Acme Screw Load Definitions

Static Load

The maximum thrust load - including shock - that should be applied to a non-moving PowerAc™ Acme nut assembly. Actual maximum static load may be reduced based on end machining and screw mounting hardware.

Dynamic Load

The maximum recommended thrust load which should be applied to the PowerAc™ Acme screw and nut assembly while in motion.

PV Load

Any material which carries a sliding load is limited by heat buildup caused by friction. The factors that affect heat generation rate in an application are the pressure on the nut in pounds per square inch of contact area and the surface velocity in feet per minute at the major diameter. The product of these factors provides a measure of the severity of an application.

Tension Load

A load that tends to "stretch" the screw. (See Image 1 below)

Compression Load

A load that tends to "squeeze" the screw. (See Image 1 below)

Thrust Load

A load parallel to and concentric with the axis of the screw. (See Image 2 below)

Overturning Load

A load that tends to rotate the nut radially around the longitudinal axis of the screw. (See Image 2 below)

Side Load

A load that is applied radially to the nut.  (See Image 2 below)

IMAGE 1

 

IMAGE 2