1. Chain Basics
Table 1.1 Comparison Table Type
Roller Chain
Tooth Belt
V Belt
Spur Gear
Sychronization Transmission Efficiency Anti-Shock Noise/Vibration Surrounding Condition
Avoid Water, Dust
Avoid Heat, Oil, Water, Dust Avoid Heat, Oil, Water, Dust
Avoid Water, Dust
High Speed Low Load Low Speed High Load Compact
Space Saving
Heavy Pulley
Wider Pulley
Less Durability Due to Less Engagement
Lubrication
Required
No Lube
No Lube
Required
Layout Flexibilty Excess Load onto Bearing
Excellent
Good
Fair
Poor
Generally, under the same transmission conditions, the cost of toothed belts and pulleys is much higher than the cost of chains and sprockets. See the following features and points of notice about roller chain transmission. Features of Chain Drives: 1.Speed reduction/increase of up to seven to one can be easily accommodated. 2.Chain can accommodate long shaft-center distances (less than 4 m), and is more versatile. 3.It is possible to use chain with multiple shafts or drives with both sides of the chain. 4.Standardization of chains under the American National Standards Institute (ANSI), the International Standardization Organization (ISO), and the Japanese Industrial Standards (JIS) allow ease of selection. 5.It is easy to cut and connect chains. 6.The sprocket diameter for a chain system may be smaller than a belt pulley, while transmitting the same torque. 7.Sprockets are subject to less wear than gears because sprockets distribute the loading over their many teeth. Points of Notice: 1.Chain has a speed variation, called chordal action, which is caused by the polygonal effect of the sprockets. 2.Chain needs lubrication. 3.Chain wears and elongates. 4.Chain is weak when subjected to loads from the side. It needs proper alignment. 7
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