1、MIL-c-2470727 January 1989MILITARY SPECIFICATIONCASTINGS, FERROUS, GENERAL SPECIFICATION FOR, ,. ., . . . . . . . . . . .! $. .,. , . !This specification is approved for use by all Departments and Agencies ofthe Department of Defense.1. SCOPE ,1.1 ji!coDe.This specification covers the general requir
2、ements for carbon,alloy and corrosion resisting steel castings.1,2 claficat on. Castings shall be furnished in the grades and typesspecified in the applicable detail specifications (see6.2).2. APPLICABLE DOCUMENTS2.1 Government documents.u 2.1.1 Specifications and standards. The following specificat
3、ions andstandards form a part of this document to the extent specified herein. nlesotherwise specified, the issues of these documents are those listed in the issueof the Department of Defense Index of Specifications and Standards (DoDISS) andsupplement thereto, cited in the solicitation (see 6,2).SP
4、ECIFICATIONSFEDERALQ-S-781 - Strapping, Steel, and Seals.PPP-B-621 - Boxes, Wood, Nailed and Lock-Corner.MILITARYMIL-C-3774 - Crates, Wood; Open 12,000- and 16,000-pondCapacity.MIL-H-6875 - Heat Treatment of Steel, Process for.MIL-c-16173 - Corrosion Preventive Compound, Solvent Cutback,Cold-Applica
5、tion.MIL-C-52950 - Crates, Wood, Open and Covered.(See supplement 1 for list of associated specifications. )7!,Beneficial comments (recommendations, additions, deletions) and any pertinentdata which may be of use in improving this document should be addressed to:Commander, Naval Sea Systems Command,
6、 SEA 5523, Department of the Navy,Washington, DC 20362-5101 by using the self-addressed Standardization DocumentImprovement Proposal (DD Form 1426) appearing at the end of this document or byletter. !Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- M
7、IL-c-24707 uSTANDARDSMILITARYMIL-STD-105 - Sampling Procedures and Tables for Inspection byAttributes.MIL-STD-129 - Marking for Shipment and Storage.MIL-STD-271 - Requirements for Nondestructive Testing Methods.MIL-STD-278 - Welding and Casting Standard.MIL-STD-792 - Identification Marking Requireme
8、nts for SpecialPurpose Components.(Unless otherwise indicated, copies of federal and military specificatiolsand standards are available from the Naval Publications and Forms Center (ATTN:NPODS) , 5801 Tabor Avenue, Philadelphia, PA 19120-5099.)2.1.2 Ocher Government DUblications. The following other
9、 Governmentpublication forms a part of this document to the extent specified herein. Unlessotherwise specified, the issues are those cited in the solicitation.PUBLICATIONNAVAL SEA SYSTEMS COMMAND (NAVSEA)0900-LP-O03-8000 - Surface Inspection Acceptance Standards forMetals.(Application for copies sho
10、uld be addressed to the Naval Publications andForms Center (ATTN: NPODS), 5801 Tabor Avenue, Philadelphia, pA 1920-5099”)2.2 Non-Government publications. The following documents form a part ofthis document to the extent specified herein. Unless otherwise specified, theissues of the documents which a
11、re DoD adopted are those listed in the issue ofthe DoDISS cited in the solicitation. Unless otherwise specified, the issues Ofdocuments not listed in the DoDISS are the issues of documents cited in thesolicitation (see 6.2).AMERICAN SOCIETY FOR TESTING AND TERIALS (ASTM)A 370 - Standard Test Methods
12、 and Definitions for MechanicalTesting of Steel Products. (DoD adopted)A 700 - Standard Practices for Packaging, Marking, and LoadingMethods for Steel Products for Domestic Shipment.(DoD adopted)A 703 - Standard Specification for Steel Castings, GeneralRequirements , for Pressure-Containing Parts.A
13、751 - Standard Methods, Practices, and Definitions for ChemicalAnalysis of Steel Products.A 781 - Standard Specification for Castings, Steel and A11oY,Common Requirements, for General Industrial Use.A 802 - Standard Practice for Steel Castings, Surface AcceptanceStandards, Visual Examination.u(Appli
14、cation for copies should be addressed to the American Society forTesting and Materials, 1916 Race Street, Philadelphia, pA 19103.)Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.c.2477WFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGSINDUS
15、TRY, INC. (MSS)SP-55 - Quality Standard for Steel Castings for Valves, Flangesand Fittings and Other Piping Components (Visual Method).(Application for copies should be addressed to the ManufacturersStandardization Society of the Valve and Fittings Industry, Inc., 127 parkStreet, N.E, Vienna, VA 221
16、80.)(Nongovernment standards and other publications are normally available fromthe organizations that prepare or distribute the documents. These documents alsomay be available in or through libraries or other informational services. )2.3 Order of Precedence. In the event of a conflict between the te
17、xt ofthis document and the references cited herein (except for associated detailspecifications) , the text of this document takes precedence. Nothing in thisdocument, however, supersedes applicable laws and regulations unless a specificexemption has been obtained.3. REQUIREMENTS3.1 Detail specificat
18、ions. The individual item requirements shall be asspecified herein and in accordance with the applicable detail specification. I71the event of any conflict between the requirements of this specification and thedetail specifications, the latter shall govern.3.2 First article. When specified (see 6.2)
19、, a sample shall be subjectedto first article inspection (see 6.4) in accordance with 4.3.3.2.1 Basic foundrv Draccic. The contractor shall maintain a record ofbasic foundry practices (type of melting and refining unit, molding process,basic rigging design, location of risers and chills, and so fort
20、h) used in thefirst article casting. In the event of change in the basic foundry practices inthe same or subsequent order, the contractor shall notify the contractingactivity and obtain approval of the changes. The contractor may be required toperform specific first article tests and examinations to
21、 verify that the changewill not or has not degraded casting quality (see 6.3 and appendix A).3.3 Material. Unless otherwise specified in the applicable detailspecification, the stee shall be made by open hearlthor electric furnaceprocess, with or withouti+separate refining or degassing.I I3.3.1 ecov
22、ered materials. Unless otherwise specified, all productscovered by this specification shall be new and may be fabricated using materialsproduced from recovered materials to the maximum extent practicable withoutjeopardizing the intended use. The term “recovered materials” means materialswhich have b
23、een collected or recoveredfrom solid waste and reprocessed to becomea source of raw materials. None of the above shall be interpreted to mean thatthe use of used or rebuilt products is allowed under this specification unlessotherwise specifically specified. When specificti (see 6.2), virgin material
24、sshall be required.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-247073.4 Chemical comDositio. Chemical composition for heat and productanalysis shall be in accordance with the detail specification. Product analysistolerances shall be in acco
25、rdance with ASTM A 703 or ASTM A 781, as appropriatefor the application.3.5 Heat treen . Unless otheise spqcified in the-contract or purchaseorder (see 6.2), heat treatment shall be as specified in the detail specification(see 3.1),3.5.1 Heat treatin eauipment and controls. Continuous or automatic h
26、eac-treating equipment may be employed, provided such equipment produces heat-treatedcastings that meet the requirements of this specification. For the particularloading and size range of the pieces being heat treated, the temperaturerecording equipment shall correlate with the actual temperature of
27、 the castingswithin the accuracy specified in MIL-H-6875 or any other NAVSEA approved heattreatment standards and shall be maintained and calibrated on a regular basis.The temperature of the furnace charge shall be recorded during the heating andstress relieving cycles of the heat treatment. After t
28、he charge reaches theselected temperature control setting, furnaces for the heat treatment of castingsshall maintain the temperature of the heating medium and the castings at anypoint in the working zone within plus or minus 25 degrees Fahrenheit (“F).3.6 Cleaning. Unless otherwise specified in che
29、concract or purchase OrCP-(see 6.2), heads, gates, and padding which have been added by the foundry toprovide directional solidification shall be removed, When heads, gates, andpadding are removed by gas cutting or scarfil-lg,the removal shall be performedbefore the final heat treatment and in such
30、a a75anner as to not impair thecasting. Gas cutting or scarfing shall be followed by cutting, chipping, Orgrinding operations, as necessary, to provide the contour specified by thedrawing.3.7 Internal chills and char)lets. Internal chills shall not be used exceptby authorization of the Command or ag
31、ency concerned. When either chaplets orinternal chills that remain a permanent part of the casting are used they shallbe of a composition conforming to that specified for the casting in which theyare employed.3.8 Soundness.3.8.1 Surface soundness. Castings shall be of uniform quality andcondition, v
32、isually free of cracks, burrs, sand, hard spots, tears, shrinkage,cold shuts, excessive scale, fins, porosity, and segregation to the extent thevconform to the requirements of ASTM A 802, MSS SP-55, NAVSEA 0900-LP-O03-8000 orother standard as specified (see 6.2) for surface inspection of castings.3.
33、8.2 nternal soundness. Castings shall meet the internal soundnessrequirements specified in 4.3.2 for first article inspection and in 4,6.5 forquality conformance inspection.3.9 Repair of defects. Unless otherwise specified (see 6.2), weld repail- Wshall be in accordance with MIL-STD-278. The casting
34、s shall not be peened,plugged or impregnated LO stop leaks. Defects not requiring welding may heground or chipped out provided the defective area is faired into the surroundinarea and the design thickness is not violated.4Provided by IHSNot for ResaleNo reproduction or networking permitted without l
35、icense from IHS-,-,-KIL-C-24707wI(13.10 Dimensions and tolerance. Castings shall conform to shapes,tolerances , and sizes indicated by the applicable patterns or drawings asspecified (see 6.2).3.11 Identifica tio.3.11.1 Information reauired. To provide.positiveidentification, the individual castings
36、 shall be marked(a) Foundrys name or trademark.(b) MIL-C-24707.(c) Pattern or part number.(d) Heat number.traceability andwith the following:(e) Final heat treat lot number or equivalent traceable code.3.11.2 Method and location of marking. The method of marking shall be by“cast-in marking”, low-str
37、ess die stamps, or vibroetching. The location ofmarking shall be at a low stress area as shown on the casting drawing. Whenspecified (see 6.2), marking shall be in accordance with MIL-STD-792.3.11.3 sll Castin=. Where individual castings cannot be marked inaccordance with 3.11.1 and 3.11.2, they may
38、 be bundled or boxed and each bundleor box shall be marked with a metal or oil-proof tag containing the informationspecified in 3.11.1.3.12 Mechanical and impact Properties. The minimum mechanical and impactproperties shall be in accordance with the detail specification.4. QUALITY ASSIJRANCE PROVISI
39、ONS4.1 ResDonsibiitY for inspection. Unless otherwise specified in thecontract or purchase order, the contractor is responsible for the performance ofall inspection requirements (examinations and tests) as specified herein. Exceptas otherwise specifie: in the contract or purchase order, the contract
40、or may usehis om or any oth,9r.Efacilities,suitable for the performance of the inspectionrequirements specified herein, unless disapproved by the Government. TheGovernment reserves the right ,COperform any of the inspections set forth in thespecification where such inspections are deemed necessary t
41、o ensure supplies andservices conform to prescribed requirements.4.1.1 ResDOnsibillitV fOr comDliante. All items shall meet all requirementsof sections 3 and 5. .,Theinspection set forth in this specification shall becomea part of the contractors overall inspection system or quality program. Theabse
42、nce of any inspe,lionrequirements in the specification shall not relieve thecontractor of the res.ponsibili,tyof ensuring that all products or suppliessubmitted to the GoveJgnment fo,racceptance comply with all requirements of thecontract. Sampling inspection, as part of the manufacturing operations
43、, is anacceptable practice to ascertain conformance to requirements; however, this doesnot authorize submission of know-ndefective material, either indicated or actual ,nor does it commit the Government to accept defective material.5Provided by IHSNot for ResaleNo reproduction or networking permitte
44、d without license from IHS-,-,-MIL-C-24707d4.2 Classification of inspections. The inspection requirements specifiedherein are classified as follows:(a) First article inspection (see 4.3).(b) Quality conformance inspection (see 4.4).4.3 First article insy)ection. When first article inspection is requ
45、ired(see 3.2), it shall consist of the examination and tests specified in 4.3.2,4.3.3, 4.6.1, 4.6.3, 4.6.4, and as specified in the detail specifications (see6.3 and appendix B).4.3.1 SamDlinz for first article insectio. The casting submitted forfirst article inspection shall be the first article ca
46、sting which isrepresentative of the proposed production castings. When required (see 6.2),first article sampling shall be in accordance with MIL-STD-105 and shall be basedupon the specified first article population inspection level and acceptablequality level (AQL) as specified (see 6.2).4.3,2 Fadi
47、=apo hic inspection, The first article casting or castings shallbe radiographically inspected to the acceptance criteria for the specifiedcriticality level of MIL-STD-278 or other standard as specified (see 6,2). Whznapproved by the Command or agency concerned-, other inspection methods may beemploy
48、ed.4.3.3 Mechanical and impact property tests. The first article mechanicaland impact test coupons shall be taken from the casings as specified in4.5,2.2.2. These mechanical and impact properties shall meet the minimumproperties specified in the contract or order for the designated sections of theca
49、stings and shall be related to the properties obtained from separately castcoupons of 4.5.2.2.2 prepared with the first article casting for assurance thatproduction castings meeting test coupon requirements shall have the specifiedproperties in the designated sections.4.4 Quality conformance inspection. Quality conformance inspection shallbe in accordance with 4.5 through 4.7 (see 6.3.and appendix A).4.5 Lot size. Unless otherwise specif
