Pneumatic valve welding standard 1)

in petroleum, chemical industry, metallurgy and energy industry, one of the pneumatic valve is widely used in fluid control equipment. As a pipeline system, pneumatic valve, specifications and an important part of the role of many different types. Others are used to connect or disconnect the media, regulatory medium pressure or flow rate, prevent pressure exceeds the value of the media, to ensure the safety of the pipeline and equipment operation. Some of them are used to separate, assignment or mixed media, to ensure that the conditions of the system. Because the pipeline system of pneumatic valve, pneumatic valve manufacturing process function will directly affect the safe operation of the pipeline equipment. As a result, 'pressure piping components manufacturing safety registration and management approach', should be pneumatic valve manufacturing unit security register, only registered with the security of pneumatic valve manufacturing unit used in the production of pressure pipes.
due to the growing demand of labor conditions, pneumatic valve performance requirements more and more high, manufacturing process more and more attention. The pneumatic valve and pipeline related technical specification of incomplete components, such as pneumatic valve welding, corrosion resistance and wear surfacing welding surface is not clearly defined. The particularity of the pneumatic valve, can be manufactured in accordance with the relevant boiler pressure vessel, pressure piping specifications remains to be discussed, all of these safety pneumatic valve will be difficult to achieve the follow-up assessment. In this paper, the relevant problems in the development of the new standard is analyzed and the suggestion, increase according to actual needs of the corresponding contents, more comprehensive, more technical specification for easy operation.
large pneumatic valve commonly used in the manufacture of welding and the thickness of the wall are often larger than mm. The relevant regulations of the pressure vessel pressure pipes at home and abroad, in foreign countries when the thickness is greater than the mm, weldment is its thermal aging treatment after welding, the purpose of dehydrogenase, eliminating welding residual stress and plastic material recycling. However, due to the different seal material, and after welding heat aging can lead to deformation of the pneumatic valve, pneumatic valve is to heat treatment, or how to do to ensure that the relevant standards of quality in the country is not specified. At present, large foreign welding pneumatic valve has entered the Chinese market, by what criteria should accept or not and heat treatment after welding requirements of pneumatic valve is given priority to, also is worth discussion and research. So, for such a special product of large welding pneumatic valve, especially if it after welding heat aging, need to conduct a comprehensive test, the test including the welding groove, joint type, temperature control and eliminate the stress or stress deformation research, to determine welding joint, reliable performance, and formulate the corresponding standards, to ensure the quality and reliability of pneumatic valve.