How to Model the Hold Down Clamp

Read about START-PROF pipe stress analysis software

 

If the clamp does not press the pipe to the base, but only limits its movement across horizontal and vertical lateral direction, then such restraint can be modeled using double-acting guide support. In this case, the friction force along the axis of the pipe F will be caused by friction on the vertical and lateral surfaces. The friction force is equal to:

F = Rym * μ + Rzm * μ,

Where

Rym - lateral load on the clamp

Rzm - vertical load on the clamp

µ - coefficient of friction

If the clamp is tightened and creates additional pressing force on the pipe, then additional vertical force Fp should be added to double-acting guide support. It is pre-load produced by the clamp tightening. In this case, the friction force along the axis of the pipe F will be equal to:

F = Rym * μ + Rzm * μ + Fp * μ,