SAE AS 518A:2001 pdf download

SAE AS 518A:2001 pdf download DRIVE ACCESSORY 3.000 PILOT DIAMETER – QAD
5.2Screws
Unless otherwise specified, use hexagon head screws or socket head screws of property class 1 0.9 (minimum), as specified in ISO 898-1 , or equivalent inch (SAE grade 8 hex head cap screws or ASME 1 8.3 socket head cap screw of ASTM A574 material) screws. Inch screws shall not be used for new design.
5.3 Washers
The use of hardened washers is recommended. Washers, if used, shall conform to ISO 7089 Type A, Class 300HV and be sized for the corresponding screw except for the DN 32 (-20) type 2 (inch) size which shall conform to ASME 1 8.22.1 type B narrow (HV300). Plain washers conforming to ASME B1 8.22.1 , type B narrow (HV300) series, may be substituted when using Type 2 screws except for the DN 32 (-20) size. The ISO 7089 washer might cause interferences if used with the inch screw in the DN 32 (-20) size.
5.4 O-ring Seals Connectors conforming to this International Standard use elastomeric seals. Unless otherwise specified, connectors are made and delivered with elastomeric seals for use within the specified working temperature range with petroleum base hydraulic fluids. The use of these connectors and elastomeric seals with other hydraulic fluids can result in a reduced working temperature range or can render the connectors unsuitable for the application. Manufacturers may supply, upon request, connectors with elastomeric seals for use with hydraulic fluids other than petroleum base hydraulic fluids which meet the specified working temperature range of the connectors. The O-rings in Tables 1 A and 1 B shall correspond to the size code, tolerance class A in ISO 3601 -1 and shall meet or exceed the O-ring quality acceptance criteria for grade N of ISO 3601 -3. Unless otherwise specified, the O-rings shall be of NBR (nitrile) with a hardness of 90 ± 5 IRHD measured in accordance with ISO 48.
6. CORROSION PROTECTION
6.1 External Surfaces The external surfaces of all carbon steel flanges shall be plated or coated with a suitable material that passes a 72-h salt spray test in accordance with ASTM B1 1 7 (ISO 9227). Any appearance of red rust during the 72-h salt spray test shall be considered failure, except for the following:
a. All internal fluid passages.
b. Edges such as hex points, serrations and crests of threads where there can be mechanical deformation of the plating or coating typical of mass-produced parts or shipping effects.
c. Areas where there is mechanical deformation of the plating or coating caused by crimping, flaring, bending and other post-plate metal forming operations.
d. Areas where the parts are suspended or affixed in the test chamber where condensate can accumulate. Parts manufactured to this standard shall not be cadmium plated. Hexavalent chromate coatings are not preferred for commercial and industrial usage due to environment reasons. Internal fluid passages shall be protected from corrosion during storage and shipping. Parts with changes in plating or coating shall be requalified to ensure assembly torque is not affected.
6.2 Screws and Washers Screws and washers shall meet the requirements of a 1 6-h salt spray test in accordance with ASTM B1 1 7 (ISO 9227). All screws shall be phosphate coated with an oil finish unless otherwise agreed upon by the purchaser and supplier. The use of a flat washer is recommended where possible. Torque values specified in this part of SAE J51 8 were determined using phosphate coated, oil finished screws.