1、MIL-C-48147 (MU) 18 April 1973 SUPERSEDING 8 June 1966 PA-PD-2870 MILITARY SPECIFICATION CASTINGS, FERRITIC MALLEABLE IRON FOR M151 WARHEAD I. SCOPE 1.1 This specification covers one grade of ferritic malleable iron castings for ammunition components. 2 APPLICABLE DOCUMENTS 2.1 The following documep
2、ts of the issue in effect on date of invitation for bids or request for proposal, form a part of the specification to the extent specified herein. SPECIFICATIONS MILITARY MIL-A-2550 - Ammunition and Special Weapons, General Specification For. STANDARDS mDERAL Federal Test Method Standard No. 151 MIL
3、ITARY MIL-STD-109 Definitions MIC-STD-1168 - Lot numbering of Ammunition. MIL-STD-1169 - Packaging, Packing and Marking for Shipment of Inert Ammunition Components. - Quality Assurance Terms and FSC: i340 *% THIS DOWMENT CONTlttMS -2. PAGES. b Provided by IHSNot for ResaleNo reproduction or networki
4、ng permitted without license from IHS-,-,-MIL-C-48147 (MU) (Copies of specifications, stanards, drawings and publications required by suppliers in connection with specific procurement functions should be obtained from the procuringactivity or as directed by the Contracting Officer). 3. REQUIREMl3NTS
5、 3.1 Melting Process,-The iron shall be made by one of the following processes: air-furnace, open hearth, electric-furnace or any of the multiplex processes. or automatic molding equipment. 3.2 Molding,-Molds and cores shall be made on semi-automatic 3.3 Heat Treatment.-Castings shall be annealed in
6、 a con- Heat treatment shall be performed trolled atmosphere furnace , on the whole casting in such a manner as to result in uniform mechanical properties throughout the individual part and through- out the heat treat lot, 3 , 3.1 After Heat Treatment .-After heat treatment , heating of the castings
7、 above the second stage annealing temperature shall not be permitted. -2 3.4 Mechanical Properties,-The castings shall meet the mechanical property requirements shown in Table I, TABLE I Yield Strength (psi) Minimum (0.2 percent Tensile Strength Elongation Brinell* offset) Minimum (psi) Minimum (XI
8、Hardness 28,000 48,000 10 110 to 156 *Brinell hardness range is advisory only, foundry control approved by the procuring activity, 3.5 Foundry Control.-Castings shall be produced under 3.6 Soundness.-The soundness of caotings shall meet standards furnished or approved by the procuring aotivity using
9、 inspection methods specified Ln the item specification and by the procuring activity, 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-48147 (MU) 3.7 Repair of Castings .-Defective castings shall not be plugged or welded. 3.8 Mottle.-Castinps
10、 shall be free of mottle (primary graphite) when tested in accordance with 4.4.3. 3.9 Identification of Castings ,-Castings representing a heat treat lot shall be identified in a manner approved by the procurfng activity. 4, QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection,-Unless othe
11、rwise speci- fed in the contract or purchase order, the supplier is responsible for the performance of all inspection requirements as specified herein. Except as otherwise specified in the contract or order, the supplier may use his own or any other facilities suitable for the performance of the ins
12、pection requirements specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in the speci- fication where such insQections are deemed necessary to assure supplies and services conform to prescribed requirements Re- ference
13、 shall be made to MTL-STD-103 to define terms used herein. The provisions of YIL-A-2550 shall apply, Submission of Product.-At the time each completed lot of items deliverable under the contract is submitted to the Govern- ment for acceptance, the contractor shall supply the following in- formation
14、accompanied by a certificate which attests that the in- formation provided .is correct and applicable to the product being submitted : a. A statement that the lot complies with all of the quality assurance provisions specified in this specification. b. Drawing and specification number and date, toge
15、ther with identification and date of changes thereto. c. A statement that all material purchased by the con- tractor meets requirements, when such material is controlled by Government or commercial specifications referenced in any of the contractual documents, and that certificates of conformance ar
16、e on file and available for review. The certificate shall be signed by a responsible agent of the Cer-: fifying organization. The initial certificate submitted shall be substantiated by evidence of the agents authority to bind his principal. Substantiation of the agents authority will not be 4.1.1 d
17、, Number of items in the lot. e. Date submitted, 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-Ce48147 (MU) required with subsequent certificates unless, during the course of the contract, this authority is vested in another agent of the cert
18、ifying organization, 4.2 Inspection Provisions for Production. 4.2.1 Lot Formation,-The term “inspection lot“ as used in this specification, is defined as an essentially homogeneous collection of units or products from which a representative sample is drawn and inspected to determine conformance wit
19、h applicable requirements. The sample selected shall represent only that quantity of units from which the sample was drawn and shall not be construed to represent any prior or subsequent quantities for inspection. Homogeneity shall be considered to exist provided the inspection lot has been produced
20、 by one manufacturer, in one un- changed process, in accordance with the same drawing, same draw- ing revision, same specification and same specification revision and complies with the provisions for submission of product as speoified in MIL-STD-105, Changes to the process, specification or drawing
21、not affecting safety, performance, interchangeability, or storage, as determined by the Government, shall not be deemed to alter the homogeneity of the inspection lot. All material sub- mitted for inspection in accordance with this specification shall comply with the homogeneity criteria specified h
22、erein regardless of the type of sampling procedure which is being applied to deter- mine conformance with requirements, Lot numbering, as required, shall be in accardance with MIL-STD-1168. Each inspection lot shall bear a unique lot number, 4 Provided by IHSNot for ResaleNo reproduction or networki
23、ng permitted without license from IHS-,-,-4.2.2 Heat-treatment Lot.-To determine cornpliance with the mechanical properties, 3.4, any quantity of castings not to exceed four (4) hours production of the final heat-treatment in the same furnace, for the same length of time or at the same conveyor spee
24、d, shall be considered as a heat-treatment lot. If a batch type heat treat furnace is used, any quantity of 5,000 castings or less shall be considered a heat-treatment lot. The lot th.us constituted shall be the basis for selection of sample castings to be used for“ tension tests, 4.3.1.2. 4.3 Testi
25、ng 4.3.1 Mechanical Properties 4.3:l.i Hardness,-In order to insure uniformity of heat- treatment and to establish a hardness range, to assure compliance with specified mechanical properties each casting after final heat-treatment shall be subjected to a hardness test with a Brinell Hardness Tester
26、at a location on the casting specified or approved by the procuring agency. . 4.3.1.1.1 Alternate hardness testing.-A direct reading Brinell Hardness Testing-Machine may be substituted for the Brinelloscope method, provided the same diameter ball is used and-the same load is applied as is used in St
27、andard Brinell testing, and provided that at least. 2000 castings are tested by both methods to establish a correlation between the two methods. After a correlation has been established, the dia- meter of the indentation in every tenth casting shall be measured with the Brinelloscope to assure conti
28、nued correlation. Tension Test.-Two castings from each lot repre- senting the hardest and softest castings as determined by the hardness test outlined in 4.3.1.1 or 4.3.1.1.1 shall be subjected to the tension test. One specimen from each casting sha1.l be prepared as specified in 4.4.1.2 and tested.
29、 comply with the requirements of 3.4, the hardness rangefor the lot will be established. Failure of one or more tension test specimens to comply with the requirements shall be cause for rejection of the lot represented by the specimen, 4.3.1.2 If all specimens F- a 5 Provided by IHSNot for ResaleNo
30、reproduction or networking permitted without license from IHS-,-,-MIL-C-48147 (MU) 4.3.1.3 Retest.-When one or more tension test specimens fail to comply with the requirements of 3.4 and do not qualify for retest under 4.4.1.2.3, a new hardness range shall be established. The rejected lot may at the
31、 direction of the contractor, be reheat-treated prior to establishing a new hardness range. The tension test, in compliance with 4.3.1.2 shall be conducted to determine the acceptability of the new hardness range. When the hardness range has been established, all castings whose values fall outside t
32、his range shall be rejected. 4.3.2 with 4.4.2 or as prescribed by the procuring activity. 4.3.3 Soundness.-Each casting shall be tested in accordance Mottle.-A minimum of two castings selected for every thirty minutes or fraction thereof of continuous pouring kirne shall be tested in accordance with
33、 4.4.3. Failure of any sample to comply with 3.8 shall be cause for rejection of all castings poured since the last acceptable sample was taken. 4.4 Test Methods and Procedures 4.4.1 Mechanical Properties 4.4.1.1 Hardness.-The Brinell hardness test shall be performed in accordance with procedures pr
34、escribed in Federal Test Method Standard No. 151. Due to the nature of the micro- structure of ferritic malleable iron, indenter balls of less than ten millimeter diametershall not be used. 4.4.1.2 Tension Test.-From each sample selected in accord- ance with 4.3.1.2, a tension test specimen shall be
35、 taken longi- tudinally from each sample, or as prescribed by the procuring activity. 4.4.1.2.1 Tension test specimen.-The specimen shall be the largest obtainable standard round specimen prescribed by Federal Test Method Standard No. 151 (type R1 thru R5) which the size of the casting and location
36、of the specimen will permit. If the size or geometry of the casting does not permit a standard round specimen, a specimen as specified or approved by the procuring activity shall be used. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I MIL-C-48147
37、13 7777706 0316724 5 E MIL-C-48147 (MU) 4.4.1.2.2 Yield strength, tensile strength, and elongation.- Yield strength shall be determined by the offset method as defined in Federal Test Method Standard No. 151. The offset shall be 0.2 percent (0.002 inches per inch of gage length). Tensile strength an
38、d elongation on each specimen shall be determined by utilizing the criteria for these tests prescribed by Federal Test Method Standard No. 151. 4.4.1.2.3 Replacement test specimens.-If a tension test specimen fails to meet the requirements of 3.4 due to an identi- fiable defect in the tensile specim
39、en which is acceptable under provisions of 3.6 and 4.3.2 or due to the fracture occuring under those conditions allowing for retests for elongation in Federal Test Method Standard No. 151, another specimen shall be machined from the same casting and tested. In the instance of failure due to an accep
40、table metal defect only one replacement specimen shall be permitted and failure of the replacement specimen to comply with the requirements of 3.4 shall be cause for rejection of the represented lot. original and replacement tests, shall be recorded and specimens which failed to meet the requirement
41、s due to the above conditions shall be identified and retained by the contractor and made available to the procuring activity for examination upon request. i Results of all tests, 4.4,2 Soundness.-When specified by the procuring agency, . castings will be inspected by ultrasonics, or if the geometry
42、 of the casting does not permit the use of ultrasonics, some form of radiography and Magnaglo, if approved by the procuring activity. Inspection Methods for less clzitical components shall be as specified by the procuring activity. shall be broken-in such a manner that the fracture will extend throu
43、gh the heaviest section. The fracture shall be visually examined for compliance with 3.8. 4.4.3 Mottle,-The samples selected in accordance with 4i3.3 K? P Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-48147 (MU) 5. PREPARATION FOR SHIPMENT 5.
44、1 Packing 5.1.1 Level C.-Castings shall be packed in accordance with the requirements of Specification MIL-STD-1169. 5.2 Labeling and Marking.-Labeling and marking shall be in accord.ance with the requirements of Specification MIL-STD-1169. 6. NOTES 6.1 Ordering Data.-Procurement documents shall spe
45、cify the following: a. Title, number and date of this specification. b. Soundness (see 3.6). Custodian: Army - MU Preparing Activity: Army - MU Project Number : 1340-A-385 *V.S. GOVERNMENT PRINTING OFFICE: 1973-714-545/5492 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
