Friction factor of spiral welded pipe

Spiral welded pipe friction adhesion theory is now widely accepted, in the static friction, the actual contact area is proportional to the load. And when the sliding friction, we must consider the presence of shear force, then, increasing spiral steel actual contact area results from the normal load and shear load to the combined effects of. It also can be said that the yield point of contact occurs, with the compressive stress caused by the normal load and the tangential load of the synthetic stress caused by the shear stress related.

When spiral welded pipe is friction in the air, there is a natural pollution due to surface membrane, it’s natural to use friction phenomenon contaminated film adhesion theories exist to explain the metal surface. In fact, most of the metal surface is always covered with a thin oxide film, and thus this friction to metal friction, the friction of the oxide film is essentially an oxide film, after destruction of the oxide film is only possible to directly form a metal-to-metal friction. When a low friction surface is contaminated, and the contamination of the membrane shear strength, adhesion junction growth is not obvious. When the spiral steel pipe when membrane fouling shear stress reaches the shear strength of pollution membrane surface film was cut, friction began to slide. In this case, the adhesive friction coefficient can be expressed as f = k / v where, for the shear strength of surface contamination film is the yield point of the metal body.


Post time: Aug-17-2021