In carbon steel erw pipe production process, as long as welding, pipe surface will cause stress and deformation, but to varying degrees Bale. Pipe welding stress and various modifications produced during welding, carbon steel erw pipe tends to decline in the quality of products, and even cause cracks. Welding deformation caused by the size, change the shape of the weldment, this change after more than a certain value, may not be connected or not enough allowance can not be cutting and other pipe. Let's say that under stress and deformation.
First, the surface stress of carbon steel erw pipe, when the material is not displaced under external force, its geometry and dimensions will change, this deformation is called strain. Deformation occurs when the material inside produces equal but opposite reaction against external forces, the distribution of internal forces at a point called the set of the stress, stress and micro-area product is the internal force, or object due to external factors (stress, temperature changes) and deformation between every part of the body's internal forces interact to resist the effects of such external factors, and try to make the object from the position after deformation response to the position before deformation.
From the mechanical point of view, to change the shape of the deformation refers to the structure (or a portion thereof). Any structure is made of a deformable solid material, will deform under external force and displacement.
In carbon steel erw pipe production process, even if we can redress, such as mechanical or flame straightening up, which is not only time consuming, but also adds additional stress welded pipes for building use negative, thus, we must welding stress and deformation the causes, extent, and how to reduce the size and avoid welding stress and deformation of understanding.