum radius of repaired sections ofcylinders or cones in relation to the size of plug usedshall not be less than that given in Table 2.

720

8.2.8 A repaired area may consist of a maximumof three plugs with a spacing such that the ligamentsbetween adjacent plugs shall not be less than listed inTable 3. Other defective areas may also be repairedby plugging provided the minimum ligament betweenplugs in adjacent areas is not less than twice thedistance from the nearest plug, the values for whichare listed in Table 3.

8.3 Surface imperfections in castings other thanvalves, flanges, pipe fittings, pumps, and other pipingcomponents may be repaired by plugging provided thedepth of the plug is not greater than 20% of thethickness of the casting section and the diameter ofthe plug is not greater than its length. Repair of surfacedefects may not be done on pressure containing portionsof castings. The plug need not be threaded. The condi-tions of 8.2.1 and 8.2.4 shall also be satisfied.

9. Test Coupon

9.1 The separately cast test coupons from which thetension test specimen is machined shall be cast to thesize and shape shown in Fig. 1, Fig. 2, or Fig. 4.Sectioning procedure for removing test specimens fromY-blocks is shown in Fig. 3.

9.1.1Test samples may be removed from castingsat locations designated on a drawing or as agreed toby manufacturer and purchaser.

9.1.2 Test bars removed from castings shall con-form to Fig. 5. The testing diameter shall be1⁄2 in. ifpossible. Smaller diameters shall be utilized if necessary.

9.2 The test coupon size shall be as mutually agreedupon between the manufacturer and purchaser. In theabsence of agreement, it shall be the option of themanufacturer.

9.3 The test coupons shall be cast in molds madeof suitable core sand having a minimum wall thicknessof 11⁄2 in. for the 1⁄2 in., 1 in. sizes, and 3 in. for the3 in. size. The coupons shall be left in the mold untilthey have changed to a black color (approximately900°F or less). The keel block as shown in Fig. 1 orthe modified keel block produced from the mold shownin Fig. 4 may be substituted for the 1 in. block shownin Fig. 2.

9.4 When investment castings are made to this speci-fication, the manufacturer may use test specimens castto size incorporated in the mold with the castings orseparately cast to size using the same type of moldand the same thermal conditions that are used to produce



the castings. These test specimens shall be made tothe dimensions shown in Fig. 1 of Specification A 732or Figs. 5 and 6 of Test Methods and Definitions A 370.

9.5 Separately cast test coupons shall be pouredimmediately after the castings and shall represent themetal treated with the nodularizing agent, and be identi-fied with the castings they represent.

9.6 The manufacturer shall cast a sufficient numberof test coupons to provide for each ferritizing anneal.The test coupons shall be heat treated with the castingsthey represent. Sectioning of the test coupons prior toheat treating is not permitted.

9.7 The metallographic examination shall be madeon a test lug from the recommended test coupon shownin Fig. 6 or from a casting. The test coupon shallrepresent the metal treated with the nodularizing agent.

10. Number of Tests and Retests

10.1 One tension test shall be made from sectionscut from the test coupons (Fig. 3) for each ladle treatedwith the nodularizing agent.

10.1.1 Unless otherwise stated in the contract ororder for castings, a metallographic examination maybe substituted for the tension test when separately casttest coupons are used. When the microstructure optionis used, a minimum of one tension test is requiredfrom each day’s melt and for each heat treatment(see 10.2).

10.2 If any tension test specimen shows obviousdefects, another from the same coupon, or from anothercoupon representing the same metal and the same annealcharge, may be tested. If an apparently sound testspecimen fails to conform to this specification, castingsmay be re-annealed and two retests made. If eitherretest fails to conform to this specification, the castingsthey represent shall be rejected.

11. Tension Test Specimen Preparation

11.1 The standard machined1⁄2 in. round tensiontest specimen with 2 in. gauge length as shown in Fig.5 shall be used except where the1⁄2 in. Y-block testcoupon is required. In this case, either of the smallsize specimens, 0.375 or 0.250 in. round as shown inFig. 5 shall be used.

721

12. Test Methods

12.1 Chemical analysis shall be made in accordancewith the following methods: Test Methods E 59 or E 30.

12.2 The chemical composition may also be deter-mined by spectrographic methods but should a disputearise concerning the chemical composition, the methodsspecified in 12.1 shall be used as the umpire methods.

12.3The yield strength shall be determined in accord-ance with Test Methods E 8 using one of the followingmethods:

12.3.1 The 0.2% off-set method, or

12.3.2 Extension under load method where theyield strength may be determined as the stress producingan elongation under load of 0.375%; that is, 0.0075in. in a gauge length of 2 in.

12.4 The hardness of the ductile iron as representedby the test specimens and castings shall be determinedin accordance with Test Method E 10.

12.5 The percentage of each graphite type shallbe determined by manual counting, semi-automatic orautomatic image analysis methods. The sum of allgraphite types shall total to 100%.

13. Records

13.1 Records of the chemical composition, mechani-cal properties, and metallographic examination, whenapplicable, shall be systematically made and maintained.

14. Inspection

14.1 Unless otherwise specified in the contract orpurchase order, the manufacturer shall be responsiblefor carrying out all the tests and inspection requiredby this specification.

14.2 The inspector representing the purchaser shallhave entry at all times, while work on the contract ofthe purchaser is being performed, to all parts of themanufacturer’s works which concern the manufactureof the material ordered. The manufacturer shall affordthe inspector all reasonable facilities to satisfy him thatthe material is being furnished in accordance with thesespecifications. Unless otherwise specified, all tests andinspection shall be made at the place of manufactureor by an approved independent laboratory prior toshipment, and shall be so conducted as not to interfereunnecessarily with the operation of the works.



15. Certification

15.1 When agreed upon in writing by the purchaserand the supplier, a certification shall be made on thebasis of acceptance of the material. This shall consistof a copy of the manufacturer’s test report or a statementby the supplier accompanied by a copy of the testresults, that the material has been sampled, tested, andinspected in accordance with the provisions of thisspecification. Each certification so furnished shall besigned by an authorized agent of the supplier or manu-facturer.

16. Product Marking

16.1 Casting for valves, flanges, pipe fittings, andunions shall be marked for material identification in

722

accordance with paragraph 9.6 of the Standard MarkingSystem for Valves, Flanges, Pipe Fittings, and Unions,SP-25.

16.2Castings other than valves, flanges, pipe fittings,and unions shall be identified subject to agreement bythe manufacturer and the purchaser.

16.3 Marking shall be in such a position as not toinjure the usefulness of the castings.

17. Keywords

17.1 casting; ductile iron; mechanical properties;pressure-retaining; pressure test; tensile strength; tensiontesting; yield strength



FIG. 1 KEEL BLOCK FOR TEST COUPONS

FIG. 2 Y-BLOCKS FOR TEST COUPONS

723



FIG. 3 SECTIONING PROCEDURE FOR Y-BLOCKS

724



FIG. 4 MOLD FOR MODIFIED KEEL BLOCK

725



FIG. 5 STANDARD 1/2-in. ROUND TENSION TEST SPECIMEN WITH 2-in. GAGE LENGTH AND EXAMPLES OFSMALL SIZE SPECIMENS PROPORTIONAL TO THE STANDARD SPECIMEN

FIG. 6 TEST COUPONS FOR MICROSCOPICAL EXAMINATION OF DUCTILE IRON

726



FIG. 7 SUGGESTED CLASSIFICATION OF GRAPHITE FORM IN DUCTILE CAST IRON

727



TABLE 1MINIMUM THICKNESS OF REPAIRED SECTIONS

Iron Pipe Size Plug, Minimum Thickness Repairedin. Section, in.

1⁄811⁄32

1⁄47⁄16

3⁄81⁄2

1⁄221⁄32

3⁄43⁄4

1 13⁄16

11⁄47⁄8

11⁄215⁄16

2 1

TABLE 2MINIMUM RADIUS OF REPAIRED SECTIONS

Minimum Radius of CylinderIron Pipe Size Plug, in. or Cone, in.

1⁄89⁄16

1⁄411⁄16

3⁄8 11⁄161⁄2 11⁄43⁄4 21 21⁄211⁄4 411⁄2 51⁄42 81⁄8

TABLE 3MINIMUM LIGAMENT BETWEEN PLUGSA,B

Minimum Ligament Between Plugs, in.Nominal PlugDiameter, in. 1⁄8, 1⁄4, 3⁄8 1⁄2, 1⁄4 1, 11⁄4 11⁄2, 21⁄8,

1⁄4,3⁄8 25⁄8 41⁄8 65⁄8 91⁄2

1⁄2,3⁄4 41⁄8 41⁄8 65⁄8 91⁄2

1, 11⁄4 65⁄8 65⁄8 65⁄8 91⁄211⁄2, 2 91⁄2 91⁄2 91⁄2 91⁄2

A Based on efficiency of 80%.B Example: Assume three plugs are required for repair, one 1⁄8 in.,

one 3⁄8 in., and one 11⁄2 in. The minimum distance permitted is asfollows:

Ligament distance between 1⁄8 and 3⁄8 in. plugs is 25⁄8 in.Ligament distance between 1⁄8 and 11⁄2 in. plugs is 91⁄2 in.Ligament distance between 3⁄8 and 11⁄2 in. plugs is 91⁄2 in.

728



SUPPLEMENTARY REQUIREMENT

The following supplementary requirement shall not apply unless specified in thepurchase order.

S1. A microstructure test lug is to be cast attachedto the casting at the location designated on the castingdrawing. The microstructure of the test lug shall beessentially ferrite and contain no massive carbides.

729
