Copper pneumatic valve defect judgment and solution

jiangsu copper pneumatic valves, and other functions, used for flow control of pneumatic valves, pneumatic valve from the simplest deadline to extremely complex control system used in all kinds of pneumatic valves, its breed and specification is various, pneumatic valve nominal diameter instrument pneumatic valve from very small to the size of m industrial pipeline defects with pneumatic valve processing, but the use of a period of time will need to overcome obstacles and problems. Replacement and repair in time in order to better use.
and defects in the production practice, some of the casting defects are not allowed to repair welding, such as perfoliate crack, penetrating defects ( Wear bottom, honeycomb pores, unable to remove the sand inclusion of slag and area of more than px shrinkage and so on, and the two sides agreed in the contract of other major defects can't repair welding. Before the repair welding should judge the type of defect.
, defect rejecting generally can be used in factories, carbon arc air gouging blow to the casting defects, and then use portable grinder grinding defects parts to show metallic luster. But more in the production practice is directly with carbon steel electrode current defect removal, and the Angle of grinding machine grinding out the metallic luster. Casting defects, commonly available & lt; mm - J electrode, to A current, A defect in addition to clean, burnish of defect mouth Angle grinder into U, reduce welding stress. Repair welding defect removal of the complete, good quality.
, defective parts preheating austenitic stainless steel castings, carbon steel and all the area of the repair welding parts & lt; Px, depth & lt; % or mm of thickness of castings, generally do not need to preheat. But ZGCrMoV, ZGCrMo pearlitic steel castings, such as, because of the large steel hardening tendency of cold welding crack easily, should make processing of preheating, preheat temperature for ~ ℃ ( Repair welding with stainless steel electrode, temperature of small value, heat preservation time should be no less than min. - such as casting cannot overall preheating, available oxygen Acetylene in the defect area and expand the mm after heated to - ℃( Back visual observation in the dark dark red, large cutting torch neutral flame gun rapidly oscillating in the defect and the surrounding is circular first for a few minutes, and then to move slowly to keep min ( Depending on the thickness of the defect, make the defective parts fully after preheating, rapid repair welding.