1、 Comments, suggestions, or questions on this document should be addressed to U.S. Army RDECOM, Tank Automotive Research, Development and Engineering Center, ATTN: RDTA-EN/STND/TRANS MS #268, 6501 E. 11 Mile Road, Warren, MI 48397-5000 or emailed to DAMI_STANDARDIZATIONconus.army.mil. Since contact i
2、nformation can change, you may want to verify the currency of this address information using the ASSIST Online database at https:/assist.daps.dla.mil. AMSC N/A FSC 2530 INCH-POUND MIL-DTL-62567D(AT) 8 April 2010 SUPERSEDING MIL-DTL-62567C(AT) 16 September 1998 DETAIL SPECIFICATION TORSION BAR, SUSPE
3、NSION This specification is approved for use by the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC), Research, Development and Engineering Command (RDECOM), Department of the Army, and is available for use by all Departments and Agencies of the Department of Defense.
4、1. SCOPE 1.1 Scope. This specification covers a military combat vehicle suspension torsion bar. 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4 or 5 of this specification. This section does not include documents cited in other sections of this
5、 specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3, 4 or 5 of this specification, whether or no
6、t they are listed. 2.2 Government documents. 2.2.1 Government documents, drawings, and publications. The following Government documents, drawings, and publications form a part of this document to the extent specified herein. Unless otherwise specified, the issues are those cited in the solicitation
7、or contract (see 6.2). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-62567D(AT) 2 U.S. ARMY TACOM DRAWINGS 12369003 - Steel Ext. Surfaces, Green 383 12292010 - Torsion Bar, Suspension 10929033 - Gage, Special Involute Go Composite Ring 1092
8、9035 - Gage, Involute Not Go Sector Ring (Copies of these documents are available from DAMI_STANDARDIZATIONconus.army.mil or U.S. Army RDECOM, Tank Automotive Research, Development and Engineering Center, ATTN: RDTA-EN/STND/TRANS MS #268, 6501 E. 11 Mile Road, Warren, MI 48397-5000.) 2.3 Non-Governm
9、ent publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract (see 6.2). ASTM INTERNATIONAL ASTM A604 - Method for Macroetch Testing of Consumable Electr
10、ode Remelted Steel Bars and Billets (DoD Adopted) ASTM E1444 - Standard Practice for Magnetic Particle Examination (Copies of these documents are available from www.astm.org or ASTM International, P.O. Box C700, West Conshohocken, PA 19428-2959.) SAE INTERNATIONAL SAE AMS 2300 - Steel Cleanliness, P
11、remium Aircraft - Quality Magnetic Particle Inspection Procedure (DoD Adopted) SAE AMS 6257 - Steel Bars, Forgings, and Tubings (DoD Adopted) SAE AMS-STD-2154 - Inspection, Ultrasonic, Wrought Metals, Process for (Copies of these documents are available from www.sae.org or SAE Customer Service, 400
12、Commonwealth Drive, Warrendale, PA 15096-0001.) 2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supe
13、rsedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), a sample shall be subjected to first article inspection in accordance with 4.4 (see 6.3). Provided by IHSNot for ResaleNo reproduction or networking perm
14、itted without license from IHS-,-,-MIL-DTL-62567D(AT) 3 3.2 Design and construction. 3.2.1 Materials. The contractor shall select the material, but the material shall be capable of meeting the operational requirements specified herein. It is recommended, but not mandatory, that steel alloy 300M, cla
15、ss 3, condition optional, as specified in SAE AMS 6257 be used. 3.2.1.1 Billet material. The billet material shall meet both of the following requirements: a. The billet material shall have a sufficient internal cleanliness as determined by testing in accordance with 4.2a. b. The billet material sha
16、ll have a sufficient surface cleanliness as determined by testing in accordance with 4.2b. 3.2.1.2 Bar stock. The bar stock shall meet both of the following requirements: a. The finished bar stock (before hot upsetting) shall have a sufficient internal cleanliness as determined by testing in accorda
17、nce with 4.2c. b. The finished bar stock shall be as follows: 1. The finished bar stock (before hot upsetting) shall have a sufficient surface cleanliness as determined by testing in accordance with 4.2d. No laps or seams shall be permitted, or, 2. The finished bar stock shall have a sufficient inte
18、rnal cleanliness as determined by testing in accordance with 4.2e. 3.2.2 Processing. 3.2.2.1 Heat treatment. The torsion bar shall be quenched and double tempered to a through hardness of Rockwell C51 minimum. This hardness is required for the bar to be compatible with the design requirements of int
19、erfacing components (see 4.6.1). 3.2.2.1.1 Decarburization and retained austenite. Microscopic examination of a prepared cross section of the torsion bar following final heat treatment at a magnification of 250 diameters shall show no evidence of retained austenite or partial decarburization beyond
20、a depth of 0.003 inches from the surface. Partial decarburization between the surface and a depth of 0.003 inches shall not result in a hardness reduction of more than 3 points Rockwell C as determined by microhardness traverse comparison between that area and the core hardness (see 4.6.1). 3.2.2.2
21、Surface indications. Magnetic particle inspection of the finished torsion bar (after final heat treatment) shall disclose no indications in excess of the requirements of SAE AMS 2300 and SAE AMS 6257. Laps, inclusions, and seams shall not be permitted. Nicks and scratches less than four inches long
22、shall be removed by blending the surface to a depth of not greater than 0.010 inch. After removal of scratches, the torsion bar shall still meet dimensional requirements of Drawing 12292010 (see 4.6.2 and 4.6.3). Provided by IHSNot for ResaleNo reproduction or networking permitted without license fr
23、om IHS-,-,-MIL-DTL-62567D(AT) 4 3.2.2.3 Surface finish. The surface texture of a torsion bar shall be as specified on Drawing 12292010 (see 4.6.3). 3.2.2.4 Preset. The torsion bar shall be preset to the requirements of Drawing 12292010 by twisting one end of the bar in the direction indicated a mini
24、mum of three times while restraining the opposite end. The bar shall be held stationary at full windup for not less than 10 seconds during each preset cycle. The last twist shall result in a change of set angle of not greater than 1.0 degree from the preceding twist. The degrees of permanent set sha
25、ll be not greater than the amount specified on Drawing 12292010 (see 4.6.4). 3.2.2.5 Straightness. Straightness of the torsion bar body shall be controlled as specified on Drawing 12292010. Stock or bars may be straightened at any time during the machining sequence as required to meet the drawing re
26、quirements for as-machined straightness prior to any cold working. Note that the drawing straightness control for as-machined torsion bars is tighter than the final straightness requirement. Bars shall be straightened at a temperature below the tempering temperature. Care shall be exercised to avoid
27、 damage to the surface of the bar during the straightening operation. 3.2.3 Surface protection. 3.2.3.1 Cleaning. Prior to the application of any protective coating, bars shall be cleaned in accordance with Drawing 12369003, method I or method II, with no film thickness specified. 3.2.3.2 Priming. T
28、he body of the torsion bar shall be primed with primer coating conforming to Drawing 12369003 with no film thickness specified. 3.2.3.3 Protective covering. A protective covering shall be applied to the body of the bar in the area shown on Drawing 12292010. This covering shall prevent damage from ha
29、ndling or shipping such as scratches, nicks or abrasions (see 6.6). 3.2.4 Dimensions. Dimensions and tolerances of the torsion bar shall be as specified on Drawing 12292010. 3.2.5 Endurance. The torsion bar shall demonstrate a minimum life of 45,000 cycles and an average life of 80,000 cycles with a
30、n angular creep of not greater than 4 degrees and torsional deflection as specified in table I (see 4.6.5). TABLE I. Endurance. Part number 12292010 Torsional deflection (degrees) -1, -2 12-71 -7, -8 12-69 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-
31、,-,-MIL-DTL-62567D(AT) 5 3.3 Product marking. The part identification number, mill heat marking, preset arrow and manufacturers identification shall be applied to the ends of the torsion bar as specified on Drawing 12292010. 3.4 Workmanship. The torsion bar shall be free of defects such as scratches
32、, nicks, tool marks, burrs, sharp edges, scratched finish, peeled or blistered primer, or improperly applied protective covering (see 4.6.3). 4. VERIFICATION 4.1 Classification of inspections. The inspection requirements specified herein are classified as follows: a. First article inspection (see 4.
33、4). b. Conformance inspection (see 4.5). 4.2 Materials discontinuities and flaws. Materials shall be free of discontinuities and flaws that will affect torsion bar function and, as a minimum, the materials shall pass the following tests: a. To determine conformance with 3.2.1.1a, all billet material
34、s shall pass the ultrasonic test requirements of SAE AMS-STD-2154, type I or II, class A. b. To determine conformance with 3.2.1.1b, all billet materials shall be macroetched in accordance with ASTM A604 at each crop location. The macrostructures shall be equal to or better than severity A for class
35、 1 or 2 and severity B for class 3 and 4. c. To determine conformance to 3.2.1.2a, all finished bar stock shall pass the ultrasonic test requirements of SAE AMS-STD-2154, type I or II, class AA. d. To determine conformance with 3.2.1.2.b.1, all finished bar stock shall pass 100 percent magnetic part
36、icle inspection using the fluorescent wet continuous method in accordance with ASTM E1444, except waive the frequency and severity requirements as specified in SAE AMS 2300. e. To determine conformance to 3.2.1.2.b.2, all finished bar stock shall pass the ultrasonic test requirements of SAE AMS-STD-
37、2154, type I or II by the Shear Wave (Angle Beam) Technique. Equipment calibration shall be performed using a cylindrical specimen of the same diameter and surface finish as the finished product containing a groove not greater than 0.004 inches deep by 4 inches long, oriented in the longitudinal dir
38、ection of the bar. Actual dimensions of the notch shall be measured and marked on the cylindrical specimen. 4.2.1 Billet material properties. If required by the Government (see 6.2), the contractor shall provide a sample of the billet material from each mill heat crop location for verification of ma
39、terial properties. The sample shall be produced using the suppliers standard manufacturing practices. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-62567D(AT) 6 4.3 Inspection conditions. Unless otherwise specified (see 6.2), all inspection
40、s shall be conducted under the following standard (room) ambient conditions: a. Temperature: 7718 degrees Fahrenheit (F) b. Relative humidity: Uncontrolled room ambient c. Atmospheric pressure: Site pressure 4.4 First article inspection. 4.4.1 Sample size. Six torsion bars of the 12292010-1 configur
41、ation shall be subjected to first article inspection. 4.4.2 Inspection routine. The first article samples shall be subjected to the group A, B, C and D inspections below, except that the 100,000 cycle minimum of 4.5.2 shall not apply. 4.4.3 Failure. Failure to pass group A, B and C inspections shall
42、 be cause for refusal to grant first article approval. Each torsion bar subjected to group D inspection shall demonstrate a minimum life of 45,000 cycles. Average life calculation of 80,000 cycles will be based on the total number of endurance cycles accumulated during testing divided by the total n
43、umber of torsion bars tested. If a torsion bar exhibits endurance life of 200,000 cycles or more prior to failure, its life shall be taken as 200,000 cycles for the average life calculation. Failure to meet group D minimum life or average life requirements shall be cause for refusal to grant first a
44、rticle approval. 4.4.4 Disposition of samples. Samples which have been subjected to first article inspection shall not be delivered as new equipment under the contract. 4.5 Conformance inspection. 4.5.1 Inspection of product for delivery. Inspection of product for delivery shall consist of group A,
45、B and C inspections. 4.5.1.1 Inspection lot. Unless otherwise noted, an inspection lot shall consist of all torsion bars produced under essentially the same conditions and offered for inspection at one time. The lot may include a mixture of the torsion bar configurations specified on Drawing 1229201
46、0. Sufficient quantities of 12292010-1 configuration shall be fabricated to verify conformance to 4.4.1. 4.5.1.2 Group A inspection. Group A inspection shall consist of the inspections specified in table II. 4.5.1.2.1 Group A sampling. 100 percent inspection shall apply unless an approved statistica
47、l process control (SPC) plan is used (see 6.4.2). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-62567D(AT) 7 4.5.1.2.2 Group A failure. The supplier may rework a rejected torsion bar to correct the defect(s) and resubmit it for inspection.
48、Rework shall be within the confines of drawing and specification requirements. 4.5.1.3 Group B inspection. Group B inspection shall consist of the inspections specified in table III. TABLE II. Group A inspection. Inspection Requirement Inspection method Surface indications 3.2.2.2 4.6.2 Surface fini
49、sh 3.2.2.3 4.6.3 Workmanship 3.4 Visual Spline major diameter 3.2.4 Go Ring Gage and Not Go Ring Gage External involute spline 3.2.4 Special Involute Go Composite Ring Gage 10929033 and Involute Not Go Sector Ring Gage 10929035 4.5.1.3.1 Group B sampling. Frequency of inspection and/or any special arrangements for establishing the frequency of inspection shall be as specified in the contract or purchase order (see 6
