SENSOR GP-SPEED 7W3355 - Caterpillar

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The illustrations 4 through 6 give examples of normal coupling wear.
Illustration 4 g01874997
Normal wear on the inner member
Illustration 5 g01875013
Normal wear on the inner member and outer member
Illustration 6 g01875014
Excessive amount of silicone lubricantAn excessive amount of silicone fluid was used during the field assembly of the coupling shown in illustration 6. The textured pattern was created by dust particles collected in the coupling. No harm has occurred to the coupling.The illustrations 7 through 12 give examples of normal coupling block wear.
Illustration 7 g01875016
Normal discolorationIt is normal for the blocks to discolor from blue to gray or black. The discoloration does not indicate that the blocks have been overloaded or that the blocks have suffered excessive wear.
Illustration 8 g01875017
Normal discoloration
Illustration 9 g01875018
The difference in wear patterns between leading blocks and trailing blocksIn illustration 9, the left hand block is a trailing block and the right hand block is a leading block. The leading block will always have a larger, more pronounced imprint from the coupling because it is compressed more and has a larger contact area with the metal.
Illustration 10 g01875019
Trailing block
Illustration 11 g01875020
Leading block
Illustration 12 g01875021
Leading block that was turned during inspectionThe illustrations 13 and 14 give examples of wear on the inner member and on the cover plate.
Illustration 13 g01875023
Wear on the inner member caused by contact with the cover plate
Illustration 14 g01875025
Cover plateWear on the metal parts of the coupling may be caused by the generator shaft position. The position of the shaft is not a significant problem. Testing has shown that operating with this slight interference has little impact on the vibration levels. Ensure that the generator shaft is centered axially prior to installation of the coupling. Adjust the shaft position by pushing, pulling, or prying on the generator hub. Never pry on the generator fan or on the exciter.The illustrations 15 and 16 give examples of blocks that are damaged and need to be replaced.
Illustration 15 g01875033
Block with deterioration
Illustration 16 g01875035
Block with deteriorationIf 12 or more of the blocks have begun to crack as shown in illustrations 15 and 16, replace all 24 of the blocks.