Basics
Therefore, the chain design tension: F'b = Fb 3 Kv 3 Kc 3 Ku = 42.9 3 1.02 3 1.28 3 0.6 = 33.6 kN
When comparing the calculated chain tensions in Steps 2, 3, and 4, note that F'b in Step 4 is the greatest. In this tension, Ku is already counted. Comparing F’b with the maximum allowable tension of SUPER 120 chain, F'b < 39.2 kN. Therefore, this chain may be selected. The example shown above is for chain in hanging drives. The maximum ten- sion on the wrapping transmission chains is: F'b 3 d / d' = 33.6 3 171.22 / 303.75 = 18.9 kN
This value is less than the maximum allowable tension of SUPER 100 chain, which is 30.4 kN. Therefore, this chain is acceptable.
Other Important Considerations NOTE 1: If there are laws or regulations for chain selection, you must take them into account. For example, if the safety guideline says, “Safety factor must be greater than 10:1 compared with the minimum tensile strength,” then you should design the equipment as shown above, and consider the following: For hanging drive chain: Minimum tensile strength =M 3 g 3 Ku 3 10 = 3,000 3 (9.80665 3 10 -3 ) 3 0.6 3 10 = 176.5 kN But the minimum tensile strength of SUPER 120 chain is only 124.6 kN, which is not enough to meet this requirement. Instead, select SUPER 140 chain (213 kN). Wrapping transmission chain requires more than 99.5 kN of minimum tensile strength, therefore you may select SUPER 100 chain (111 kN). Regulations are not always safer than manufacturer’s suggested selection pro- cedure. Choose the safest system possible. NOTE 2: If a load greater than the motor braking torque very 48 occasionally occurs, the chains will be subjected to the following loads: Wrapping transmission chain: Fd = 0.096 3 1,000 3 60 3 2 3 0.6 = 48.4 kN 142.68 Hanging drive chain: 48.4 3 303.75 = 85.9 kN 171.22 To avoid chain plastic deformation, the minimum tensile strength must be more than twice these loads (see Basics Section 2.1.1), therefore, you should select SUPER 100 chain and SUPER 160 chain.
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