SAE AS 81934C pdf download

SAE AS 81934C pdf download.(R) Bearings, Sleeve, Plain and Flanged, Self-Lubricating
3. REQUIREMENTS
3.1 Aerospace Standard (AS) Sheets The individual item requirements shall be as specified herein and in accordance with the applicable AS sheets. In the event of any conflict between the requirements of this standard and the AS sheet, the latter shall govern. 3.2 Qualification Products furnished under this standard shall be products which are authorized by the qualifying activity for listing on the applicable Qualified Products List (QPL-AS81934) at the time of award of contract (see 4.3, 6.3, and 6.3.1). See Qualified Products Database (QPD) at https://assist.dla.mil/, https://qpldocs.dla.mil/, or https://quicksearch.dla.mil/. 3.2.1 Product Change Any change in product design, description, materials, processing procedures, or plant location shall be reported to the qualifying activity and may require requalification of the product to an extent determined by the qualifying activity. Any other specific changes, which must be brought to the qualifying activity’s attention, shall be identified in the qualification notification letter.3.2.2 Product Manufacture Except for the bonding operations, the manufacturer is permitted to subcontract manufacturing operations without violating the requirements of 3.2.1. The bonding operations shall be performed in the plant listed on the Qualified Products List. Manufacture of the self-lubricating liner material may also be subcontracted. Any change in (1) the liner manufacturer, (2) the liner manufacturing procedures, or (3) the materials used in manufacture of the liner will require requalification to an extent determined by the qualifying activity. The manufacturer is responsible for meeting all requirements of the standard and for the quality of the end product, whether it is manufactured totally in-house or some of the operations are performed by a subcontractor. Inherent in the responsibility for the end product is the responsibility to verify that the subcontractor’s processes meet standard requirements. 3.3 Materials Material for the sleeve and liner shall conform to the applicable AS sheet. PTFE shall be included in the liner in such a manner that the bearing will conform to all requirements of this standard. 3.3.1 Corrosion Resistant Steel Finishes Corrosion resistant steel (CRES) sleeve bearings shall be finished by cadmium plating, zinc-nickel plating, or passivating in accordance with 3.3.1.1 or 3.3.1.2, and as defined with the finish option in the part number. 3.3.1.1 Cadmium or Zinc-Nickel Plating When required by the part number, plating of the outside diameter of CRES sleeve bearings shall be in accordance with AMS-QQ-P-416, Type II, Class 2, or AMS2417, Type 2, Grade A or B, and the applicable AS sheet. The 23-hour bake time of the plating specification shall be waived to prevent over-curing of the liner adhesive. Hydrogen embrittlement testing is not required. Dimensions in AS81934/1 and AS81934/2 apply. For the AMS2417 plating, only Grade B shall be permitted on bearings after June 1, 2016.3.3.1.2 Passivation When required by the part number, exposed metallic surfaces of unplated CRES sleeve bearings shall be passivated per AMS2700, Method 1 (Nitric Acid) or Method 2 (Citric Acid), or passivate in accordance with ASTM A967, citric acid passivation, using CITRIC 1, CITRIC 2, or CITRIC 3 solutions after all metal removal operations, regrinding inclusive, have been completed. Passivation may be performed before or after bonding, at the bearing manufacturer’s option. A permissible method for determining passivity is the copper sulfate test defined in ASTM A967 or AMS2700. 3.3.2 Aluminum Finishes Aluminum sleeve bearings shall be anodized per MIL-A-8625, Type I or II, or chemical film treated per MIL-DTL-5541. 3.4 Design Bearing design shall conform to that shown on AS81934/1 and AS81934/2. 3.5 Construction The liner shall be so secured that all relative motion will be between the liner and the shaft. Once the liner is installed, a gap of 0.025 inch maximum between the ends of the liner where they meet on the inside diameter of the bearing is allowed. This 0.025 inch maximum gap shall have resin covering the full gap area so no substrate is exposed. 3.5.1 Dimensions and Tolerances Dimensions and tolerances shall be as specified on the applicable AS sheet. Dimensions not shown shall be at the option of the manufacturer. Lined IDs shall be inspected per ARP5448/9.