1、MIL-L-81 558 26 September 1967 MILITARY SPECIFICATION LUG, SUSPENSION, (1000 POUND) AIRBORNE EQUIPMENT This specification is mandatory for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 This specification covers the requirements for a lug far airborne equipment. pound
2、 suspension 2. APPLICABLE DOCUMENTS 2.1 Government documents normally furnished - The following documents, 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 Federal PPP-B-585 PPP-B-591 Box, W
3、ood, Wir ebound Box, Fiberboard, Wood-cleated PPP-B-601 Box, Wood, Cleated-Plywood PPP-B-636 Box, Fiberboard P PP-B- 6 76 Box, Setup PPP-T-60 PPP-T- 76 Militaq Tape, Pres sur e-s ensitive Adhesive, Waterproof, For Packaging Tape Pressure Sensitive, Adhesive Paper, Water Resistant, For Carton Sealing
4、 MIL-P-116 Preservation, Methods of MIL-1-6 86 8 Inspection Process, Magnetic Particle I THIS DOCUMENT CONTAINS (0 PAGES. h Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-L-L55 13 = 7777706 0357bL5 b M MIL-L-81558 S PE CI FI CA TIONS Militar y
5、(C ont Id) MIL-F-7190 Forgings, Steel, For Aircraft and Special Ordnance Applications STANDARDS Federal FED-STD-151 Metals, Test Methods Military MIL-STD-129 Marking for Shipment anL Storage MS3314 Lug; Suspension, (1000 Lb. Class), Airborne Equipment PUBLICATIONS National Bureau of Standards Handbo
6、ok H28 Screw-Thread Standards for Federal Services (When requesting applicable documents, refer to both title and number. Copies of unclassified documents may be obtained from the Commanding Officer, Naval Supply Depot (Code 1051), 5801 Tabor Avenue, Philadelphia, Pennsylvania 19120. Requests for co
7、pies of classified documents should be addressed to the Naval Supply Depot, via the cognizant Government inspector .) 3. REQUIREMENTS 3.1 Preproduction - The suspension lug furnished under this specification shall be a product which has been inspected and passed the preproduction inspection specifie
8、d herein. 3.2 Materials - Materials shall conform to applicable specifications and shall be as specified herein and .on applicable drawings. 3.3 Design and construction - The design and construction of the suspension lug shall be as specified herein and in accordance with MS3314. r 4 2 Provided by I
9、HSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-L558 33 W 7797706 0357636 MIL-L-81558 3.3.1 Forging - The suspension lugs shall be constructed from forgings in accordance with MIL-F-7190, Grade B. 3.3.2 Threads - Thread dimensions and designations shall be
10、interpreted in accordance with Handbook H28. 3.4 Performance - The suspension lug shall meet the performance requirements specified in Section 4 when subjected to the applicable inspections. 3.5 Hardness - The suspension lug shall meet the hardness requirement indicaed on MS3314. 3.6 Magnetic partic
11、le hspection - The suspension lugs furnished under this specification shall pass the magnetic particle inspection specified in Section 4. 3.7 Worlunanship - The workmanship displayed in fabrication of the suspension lug shall be such as to assure, within design limitations, ability of the suspension
12、 lug to meet its performance requirements under all applicable environmental conditions. Unauthorized repair, welding, heavy burrs, are typical signs of inferior workmanship. The standards of workmanship exhibited in any approved preproduction sample, subject to any qualification stated in the Gover
13、nments notice of approval, shall be determinative of the requirements of the contract relative to workmanship insofar as not specifically covered by applicable specifications. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection - Unless otherwise specified in the contract or purchase o
14、rder, the suppier is responsible for the performance of all inspection requirements as specified herein. Except as otherwise specified, the supplier may utilize his own facilities or any commercial laboratory acceptable to the Gavernment. The Government reserves the right to perform any of the in- s
15、pections set forth in he specification where such inspections are deemed necessary to assure supplies and services conform to prescribed requirements. 4 -2 Classification of inspection - The inspection of the suspension lugs shall be classified as follows: (a) Preproduction inspection (b) Quality co
16、nformance inspection 4*3 Preproduction inspection - Preproduction inspection shall consist of all the inspections of this specification conducted in accordance with the inspection schedule listed below: (a) Each suspension lug shall be subjected to the following tests: Provided by IHSNot for ResaleN
17、o reproduction or networking permitted without license from IHS-,-,-MIL-L-BLSS 13 m 9999906 0357617 T m MIL-L-81558 (1 ) Examination of product (4.6 .i) (2) Hardness test (4.6.4) (3 ) Magnetic particle inspection (4.6.6) (b) Having passed the inspections in 4.3(a) the preproducl,m sample shall be di
18、vided into six (6) groups of 25 each. Each group shall be subjected to one of the following tests: (1)Tensile test (4.6.2 (c) ) Group 1 (25 lugs) (2) Tensile test (4.6.2 (d) ) Group 2 (25 lugs) (3)TensiZe test (4.6.2 (a) ) Group 3 (25 lugs) (4)Tensile test (4.6.2 (b) ) Group 4 (25 lugs) (5)Tensile t
19、est (4.6.2 (e) ). Group 5 (25 lugs) (6) Impact test (4.6.3) Group 6 (25 lugs) 4.3.1 Sampling for preproduction inspection - Unless otherwise specified, as soon as practicable after award of contract or order, the contractor shall furnish preproduction samples for inspection to determine conformance
20、with this specification and MS3314. Preproduction samples shall consist of one hundred fifty (150) suspension lugs. The samples shall be identified with the manufacturers part number and contract number and shall be inspected as specified herein and in accordance with the contract or order (see 6.2)
21、. 4.4 Quality conformance inspection - The quality conformance inspection shall consist of individual inspection and sampling tests. 4.4.1 Individual inspection - Unless otherwise specified each suspension lug on the contract or order shall be subjected to the following inspection in the order liste
22、d. Any lug containing a defect or failing to pass any of these inspections shall be rejected: (a) Examination of product (4.6 .l) (b) Hardness test (4.6.4) (c) Proof load (4.6.5) (d) Magnetic particle test (4.6.6) Provided by IHSNot for ResaleNo reproduction or networking permitted without license f
23、rom IHS-,-,-MIL-L-81558 13 = 999990b 0359618 1 MIL-L-81558 4.4.2 Sampling inspection - A random sample of 150 suspension lugs shall be selected from each production lot and shall be subjected to the following tests in the order listed. Failure of any suspension lug shall be cause for rejection of th
24、e entire lot. (a) Tensile test (4.6.2 (c) ) Group 1 (25 lugs) (b) Tensile test (4.6.2 (d) ) Group 2 (25 lugs) (c) Tensile test (4.6.2 (a) ) Group 3 (25 lugs) (d) Tensile test (4.6.2 (b) ) Group 4 (25 lugs) (e) Tensile test (4.6.2 (e) ) Group 5 (25 lugs) (f) Impact test (4.6.3) Group 6 (25 lugs) 4.4.
25、2.1 Production lot - A production lot shall consist of 2000 suspension lugs heat treated at one time in one furnace and which are all subjected to the same treatment operations. If a continuous heat treating operation is employed, a lot will be defined as a quantity of 2000 lugs from a continuous ru
26、n through one furnace or treating process under one set of unchanged conditions. 4.5 Test fixture - The test fixture shall be designed to simulate a bomb rack hook having a bearing surface 13/32 inch in width. The length of thread engagement between the suspension lug and the test fixture shall not
27、exceed 1/2 inch. The thread in the fixture shall meet the following special conditions: (a) Pitch diameter 1.701 3 (min) (b) Minor diameter 1.6696 (min) 4.6 Inspection methods - 4.6.1 Examination - Each suspension lug shall be thoroughly examined to determine conformance to all of the requirements o
28、f the specification and applicable military standard for which no specific tests are described. 4.6.1.1 The suspension lugs shall be examined to ascertain that the preparation for delivery conforms to this specification. Provided by IHSNot for ResaleNo reproduction or networking permitted without li
29、cense from IHS-,-,-MIL-L-1558 13 999990b 0359639 3 MIL-L-81558 4.6.2 Tensile tests - Tensile loads shall be applied using the test fixture described in 4.5 and in the directions as shown in Figure 1. Tensile loads (a) thru (e) shall be applied at ambient room temperature and the speed of testing sha
30、ll be in accordance with Federal Test Method Standard No. 151, method 211.1, paragraph 5.4 and the load shall be held for a period of one (1) minute as follows: (a) Load, direction riWfl, 27000 lbs. There shall be no permanent deformation. (b) Load, direction “Wfi, 35000 lbs. There shall be no ruptu
31、re. (c) Load, direction “X“, 18000 lbs. There shall be no permanent deformation. (d) Load, direction “Xtf, 23300 lbs. There shall be no rupture. (e) Load, direction IiYri. Each suspension lug shall be sufficiently ductile to withstand a deflection of 0.1 inch measured at the center of the cross bar
32、in direction ffYfi without rupture when mounted in the test fixture. 4.6.3 Impact test - The finished suspension lug, notched as shown in Figure 1, maintained in a uniform temperature of -65F, shall be subjected to an impact load of 200 ft lbs applied in direction as shown in Figure 1. The impact lo
33、ad shall be produced by a body weighing 20 lbs falling freely through a distance of 10 feet. The impact shall be applied by an anvil having a flat surface 1/4 inch in diameter and a minimum hardness of Rockwell C 60. There shall be no failure. 4.6.4 Hardness test - Each suspension lug shall be subje
34、cted to the ,hardness test in accordance with FED-STD-151, Method 243.1. The hardness shall be as indicated on MS3314. 4.6.5 Proof load - Each suspension lug shall be subjected to the tensile test in 4.6.2 (a) except the load shall be held for a period of five (5) seconds. 4.6.6 Magnetic particle in
35、spection - Each suspension lug shall be inspected in accordance with MIL-1-6868. There shall be no evidence of cracks, seams, laps, or other detrimental defects, 5. PREPARATION FOR DELIVERY 5.1 5.1.1 Packaging - Packaging shall be Level A or C, as specified. Level A - Suspension lugs shall be unit p
36、ackaged, one each, in accordance with Method 1 C of MIL-P-116. The threads shall be adequately protected in the process. Preservative compound is not required. .: : 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4 MIL-L-BL558 13 W 7777906 0357620
37、T W MIL-L-81558 e079 f 003 DIA THRU 7 L MAX 16 DETAIL - IMPACT NOTCH w . &, CROSS BAR VIEW OF LOAD APPLICATION ,- FIGURE 1 Y 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-L55 13 9999906 0359623 3 W MIL-L-81558 5.1.1.1 Intermediate packaging
38、 - The intermediate package shall not weigh more than 25 pounds. The container shall conform to PPP-B-676 except when packed in wirebound boxes (See 5.2 .i). When packed in wirebound boxes, weather resistant classes of fiberboard boxes per PPP-B-636 shall be used. The center seam, side seams and man
39、ufacturers joint shall be sealed with tape conforming to PPP-T-60 or PPP-T-76. 5.1.2 Level C - Suspension lugs shall be packaged in a manner which will afford adequate protection from physical damage during shipment from the supply source to the first receiving activity for immediate use. This level
40、, as a minimum, will conform to applicable carrier rules and regulatioiis and may be the suppliers commercial practice when such meets the requirements of this level. 5.2 Packing - Packing shall be A, B or C as specified. 5.2.1 Level A - Suspension lugs, packaged as specified above, shall be packed
41、in containers conforming to the overseas requirements of PPP-B-585, PPP-B-591, PPP-B-601 or weather resistant classes PPP-B-636. Closure shall be in accordance with the closure requirements of the applicable box specifications. PPP-B-591 and PPP-B-636 are not to be used for South East Asia (SEA) shi
42、pments. 5.2.2 Level B - Suspension lugs, packaged as specified above, shall be packed in containers conforming to the domestic requirements of PPP-B-585, PPP-B-591, PPP-B-601 or PPP-B-636. Closure shall be in accordance with the closure requirements of the applicable box specifications. 5.2.3 Level
43、C - Suspension lugs shall be packed in a manner which will provide protection from corrosion, deterioration and damage during direct shipment from the contractor or supply source to the first receiving activity for immediate use. The type of containers used shall conform to applicable carrier rules
44、and regulations. 5.3 Marking - In addition to any special marking required by the contract or order, all marking shall be in accordance with MIL-STD-129. 6. NOTES 6.1 Intended use - The suspension lug covered by this specification is intended for use to support airborne equipment from aircraft suspe
45、nsion racks with 14 inch centers. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-81558 6.2 Information for contracting officer - Contracts or orders should specify the following: (a Title, number, and date of this specification. (b) Selection
46、of applicable levels of preservation, packaging, and . packing required. (c) Samples subjected to sampling inspection (see 4.4.2) are not to be considered or shipped as part of the contract or order. (d) Items of data required (see 6.3). (e) Inspection equipment (see 6.4). 6.2 .I Contracts or orders
47、 should specify the following provisions for preproduction inspection. 6.2.1.1 Whether preproduction inspection is required. When a contractor is in continuous production of the suspension lugs from contract to contract, con- sideration should be given to waive the preproduction inspections. If prep
48、roduction inspection is required, indicate: (a) where the preproduction inspection is to be conducted (at the contractors plant or Government or commercial laboratory). (b) that the approval of preproduction samples or the waiving of the preproduction inspection shall not relieve the contractor of h
49、is obligation to fulfill all other requirements of the specification and contract. 6.3 Data - For the information of Contractors and Contracting Officers, any of the data specified in (a) subparagraphs below, (b) applicable documents listed in Section 2 of this specification, or (c) referenced lower-tier documents need not be prepared for the Government and shall not be furnished to the Government un
