Basics
Furthermore, the roller’s inner surface constitutes a bearing part together with the bushing’s outer surface when the roller rotates on the rail. Therefore, it must be resistant to wear and still have strength against shock, fatigue, and compression. Cotter Pin, Spring Clip, T-Pin These are the parts that prevent the outer plate from falling off the pin at the point of connection. They may wear out during high-speed operation, there- fore, for this application, these parts require heat treatment.
1.2 ADVANTAGES AND DISADVANTAGES OF CHAIN FOR POWER TRANSMISSION AND CONVEYORS
1.2.1 Power Transmission Uses Power transmission machines use either chains, gears, or belts. Table 1.1 provides a comparison of typical applications. Usually, chain is an economical part of power transmission machines for low speeds and large loads. However, it is also possible to use chain in high- speed conditions like automobile engine camshaft drives. This is accomplished by devising a method of operation and lubrication. Basically, there are lower limits of fatigue strength in the gear and the chain, but not in the belt. Furthermore, if a gear tooth breaks, the gear will stop at the next tooth. Therefore, the order is gear > chain > belt in the aspect of reli- ability. In most cases: (1) An increase in gear noise indicates that the end of the service life is near. (2) You will know that the chain is almost at the end of its life by wear elongation or an increase in vibration caused by wear elongation. (3) It is difficult to detect toothed-belt life without stopping the machine and inspecting the belt carefully. It is possible to decrease gear noise by adjusting the gears precisely or by adapting the drive to a helical or double helical gear. Both of these are expen- sive, and thrust load may occur with the use of helical gears. Chain is more suitable to long-term continuous running and power trans- mission with limited torque fluctuation. Gears are more fit to reversing or intermittent drives. The greater the shaft center distance, the more practical the use of chain and belt, rather than gears.
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