1、 INCH-POUND MIL-PRF-17927D 27 September 2004 SUPERSEDING MIL-G-17927C 24 December 1986 PERFORMANCE SPECIFICATION GASKETS, FLAME RESISTANT HINGED CLOSURE This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers
2、gaskets for use on hinged closures where flame resistance and fume containment are required. 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 s
3、pecification 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 not
4、 they are listed. 2.2 Government documents. 2.2.1 Specifications, standards and handbooks. The following specifications, standards, and handbooks 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
5、 or contract. 2.2.1 Other Government documents, drawings, and publications. The following other Government documents, drawings, and publications 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
6、or contract. Comments, suggestions, or questions on this document should be addressed to Commander, Naval Sea Systems Command, ATTN: SEA 05Q, 1333 Isaac Hull Avenue, SE, Stop 5160, Washington Navy Yard DC 20376-5160 or emailed to commandstandardsnavsea.navy.mil, with the subject line “Document Comme
7、nt“. Since contact information can change, you may want to verify the currency of this address information using the ASSIST Online database at www.dodssp.daps.mil AMSC N/A FSC 5330 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-17927D 2 BURE
8、AU OF MEDICINE AND SURGERY (BUMED) BUMED INST 6270.8 - Procedures for Obtaining Health Hazard Assessments Pertaining to Operational Use of a Hazardous Material. (Copies of this document are available online at https:/bumed.med.navy.mil or from Bureau of Medicine and Surgery, Department of the Navy,
9、2300 E Street, NW, Washington, DC 20372-5300.) 2.3 Non-Government 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. AMERICAN SOCIETY FOR QUALITY
10、 (ASQ) ASQC Z1.4 - Sampling Procedures and Tables for Inspection by Attributes. (DoD adopted) (Copies of this document are available from www.asq.org or American Society for Quality, 600 North Plankinton Avenue, Milwaukee, WI 53203.) ASTM INTERNATIONAL D 412 - Standard Test Methods for Vulcanized Ru
11、bber and Thermoplastic Elastomers - Tension. (DoD adopted) D 1349 - Standard Practice for Rubber-Standard Temperatures for Testing. (DoD adopted) D 2000 - Standard Classification System for Rubber Products in Automotive Applications. (DoD adopted) D 2240 - Standard Test Method for Rubber Property -
12、Durometer Hardness. (DoD adopted) (Copies of these documents are available from www.astm.org or ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA, 19428-2959.) 2.4 Order of precedence. In the event of a conflict between the text of this document and the references cited herein, the te
13、xt of this document takes precedence. Nothing in this document, however, supersedes 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 subject to first article inspection in accordance with 4.2
14、. 3.2 Materials. The gaskets shall consist of a rubber core covered with a protective outer layer(s). The outer layer(s) shall adhere to the core and shall be coated with rubber. Asbestos material shall not be used. Gaskets shall not be lubricated with graphite or other materials. 3.2.1 Rubber core.
15、 The rubber core material shall be in accordance with ASTM D 2000 M5FE 310 A19B37EA14G11 (see Table I). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-17927D 3 TABLE I. Physical properties of rubber. Properties Values Initial Properties Hard
16、ness, durometer points, 5 30 Tensile strength, (min), pounds per square inch (PSI) 1450 Ultimate elongation (min), % 500 Compression set, max, %, 22h at 350 F 35 Oil immersion, No. 3 oil, 22h at 350 F, max volume change, % +80 Heat Resistance Change in hardness max, points 10 Change in tensile stren
17、gth max, % -50 Change in elongation max, % -50 Water Resistance Change in hardness, points 5 Change in volume, % 5 Tear Resistance 1015 to 1500 PSI load, min, pound force per inch (lbf/in) 143 3.2.2 Outer layer(s). The outer layer(s) shall protect the core. 3.3 Adhesion. The outer layer(s) shall adh
18、ere to the core such that stripping the outer layer(s) from the core causes cohesive failure. 3.4 Sealing durometer. The sealing durometer of the finished gasket shall be as specified in Table II. 3.5 Tensile strength. The gasket shall have a minimum tensile strength of 300 pounds per inch. 3.6 Flam
19、e and heat resistance. The finished gasket shall show no melting or loss of material when subjected to the heat test of 4.4.6. When subjected to the flame test of 4.4.6, the gasket shall burn for not more than 60 seconds. The outer covering shall hold its shape and texture when the gasket is subject
20、ed to the flame and heat tests . 3.7 Dimensions, tolerances and size. The dimensions for the finished gasket shall be as shown in Table II. The finished gasket shall be within a tolerance of plus 1/16 inch, minus 0 inch. No minus tolerance shall be permitted. Provided by IHSNot for ResaleNo reproduc
21、tion or networking permitted without license from IHS-,-,-MIL-PRF-17927D 4 TABLE II. Dimensions and construction (finished gasket). Number designation Shape Nominal size (inches) gasket cross-section Sealing durometer 1 3/4 x 3/4 45 + 5 2 1/2 x 1-1/4 55 + 5 3 1/4 x 1-1/4 55 + 5 4 3/4 x 1-1/4 15/16 x
22、 1-1/4 55 + 5 5 1x1 45 + 5 6 3/4 x 1-1/4 45 + 5 3.8 Length of reels. Gasket material shall be provided in 25- or 50-foot reels. 3.9 Toxicity. The gaskets shall have no adverse effect on the health of personnel when used for its intended purpose. The gaskets shall be assessed by the Navy Environmenta
23、l Health Center (NAVENVIRHLTHCEN) using the administrative Health Hazard Assessment (HHA). A flowchart for this process can be found as enclosure (1) of BUMEDINST 6270.8. The HHA is a review of the gaskets based on information submitted by the manufacturer, to assess health hazards associated with t
24、he handling, application, use and removal of the product. The gaskets shall not cause any environmental problems during waste disposal (see 4.4.7 and 6.5). 3.10 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used t
25、o the maximum extent possible provided that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. 3.11 Workmanship. The workmanship of the finished gasket shall be such as to meet all requirements of this specification. T
26、he gasket shall be smooth and free from cracks or other obstructions. 4. VERIFICATION 4.1 Classification of inspections. The inspection requirements specified herein are classified as follows: a. First article inspection (see 4.2). Provided by IHSNot for ResaleNo reproduction or networking permitted
27、 without license from IHS-,-,-MIL-PRF-17927D 5 b. Conformance inspection (see 4.3). 4.2 First article inspection. First article inspection shall consist of the examinations and the tests specified in Table III. 4.3 Conformance inspection. The conformance inspection shall consist of the examinations
28、and tests as specified in Table IV. Table III. First article inspection. Examinations, Measurements and Test Requirements Test Performed on Core Hardness 3.2.1 4.4.2 Tensile strength and elongation 3.2.1 4.4.2 Comparison set 3.2.1 4.4.2 Oil immersion (volume change) 3.2.1 4.4.2 Heat resistance 3.2.1
29、 4.4.2 Water resistance 3.2.1 4.4.2 Tear resistance 3.2.1 4.4.2 Performed on Finished Gasket Adhesion 3.3 4.4.3 Sealing durometer 3.4 4.4.4 Tensile strength 3.5 4.4.5 Flame and heat resistance 3.6 4.4.6 Dimensions, tolerances and size Toxicity 3.7 3.9 - 4.4.7 Table IV. Conformance inspection. Examin
30、ations, Measurements and Test Requirements Test Performed on Finished Gasket Adhesion 3.3 4.4.3 Sealing durometer 3.4 4.4.4 Tensile strength 3.5 4.4.5 Flame and heat resistance 3.6 4.4.6 Dimensions 3.7 4.3.1 Sampling. 4.3.1.1 Lot. For the purposes of sampling, examination, and tests, a lot shall con
31、sist of all gaskets of the same size, produced in one plant under essentially the same conditions, not exceeding 2500 feet and offered for delivery at one time. 4.3.1.2 Sampling for examination. As specified in 4.3.3, a random sample of reels shall be selected from each lot of gasket material for ex
32、amination. Examination shall be in accordance with inspection level II of ASQC Z1.4. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-17927D 6 4.3.1.3 Sampling for tests. Samples of gasket material shall be selected from each lot for the test
33、as specified in 4.3.2 at special inspection level S4 in accordance with ASQC Z1.4. Samples of core rubber shall be furnished with each lot in the form of two sample pieces 6 by 6 inches by 0.080 + 0.010 inch thick and one sample piece approximately 4 by 3 inches by 0.500 + 0.010 inch thick, or cut f
34、rom extruded core and supplied as slabs. The substitute samples shall be of the same material and equivalent core as that used in the lot of finished material offered for delivery. 4.3.2 Conformance tests. The samples selected for testing as specified in 4.3.1 shall be subjected to the tests as spec
35、ified in Table IV. If any of the samples tested fail to meet any of the requirements specified herein, it shall be cause for rejection of the entire lot. 4.3.3 Examination. Each of the samples taken as specified in 4.3.1.2 shall be examined visually for workmanship, appearance, dimensions and tolera
36、nce. Any reel in the sample containing one or more visual or dimensional defects shall not be offered for delivery. Noncompliance with any specified requirements or presence of one or more defects preventing or lessening maximum efficiency shall constitute cause for rejection. 4.4 Test procedures. 4
37、.4.1 Testing conditions. Unless otherwise specified, the testing conditions shall be in accordance with the temperature and humidity of conditioning room requirements in accordance with ASTM D 1349. 4.4.2 Core. The rubber core material shall be tested for the requirements of Table III in accordance
38、with ASTM D 2000. 4.4.3 Adhesion test. The outer layer(s) shall be stripped from the rubber core (and from each other) without the use of solvents. 4.4.4 Sealing durometer. The sealing durometer shall be determined in accordance with ASTM D 2240. The reading shall be taken on the finished gasket at
39、the point where the knife or striker bar is to contact the gasket in actual application. 4.4.5 Tensile strength. The tensile strength shall be determined in accordance with ASTM D 412. 4.4.6 Flame and heat resistance. A specimen of the finished gasket shall be held for 15 seconds with one face acros
40、s the flame of a Tirrill-type burner. The lower side of the gasket shall be held even with the tip of the blue cone of the flame. The temperature of the flame, measured with a pyrometer, shall be approximately 1600F at the tip of the blue cone. If a pyrometer is not available for measuring the tempe
41、rature, the tip of the blue cone of the flame shall be not less than 1 inch or more than 1-1/2 inches high. The specimen, when cut open at the exposed section, shall be examined for conformance to 3.6. In addition, a specimen of the gasket shall be held over a 1600F flame, as specified herein for no
42、t more than 60 seconds (or until the silicone core ignites or bursts into flame). The gasket, when removed from the burner flame, shall be examined for conformance to 3.6. 4.4.7 Toxicity. To determine conformance with the requirements of 3.9, the gaskets shall be evaluated using the HHA process. Suf
43、ficient data to permit a HHA of the product shall be provided by the manufacturer/distributor to the NAVENVIRHLTHCEN. To obtain current technical information requirements specified by the NAVENVIRHLTHCEN, see 6.5. 5. PACKAGING Packaging. For acquisition purposes, the packaging requirements shall be
44、as specified in the contract or order (see 6.2). When packaging of materiel is to be performed by DoD or in-house contractor personnel, these personnel need to contact the responsible packaging activity to ascertain packaging requirements. Packaging Provided by IHSNot for ResaleNo reproduction or ne
45、tworking permitted without license from IHS-,-,-MIL-PRF-17927D 7 requirements are maintained by the Inventory Control Points packaging activities within the Military Service or Defense Agency, or within the military services system commands. Packaging data retrieval is available from the managing Mi
46、litary Departments or Defense Agencys automated packaging files, CD-ROM products, or by contacting the responsible packaging activity. 6. NOTES (This section contains information of a general or explanatory nature that may be helpful, but is not mandatory.) 6.1 Intended use. The gasket material cove
47、red by this specification is intended to be used in scuttles, doors, and hatches located in the path of missile blast areas and also in fume-tight doors located in fire zone bulkheads. The gaskets covered by this document are military unique because they are used in missile blast areas, which the co
48、mmercial public does not have access to obtain or use. In addition, the gaskets must be able to retain fumes and withstand extreme temperature changes from room temperature to temperatures of 1600F for a minimum of 15 seconds. 6.2 Acquisition requirements. Acquisition documents should specify the fo
49、llowing: a. Title, number, and date of the specification. b. When first article inspection is required (see 3.1). c. Size or dimensions required (see 3.47 and 3.8). d. Testing conditions as required (see 4.4.1). e. Packaging requirements (see 5.1). f. Is NEHC toxicity evaluation required? (see 6.5). g. Is a Material Safety Data Sheet required? (see 6.4). 6.3 Fabrication. There are many material combinations that potentially could meet the
