center drilling

Drilling of a conical hole in the end of a workpiece to support it while being rotated. A ‘center drill’ is used.

Coupling flywheel effect (Polar weight moment of inertia)

A measure of the potential of the coupling to resist change in speed equal to the product of the weight of the coupling times the square of the radius of gyration (WR^2). The radius of gyration is the radius at which the mass of the part (coupling) can be considered concentrated.

Coupling rated speed

The maximum speed at which the coupling is capable of transmitting the coupling continuous rated torque while being simultaneously subjected to the rated angular misalignment and the coupling rated axial displacement.

Crown diameter

The major diameter of the external gear teeth.

Center of gravity

For a half-coupling, the location at which the weight of that half-coupling can be considered to be concentrated. The half-coupling’s effective center of gravity is referenced from the equipment shaft end, with a positive location being beyond the shaft end and a negative location being within the shaft.

Chain coupling

A coupling that consists of two hubs with sprocket teeth that engage or mesh with a strand of chain.

Clearance-fit bore

A bore with a hub bore diameter equal to or larger than the shaft diameter

Continuously-lubricated gear coupling

A coupling designed to be lubricated by a continuous external supply of oil directed at or into the gear mesh.

Coupling mass simulator

An auxiliary device designed to correctly simulate both the effective mass and the effective location of the center of mass of a half-coupling with respect to the shaft on which it is mounted.

Core - Heat Treating

In a ferrous alloy prepared for case hardening , that portion of the alloy that is not part of the case . Typically considered to be the portion that (a) appears light on an etched cross section, (b) has an essentially unaltered chemical composition, or (c) has a hardness, after hardening, less than a specified value.