Copper pneumatic valve fault judgment and solving methods

copper pneumatic valves, pneumatic valves used in fluid control, from the most brief stop pneumatic valve to extremely complex automatic control system used in all kinds of pneumatic valves, the type and standard of heavy and complicated, nominal size of the pneumatic valve from microscopic appearance of pneumatic valve to the size of m industrial piping with pneumatic valve faults treatment, but using a period of time will need to overcome obstacles and questions. Timely replacement and repair in order to better use.
and disadvantages discriminant in produce practice, some of the casting defects are not allowed to repair welding, such as perfoliate crack, penetrating faults ( Wear bottom, honeycomb pores, can't erase the sand inclusion of slag and the area beyond the px shrinkage and so on, and on both sides in the contract about good other can't repair welding of the serious shortcomings. Before the repair welding should distinguish the drawback of the type.
and disadvantages away in factories usually can use carbon arc air gouging blow to the casting defects, and then with a portable Angle grinder grinding defects parts to show metallic luster. But produce practice is more directly with carbon steel electrode large current get rid of faults, and grinder grinding the metallic luster. Usually casting defects, available & lt; mm - J electrode, to A current, the faults in addition to clean, burnish of faults mouth Angle grinder into U, reduce welding stress. Faults to remove completely, repair welding quality is good.
and disadvantages 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, usually without preheating. But ZGCrMoV, ZGCrMo pearlitic steel casting, because the steel hardening tendency is big, 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. Not all the preheating, such as casting - 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 at faults and the surrounding do circular agile first swing for a few minutes, and then to the slow moving min ( Depending on the thickness of defect, make the weakness part of energetic after preheating, agile repair welding.