SAE AMS 7267G pdf download

SAE AMS 7267G pdf download.Rings, Sealing, Silicone (vSI) Rubber Heat-Resistant,Low Compression Set 70 – 80.
1.1 Form:
This specification covers a silicone (VSI) rubber in the form of molded rings,
1.2 Application:
These rings have been used typically as sealing rings for service from -65 to ÷260 °C (-85 to ÷500
°F) in contact with air, but usage is not limited to such applications. The cross-section of such rings is usually not over 0.275 inch (6.98 mm) in diameter or thickness.
1.3 Safety-Hazardous Materials:
While the materials, methods, applications, and processes described or referenced in this specification may involve the use of hazardous materials, this specification does not address the hazards which may be involved in such use. It is the sole responsibility of the user to ensure familiarity with the safe and proper use of any hazardous materials and to take necessary precautionary measures to ensure the health and safety of all personnel involved.
2. APPLICABLE DOCUMENTS:
The following publications form a part of this specification to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of the purchase order.
4.2.3 Preproduction Tests: Tests for all technical requirements are preproduction tests and shall be performed prior to or on the first-article shipment of rings by the manufacturer, when a change in ingredients and/or processing requires reapproval as in 44.2, and when purchaser deems confirmatory testing to be required.
4.2.3.1 For direct U.S. Military procurement, substantiating test data and, when requested, preproductiori test material shall be submitted to the cognizant agency as directed by the procuring activity, contracting officer, or request for procurement.
43 Sampling and Testing:
Shall be as follows:
4.3.1 For Acceptance Tests: Sufficient rings shall be taken at random from each lot to perform all required tests; the number of determinations for each requirement shall be as specified in the applicable test procedure or, if not specified therein, not less than three.
I4.3.1.1 A lot shall be all rings of the same size from the same batch of compound processed in one continuous run and presented for manufacturers inspection at one time.
4.3.1.2 A batch shall be the quantity of compound run through a mill or mixer at one time.
4.3.1.3 When a statistical sampling plan has been agreed upon by purchaser and supplier, sampling shall be in accordance with such plan in lieu of sampling as in 4.3.1 and the report of 46 shall state that such plan was used.
4.3.2 For Periodic Tests: As agreed upon by purchaser and supplier.
4.3.3 For Preproduction Tests: As agreed upon by purchaser and supplier and as follows:
4,3.3.1 Specimens for the compression-deflection test shall be discs cut from molded slabs and stacked to 0.500 inch ± 0.010 (12.70 mm ± 0.25) thickness.
4,3.3.2 Specimens for the polymer reversion test shall be discs 1.129 inches ± 0.005 (28.68 mm ± 0.13) in diameter stacked to a total thickness of 0.500 to 0.550 inch (12.70 to 13.97 mm).
4.4 Approval:
14.4.1 Purchaser may request sample rings for evaluation before rings for production use are supplied.
4.4.2 Manufacturer shall establish, for each size of ring, process control factors which will produce rings meeting the technical requirements. These shall constitute the approved procedure and shall be used for manufacturing production rings. If necessary to make any change in process control factors, manufacturer shall submit for reapproval a statement of the proposed changes in ingredients and.or processing and, when requested, sample rings. Production rings incorporating the revised procedures shall not be shipped prior to receipt of reapproval.
4.4.2.1 Process control factors for producing rings include, but are not limited to, the following:
Compound ingredients or proportions thereof within established limits
Sequence of mixing compound ingredients and associated time, temperature, or work input controls
Type of mixing equipment
Method and equipment for preparing prelorms
Basic molding procedure (compression, transfer, injection)
Curing time, temperature, and pressure, maintained within statistically derived control limits
Finishing methods
Methods of inspection.