Stress and deformation of erw pipe

In the erw pipe production process, as long as the welding, erw pipe surface will have stress and deformation, but to varying degrees nothing more. ERW pipe in the welding process produced by the welding stress and a variety of deformation, often make the quality of welded products decline, and even cause cracks. Welding deformation caused by weld size, shape changes, such changes beyond a certain value may not be connected with other pipe or not enough machining allowance can not be cut. Below we say under the stress and deformation.

The first is the surface stress of the erw pipe, when the material can not produce displacement under the external force, its geometry and size will change, this deformation is called strain. When the material is deformed, its internal produces the same size but the opposite direction of the reaction force against external force, the distribution of internal force at a point of concentration is called stress, stress and micro-area product is the internal force, or object due to external factors (stress, temperature change, etc.) deformation, the internal forces in the interaction between the various parts of the body to resist the role of this external cause, and trying to make the object from the deformed position back to the pre-deformation position.

From a mechanistic point of view, deformation refers to the change in the shape of the structure (or a portion thereof). Any structure is made of a deformable solid material that will deform and displace under external forces. In the pipe production process, even if can be corrected, such as mechanical or flame correction, it is not only time-consuming and labor-saving, but also increases the additional stress erw pipe, the construction of the use of negative. Thus, we must understand the welding stress and deformation causes, size and how to reduce and avoid welding stress and deformation.