1、MIL-L-50427A 13 m 9977706 0327250 MIL-L-50429A(MU) 31 October 1972 SUPERSEDING MIL-L-50429(MU) 23 May 1969 MILITARY SPECIFICATION LAMINATE, ACETAL AND CLOTH, (FOR USE WITH 81m AMMUNITION) 1. SCOPE 1.1 Scope.-This specification covers a laminate of acetal sheeting bonded by adhesive to cloth for usag
2、e as propellant increment bag material for 81MM ammunition. 2. APPLICABLE DOCUMENTS 2.1 The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of this specification to the extent specified herein. S PEC IF1 C AT IONS MILITARY MIL-A-2 550 -A
3、mmunition and Special Weapons, General Specification For STANDARDS MILITARY MIL-STD-105 -Sampling Procedures and Tables for MIL-STD-109 -Quality Assurance Terms and Definitions MIL-STD-129 -Marking for Shipment and Storage MIL-STD-286 -Propellants, Solid: Sampling, Examination and Testing MIL-STD-11
4、68 -Lot Numbering of Ammunition Inspection by Attributes (ABC-STD-105) DRAWINGS ARMY 9233369 -Charge A, Propellant Increment, M90A1 Mortar Cartridge, 81MM 9233371 -Charge B, Propellant - Increment, M90A1 Mort: r Cartridge, 81MM FSC: 1395 A Provided by IHSNot for ResaleNo reproduction or networking p
5、ermitted without license from IHS-,-,-I MIL-L-504ZA 13 m 777?Ob 0327251 T B!E I 3, REQUIREMENTS 3.1 Materials.-The larninate shall be made from materials $a. accordance with drawings. 9233368 and 9233370 , 3.2 Physical Requirements .-The laminate shall comply with I I the z-equirements specffied in
6、Table I, Properties Tensile Strength Basis Weight (applicable to silk-acetal laminate) Basis Weight (applicable to acrylic-acetal 1ami;nate) Roll width (Charge.A Bag) Requirements Test Methods 9.0 lbs min. 4.4.1 3.0 02s. per sq. yd., max. 4.4.2 3.5 02s. per sq. yd., Max. 4.4.2 2.375 f- . 063 inches
7、4.4.3 3.3 Strength of Heat Seal.-The laminate, upon being heat sealed to itself on the acetal side, shall withstand application of 8 statio load of 2.5 pounds per lineal inch, minimum, without peel-back of the heat seal and without tensile failure of the -area adjacent to the heat seal when tested a
8、s specified in 4.4.4. 3.4 First Article Inspection.-A first article sample shall be submitted in accordance with.pafa. 4.2.2. Samples shall be chosen, I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-L-50927A 13 m 7777706 0327252 1 m tested and
9、 observed for compliance with requirements in accord- ance with this specification. 3.5 Workmanship.-The laminate shall be free from breaks, cracks, creases, loss of bond or flaws of any kind, and foreign materials. 3.6 Ballistic Comparison Test.-First article samples shall be tested in accordance w
10、ith para. 4.4.5 to determine compliance with the Ballistic Comparison Test requirements specified therein. 3.7 Vacuum Stability Test.-Samples shall be tested in accordance with para. 4.4.6 to determine compliance with the Vacuum Stability Test requirements specified therein. 4. QUALITY ASSURANCE PRO
11、VISIONS 4.1 Responsibility for inspection.-Unless otherwise specified 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 oth
12、er facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in the specification where such inspections are deemed necessary to assure supplies and serv
13、ices conform to prescribed requirements. Reference shall be made to Standard MIL-STD-109 in order to define terms used herein. The provisions of Specification MIL-A-2550 shall apply. 4.1.1 Submission of product,-At the time the completed lot of product is submitted to the Government for acceptance t
14、he contractor shall supply the following information accompanied by a certificate which attests that the information 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
15、. Drawing and specification number and date, together with identification and date of changes thereto. c. A statement of findings on the physical properties of the material inaddition to a statement that all material purchased by the contractor meets requirements, when such material is controlled by
16、 Government or commercial specifications referenced in any of the contractual documents, and that certi- ficates of conformance are on file and available for review. d. Number of items in the lot. e. Date submitted. The certificate shall be signed by a responsible agent of the certifying organizatio
17、n. The initial certificate submitted shall be substantiated by evidence of the agents authority to Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-50429A 13 W 9999906 0327253 3 W k the course of the contract, this authority is vested in another
18、 agent of the certifying organization. Substantiation of the agent rs authority 4.2 Inspection Provisions 4.2.1 Lot formation.-The term “inspection lot“ as used in this specification is defined as an essentially homogeneous collection of units of product from which a representative sample is drawn a
19、nd inspected to determine conformance with applicable requirements. onXy %hat quantity of units from which the sample was drawn afld shall not be construed to represent any prior or subsequent quantiies presented for inspeckion. Homogeneity shall be considered to exist provided the inspection lot ha
20、s been produced by one manufacturer, in one unchanged process using the same materials and methods in accordance with the same drawings, same rawing revisions, same spcifications and same specification revisions and complies with the provisions for submission of product as specified in mL-STD-lO5. C
21、hanires to the process, YpeCifications, or Grawings not ffecting safety, performance, Iht-grchangeability , or storage, as determined by the Government shaX1 not be demed to arlter the homogeneity of an inspection lot. All ma6erial submitted fur inspection in accordance with this specification shall
22、 comply with the homogeneity criteria speci?ied herein regardless of the type of sampling procedure which is being applied to determine conformance with requirements. Lot numbering, as required, shall be in accordance with MIL-STD- 1168. The safnple selected shall represent 4.,2.2 -First article ins
23、pection 4.2.2.1 Submission.-The contractor shall submit a first article sample as designated by the contracting officer for evaluation in accordance with -4.2.2.2. The first article sample shall consist of one lot of laminated material which has been produced by the contractor and has been manufactu
24、red by the same proauction process, using ppocedures and equipment which will be used in fulfilling the contract. All materials including the packaging and packing shall be obtained from the same Source of supply as will be used in regular production. Prior to submission, the contractor shall inspec
25、t the sample to the degree necessary to assure that it conforms to the . requirements of the contract and submit a record of this inspection with the sample, including statements of findings for materials, processes and tests. A sample containing known defects shall not be submitted unless specifica
26、lly designated by the contracting officer, A first article sample shall also be submitted as Q Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-50427A 13 M 777770b 0327254 5 M directed by the contracting officer, whenever there is a lapse in pro
27、duction for a period in excess of 90 days or when- ever a change occurs in the manufacturing process, materials used, drawing or specification such as to significantly affect product uniformity as determined by the Government. 4.2.2.2 any of the applicable requirements, the first article sample shal
28、l be rejected. Rejection.-If the laminate fails to comply with 4.3 Sampling Plan.-A group of five (5) rolls of Charge A Bag width and five (5) rolls of Charge B Bag width shall be randomly selected from each lot. A sample shall be removed from each roll, tested and inspected for compliance with the
29、requirements of this specification. No sample shall be taken from the first or last five yards of a roll. The sample shall be conditioned as specified in ASTM Designation D618. The test results from each roll shall be averaged for reporting purposes. Failure of any individual sample to conform to th
30、e requirements of this specification shall cause rejection of the entire lot. 4.4 Test methods and procedures 4.4.1 Tensile strength, Major Defect.-The tensile strength shall be determined in accordance with ASTM Designation D882, Method B. 4.4.2 Basis Weight, Major Defect .-The basis weight of the
31、laminate shall be determined in accordance with ASTM Designation D646. 4.4.3 Roll width, Major Defect.-The width of the rolls selected for sampling in accordance with 4.3 shall be gaged for compliance with requirements as specified in Table I. 4.4.4 Strength of Heat Seal, Major Defect.-Two pieces of
32、 laminate selected in accordance with 4.3 shall be heat sealed together on the acetal side. The width of the seal shall be 1/32 inch min. and 1/8 inch maximum, The specimen size shall be one inch in width. One leg of the specimen shall be clamped so that the specimen hangs freely. The required load
33、(see 3.3) shall be applied to the free end in such a manner as to avoid impact loading the heat seal. The load shall be allowed to act for one minute after which the seam shall be examined for compliance with the requirement as specified in 3.3. 4.4.5 Ballistic Comparison Test, Critical Defect.- Thi
34、s test wil be conducted at a Government Proving Ground utilizing 81m rounds containing propellant increment bags manufactured 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-50427A 13 M 7777706 0327255 7 &wording to drawings 9233368, 9233369,
35、 9233370,. and 92.33371. Ballistic test rounds shall be assembled using increment bags made from the first article sample and metal parts from the same lots of metal parts used to assemble the ballistic reference rounds. The increment bags on the reference rounds shall be selected from present produ
36、ction at the time of first article testing. Testing details shall be in accordance with Table II and the following: All groups shall be fired at an elevation of 45 degrees using a 3.209 inch, max. mortar tube at a rate of 12 rounds pep minute. The test rounds shall not s&gnifieantly increase the sta
37、ndard deviation of velocity nor the mk3fiTe rate, In addition, the level of velocity shall not clewease as compareq to the reference. rounds. TABLE II ZQNE TEST ROUNDS 4.4.6 Vacuum Stability Test, Critical Defect.-The procedure for this test is as specified in Standard MIL-STD-286, Test Method 403,2
38、,2. The following formula shall be used to determine acceptance Qr rejectton: A + B t 5.0 mls.7 C where: A = Numbers of mls. of gas evolved by 2.5 gr of M9 propellant E = Numbers of mls. of gas evolved by 2.5 gr of laminate material C = Number of mls, of gas evolved by 5.0 gr of a mixture (1:l in fo
39、rtg hours, in forty hours. ratio) of Mg prapellant and finely cut up laminate material. 5, PREPARATION FOR DELIVERY ciel Packing Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-50427A 13 W 7777706 032725b 7 5.1.1 Level C.-The laminate shall be
40、packed in a manner that will insure safe delivery from the manufacturers plant to the first receiving activity, and in conformance with appli cab le carrier regulations . 5.2 Marking.-Interior packages, and exterior containers, shall be marked in accordance with Standard MIL-STD-129. 6. NOTES 6.1 Or
41、dering data.-Procurement documents should specify: a. Title, number and date of this inspection. b. Provisions for submission of first article samples. 6.2 Test results.-A copy of the test results should be forwarded withsn five days of completion of tests to: Commanding Officer, Picatinny Arsenal, Dover, New Jersey, 07801, ATTN: SMUPA-&A-A-A. Custodian: ARMY-MU Preparing activity: ARMY-MU Project Number: 1395-A- 001 7 U. S. GOVERNMENT PRINTING OFFICE: 1973-714-542/3676 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
