1、 ENGINEERING MATERIAL SPECIFICATION Material Name Specification Number Date Para No. Revisions Rev 02 2012 04 12 N Status No usage or replacement N. Benipal, NA 1978 08 30 Metricated & Retyped PCR-RD-782440-P2 1964 06 26 Released CP5-447352 Page 1 of 4 GASKET, VULCANIZED FIBER BASE/NITRILE BUTADIENE
2、 ESW-M8G98-A RUBBER COATED NOT TO BE USED FOR NEW DESIGN 1. SCOPE: The material defined by this specification is a hard vulcanized fiber base material coated with nitrile butadiene rubber. 2. APPLICATION: This specification was released originally for material used as gasket for sealing rear axle ho
3、using covers, transmission extension housings, oil pumps to blocks and hydraulic lift cover plates. 3. REQUIREMENTS: 3.1 VULCANIZED FIBER BASE MATERIAL Shall be a commercial grade of vulcanized fiber made from cotton base paper which has been chemically vulcanized to produce a hard fiber material co
4、nforming to ASTM D 710. 3.2 COATING MATERIAL Shall be a nitrile butadiene rubber which is relatively unaffected by hot oil (93-149 c) without appreciable flow of coating. The coating shall be resistant to petroleum, aromatic hydrocarbons and mixtures thereof. The properties of the coating material s
5、hall be determined on slab stock submitted as representative of the coating on the composite gasket. 3.2.1 Tensile Strength, min 1100 psi (7.6 MPa) (ASTM D 412) 3.2.2 Compression Set, max 30% (ASTM D 395, Method “A“, 400 psi (2.8 MPa) load, 70 h at 102 +/- 3 C) 3.2.3 Hardness, Durometer “A“ 75 - 85
6、(ASTM D 2240) 3.2.4 Compressive Deflection 40 - 50% (ASTM D 575, Method “B“, 1000 psi (6.9 MPa) load) ENGINEERING MATERIAL SPECIFICATION ESW-M8G98-A Page 2 of 4 3.2.5 Immersion in Liquids Immersion Fluids Test Conditions Volume Change ASTM Fuel “A“ 22 h at 23 +/- 2 C -5 to +10% ASTM Fuel “B“ 22 h at
7、 23 +/- 2 C 0 to +25% ASTM Oil No. 1 70 h at 149 +/- 1 C -20 to +5% ASTM Oil No. 3 70 h at 149 +/- 1 C -10 to +20% 3.2.6 Thickness Shall be specified on the engineering drawings and shall be equally distributed on each side. Variation of thickness shall not exceed 20% of total thickness on a side. 3
8、.3 COMPOSITE GASKET MATERIAL 3.3.1 Thickness As specified on engineering drawings Test Method: Condition test specimen for 22 h at 23 +/- 2 C and of 50 +/- 2% R.H. Measure the thickness in accordance with ASTM D 645, Method “A“, except that the diameter of the pressure foot shall be 0.504 +/- 0.001
9、in (12.80 +/- 0.03 mm). Remove the rubber coating with methyl ethyl ketone to measure thickness of base material. Allow methyl ethyl ketone to dry off completely before any tests are performed on base material. 3.3.2 Compressibility Under As specified on Load of 1000 psi (6.9 MPa) engineering drawin
10、gs Test Method: Condition test specimen as in para 3.3.1, then measure compressibility in accordance with ASTM F 39, except samples shall be plied to 0.100 in (2.54 mm) minimum. The test specimen shall be centered upon the anvil and a preload of 100 psi (690 kPa) shall be applied and maintained for
11、a period of 15 s at the end of which time the distance between the penetrator and anvil shall be recorded. This measurement represents the preload thickness (PT) of the test specimen. The compressibility load shall immediately be applied in a slow manner so that the full load of 1000 psi (6.9 MPa) i
12、s attained within 10 s. The compressibility load shall be maintained for 30 s, at the end of which time the distance separating the penetrator and anvil shall again be recorded. This measurement represents the compressed thickness (CT) of the specimen. The load then shall be immediately reduced to t
13、he original preload for a period of 1 min, at the end of which time the distance between the penetrator and the anvil shall be recorded. This measurement represents the recovered thickness (RT) of the specimen. A minimum of 3 tests shall be run on separate specimens. ENGINEERING MATERIAL SPECIFICATI
14、ON ESW-M8G98-A Page 3 of 4 Compute compressibility as: % Compressibility = PT - CT - x 100 PT 3.3.3 Recovery As specified on engineering drawings Test Method: Same as para 3.3.2 Compute recovery as follows: % Recovery = RT - CT - x 100 PT - CT 3.3.4 Compressive Strength, min 20 000 psi (138 MPa) Tes
15、t Method: When a pressure foot of 0.505 in (12.83 mm) diameter is used, the part shall not rupture or show other signs of failure. 3.3.5 Compression Set As specified on (ASTM D 395, Method “A“, engineering drawings may be plied to required thickness, 400 psi (2.8 MPa) load, 70 h at 102 +/- 3 C) 3.3.
16、6 Flow of Coating at 149 C When compressed 15% of its thickness between rigid, smooth, flat plates and heated in ASTM No. 3 oil at 149 C for 1 h, the rubber coating shall show no evidence of flow over the edge of the test specimen. 3.4 ADHESION COATING No separation of the coating from the base when
17、 immersed in ethylene dichloride for 5 min. 3.5 SUPPLIERS RESPONSIBILITY Material supplied to this specification must be equivalent to that originally approved. Changes in formulation or processing shall not be made without prior approval as described in Supplier Procedure I-A. 4. APPROVAL OF SUPPLI
18、ERS: Suppliers to this specification must be approved by the affected product engineering office. Procedure for gaining approval of a specific material to a new/existing ES-M specification is contained in Supplier Procedure I-A. Approved new suppliers will be added to the Engineering Materials Appro
19、ved Source List. ENGINEERING MATERIAL SPECIFICATION ESW-M8G98-A Page 4 of 4 5. GENERAL INFORMATION: This information is for direction of the user and is not a requirement for the supplier. Method of Specifying ESW-M8G98-A Vulcanized fiber thickness +/- Tolerance Coating thickness, each side +/- Tolerance Composite material compression set, max % Compressibility under 1000 psi (6.9 MPa), max % Recovery, min %
