1、MIL-L-819 13A(AS) * Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Engineering Specifications and Standards Department (Code 931, Naval Air Engineering Center, Lakehurst, NJ 08733, by using the
2、 self-addressed Standard- ization Document Improvement Proposal (DD Form 1426) appearing at the end of 15 December 1981 SUPERSEDING MIL-L-81913(AS) 5 January 1973 MILITARY SPECIFICATION LEATHER, CATTLEHIDE, VEGETABLE TANNED, FOR PACKING AND SEALS This specification is approved for use by the Naval A
3、ir Systems Command, Department of the Navy, and is available for use by all Departments and Agencies of the Depart- ment of Defense. 1. SCOPE 1.1 Scope. This specification covers the requirements for one type of vegetable tanned cattlehide leather. 2. APPLICABLE DOCUMENTS 2.1 Government documents. *
4、 2.1.1 Specifications and standards. Unless otherwise specified, the following specifications and standards of the issue listed in that issue of the Department of Defense Index of Specifications and Standards (DoDISS) specified in the solicitation form a part of this specification to the extent spec
5、ified herein. SPECIFICATIONS - FEDERAL QQ-A-250/4 - Aluminum Alloy 2024, Plate and Sheet. QQ-B-626 - Brass, Leaded and Nonleaded, Rod, Shaped, Forgings, and Flat Products with Finished Edges (Bar and Strip). QQ-B-750 - Bronze, Phosphor; Bar, Plate, Rod, Sheet, Strip, Flat Wire, and Structural and Sp
6、ecial Shaped Sections. MILITARY M Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-S-18729 MIL-L-43432 STANDARDS FEDERAL FED-STD-311 MILITARY - Steel Plate, Sheet, and Strip, Alloy, 4130, Aircraft Quality . - Leather, Packaging and Packing of. - L
7、eather, Methods of Sampling and Testing. MIL-STD-105 - Sampling Procedures and Tables for Inspection by Attributes. (Copies of specifications and standards required by contractors in connection with specific acquisition functions should be obtained from the contracting activity or as directed by the
8、 contracting officer.) 2.1.2 Order o precedence. In the event of conflict between this specification and the references cited hereiii, the text of this specification shall take precedence. 3. REQUIREMENTS 3.1 Materials. The leather shall be made from prime quality cattlehide, con- taining no holes o
9、r brands in the bend area. , 3.2 Tannage. The leather shall be vegetable tanned. 3.3 Impregnation. The leather shall be impregnated with a mixture of oils . and greases or other compounds applicable to conditions of intended use. 3.4 Physical requirements. 3.4.1 Trim. The leather shall be furnished
10、in the form of bends and shall be trimmed to conform with the definition of bends as listed under “Definition of Terms“ in FED-STD-311. The area in terms of square feet shall be legibly marked in the butt area of the flesh side of the leather. 3.4.2 Thickness. The thickness of the leather shall be 8
11、 oz. ?- 1 oz. NOTE: 1 ounce = 1/64 inch. 3.4.3 Finish. The leather shall be undyed with no surface finish. * 3.4.4 Corrosive effect. The leather shall be non-corrosive and shall show no signs of dulling the polished surfaces when tested as specified in 4.3. 3.4.5 Resistance to low temperature. The l
12、eather shall remain pliable and flexible when tested as specified in 4.3.1. 3.4.6 Resistance to high temperature. The leather shall not crack when tested as specified in 4.3.2. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-BL913A 3 = 999990
13、6 0405270 T = Characteristic Requirement Total ash, percent, max - i/ 0.35 Water soluble material, percent, max L/ 12.1 i MIL-L-819 13A(AS) I“ A * 3.4.7 Tensile strength. The leather parallel with the backbone shall have a tensile strength of 4500 pounds per square inch and the leather perpendicular
14、 to the backbone shall have a tensile strength of 3000 pounds per square inch when tested as specified in 4.3. 3.4.8 Chemical requirements. The chemical requirements of the leather shall be as specified in table I when tested as specified in 4.3. 3.5 Workmanship. The leather shall conform to the qua
15、lity and grade of product established by this specification. The occurrence of defects shall not exceed the applicable acceptable quality levels. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. Unless otherwise specified in the con- tract or purchase order, the contractor is respo
16、nsible for the performance of all inspection requirements as specified herein. Except as otherwise specified in the contract or purchase order, the contractor may use his own or any other facilities suitable for the perormance of the inspection requirements specified herein, unless disapproved by th
17、e Government. The Government reserves the right to perform any of the inspections set forth in this specification where such inspections are deemed necessary to assure supplies and services conform to prescribed requirements. * 4.2 Classification of inspection. The inspection requirements specified
18、herein are classified as quality conformance inspection. inspection shall consist of all the examinations and tests required by-this specification. Sampling for inspection shall be performed in accordance with FED-STD-311, except where otherwise indicated hereinafter. The qualify conformance 4.2.1 C
19、omponent and material inspection. In accordance with 4.1 above, components and materials shall be tested in accordance with all the requirements of referenced specifications, drawings and standards unless otherwise excluded, amended, modified or qualified in this specification or applicable acquisit
20、ion documents. 4.2.2 Examination of the end item. The leather shall be examined for the defects listed in 4.2.2.1 and 4.2.2.2. The sample unit for these examinations shall be one bend. The lot size shall be expressed in units of one bend. Any sample unit containing one or more defects shall be class
21、iied as a defective unit. Sampling for these examinations shall be performed in accordance with 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-L9L3A 83 W 7997906 0405273 3 W MIL-L-81913A(AS) FED-STD-311, except that a sample size of 15 and a
22、 rejection number of 2 shall be applicable for thickness determinations on lots consisting of 51 or more units of product. Separate examinations shall be performed for visual and dimensional characteristics, but the same sample may be used for each exam- ination. 4.2.2.1 Visual examination. Examine
23、Defect Material Not as specified. Trim Not a bend. Color Color not natural as produced by tanning Finish Not as specified. Quality of leather Cut, scratch, hole or brand. process. NOTE: Light or well healed scratches, well healed grub damage, light fat wrinkles or slight stains shall not be classifi
24、ed as defects. 4.2.2.2 Dimensional examination. Examine Defect Area (expressed in Not as marked on the bend. terms of square feet) Thickness i/ Not as specified. Marking Omitted, illegible or not in area specified. - i/ Thickness shall be determined in accordance with method 1011 of of FED-STD-311,
25、except that no individual thickness measurement shall be less than the minimum or greater than the maximum Specified. 4.2.3 Examination of packaging requirements. An examination shall be made in accordance with the provisions of MIL-L-43432 to determine that the packaging, packing and marking comply
26、 with the requirements of section 5. * 4.3 End item testing. The methods of testing specified in FED-STD-311, wherever applicable and as listed in table II, shall be followed. Sampling procedures and location from which the sample unit is to be obtained shall be in accordance with FED-STD-311. All t
27、est results shall contain the individual values utilized in expressing final result. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-b MIL-L-81913A(AS) 3 TABLE II. Test Methods. Corrosive effects of leather Resistance to low temperature Resistance
28、to high temperature - i/ The contractor shall retain in his possession, and have available for inspection by the Government representative, documental evidence showing that the item conforms to the requirement for finish. The Government reserves the right to check test the item to verify its conform
29、ance. The following metals shall be used: - 2/ Specification Material QQ-A-250/4 QQ-B-626 QQ-B-750 MIL-S-7720 MIL-S-18729 Aluminum Brass Bronze Stainless steel, condition A Steel - 3/ The number of tests in each direction shall be 15. * 4.3.1 Resistance to low temperatures. The resistance to low tem
30、perature shall be determined as specified in Method 7211 of FED-STD-311, except that the specimen shall be exposed to a temperature of -56.7O & l.lC (-7O0F I2OF) for 24 hours. 4.3.2 Resistance to high temperature. The specimen for test shall be approximately 2 by 2 inches cut from the sample unit of
31、 leather. It shall be folded crosswise sharply upon itself with the grain side out and shall be ex- posed to a-temperature of 126.7O f 1.l0C (260O & 2OF) for 18 hours. At the end of this period the specimen shall be examined for cracks in the area around the bend. 5. PACKAGING 5.1 Packaging. Packagi
32、ng shall be level A or C as specified (see 6.2) 5.1.1 Levels A and C. Leather shall be packaged in accordance with the applicable requirements of MIL-L-43432. 5.2 Packing. Packing shall be level A, B, or C as specified (see 6.2). 5.2.1 Levels A, B, and C. Leather shall be packed in accordance with t
33、he applicable requirements of MIL-L-43432. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- -_-_I_- _- _I- MIL-L-LSL3A 3 - 7799906 0405273 5 - MIL-L-81913A(AS) c . 5.3 Marking. In addition to any special marking required by the contract or order, i
34、nterior packages and shipping containers shall be marked in accordance with MIL-L-43432. 6 6 sea 6 NOTES 1 Intended use. The leather is intended for use as gaskets, padding, s, and retainers. 2 Ordering data. Acquisition documents should specify the following: a. Title, number and date of this speci
35、fication. b. Selection of the applicable levels of packaging and packing (see 5.1 and 5.2). 6.3 Changes from previous issue. The margins of this specification are marked with an asterisk to indicate where changes (additions, modifications, corrections, deletions) from the previous issue were made. T
36、his was done as a convenience only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contractors are cautioned to evaluate the requirements of this .document based on the entire content irres- pective of the marginal notations and relationship to the last previous issue. Preparing activity: Navy - AS (Project No. 8330-N180) *V.S. QOVKRNMENT PRINTINQ OFFICE: 1.8240SQZZl42a 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
