Basics
6. Center distance between sprockets. 7. Noise constraints. 8. Lubrication (possible or not).
4.1.2 Coefficients Used in Selection 1. Multiple strand factor
In multiple strand power transmission chains, the loading is unequal across the width of the chain, therefore, the transmission capability is not a direct multiple of the number of chains. You must use a “multiple strand factor,” which is shown in Table 4.1, to determine the correct value. 2. Service factor, Ks The chain transmission capability is reduced if there are frequent or severe load fluctuations. You must apply the appropriate factor based on the type of machine or motors (Table 4.2).
Table 4.1 Multiple Strand Factor
Number of
Multiple
Roller Chain Strands
Strand Factor
2 3 4 5 6
1.7 2.5 3.3 3.9 4.6
Table 4.2 Service Factor
Source of Power
Internal Combustion Engine
Electric Without Motor or Hydraulic Hydraulic With
Type of Impact Machines
Turbine
Drive
Drive
Smooth
Belt conveyors with small load fluctuation, chain conveyors, centrifugal blowers, ordinary textile machines, ordinary machines with small load fluctuation. Centrifugal compressors, marine engines, conveyors with some load fluctuation, automatic furnaces, dryers, pulverizers, general machine tools, compressors, general work machines, general paper mills. Press, construction or mining machines, vibration machines, oil-well rigs, rubber mixers, rolls, general machines with reverse or high-impact loads.
1.0
1.0
1.2
Some impact
1.3
1.2
1.4
High impact
1.5
1.4
1.7
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