Prefabricated metering valve between the process, according to the condition of the structure, characteristics and possible causes deformation produced

During the welding process , the structure is subjected to uneven heating and cooling , the metal parts of different degrees of expansion and contraction . Metallic material as a whole, interrelated, mutual restraint, elongation and shortening are not free , so the welding process will produce stress and deformation . Welding deformation leads to the size and shape of the weldment changes directly affect the manufacturing quality . If the distortion exceeds the normal range , you need to rework correction processing , reduce work efficiency, but also increase the cost of production. Between the metering valve prefabricated process, depending on the situation should be carefully analyzed its structure ,  Stainless steel needle valve  and possible causes deformation , select a reasonable measures to control the deformation process , meet the technical standards in order to improve the effectiveness and reduce unnecessary losses . When the valve between the measured deformation reason prefabricated , conducted at the Department of  Instrument valve manifolds  tube cutting and welding are localized uneven heating process . Cutting and welding , thermal expansion of the high temperature region , hindered by the rigidity of the surrounding area and can not freely low elongation , resulting thermoplastic deformation. Upon cooling, the high-temperature region due to shrinkage of the thermoplastic deformation of the large amount of shrinkage in a low temperature region is small, this causes uneven shrinkage generated manifolds condensed bending.