scope:

This Practice describes guidelines for selecting non-lubricated flexible couplings for general purpose applications for most types of rotating equipment. General purpose coupling applications include loads with steady, non-fluctuating torque characteristics within the power and speed ranges defined in this Practice.

This Practice does not include guidelines for diaphragm couplings.

This Practice does not cover coupling applications for rotating equipment having any of the following characteristics:

a. Rotational speeds greater than 3,600 rpm

b. Driver-rated power greater than 2,000 horsepower

c. Non-steady (fluctuating) torque characteristic

d. Couplings covered by API 671, Special Purpose Couplings for Petroleum, Chemical and Gas Industry Services