1) high pressure pneumatic valve oil briefly process improvement

wellhead equipment, Christmas (dosage the biggest, Tree) Is a special kind of oil and gas valve, pneumatic valve in the pneumatic valve manufacturing process, sealing water pressure strength test and performance test qualified rate is too low ( % and %) Long, long plagued manufacturing factory. In this article, the practical production of our factory the crux of the problem are analyzed, and solutions are put forward.
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blank casting process improvement our factory often internally threaded hole, the casting defects such as shrinkage cavity wellhead pneumatic valve with sand casting, rough process, cooperation with the pneumatic valve seat body, main part of macro analysis found that, in the hot area, there are different levels of contraction phenomenon, in order to solve the above problems, we made some improvement of casting process test.
) Improved water riser system. Will set the water riser system on both sides of the cylinder, Settings as shown in the body at the bottom of the sprue system cross;
) Change the investment casting sand mold casting;
) Changed water pouring method at the top of the end, and make the flange. Casting sand mold casting than has better ventilation, faster, more uniform cooling conditions, make the organization more dense. Molten steel into from the top, but also from directly to near the hot area of water the riser casting riser. For actors to create a very favorable solidification conditions, hot fields get timely feeding, therefore, the process improved the casting of intensive production, to eliminate the casting defects such as shrinkage, product qualification rate reached %.
, the measures to improve the production and processing accuracy
the key factor for sealing effect of pneumatic valve manufacturer. Sealing problems has been difficult to solve the problems of the mechanical processing industry, improve the manufacturing accuracy, pneumatic valve sealing, to ensure that through theoretical research and production practice, summarized the following improvement.
pneumatic valve body is the most critical part, because of the requirement of production structure, pneumatic valve seat sealing surface and center symmetry plane tilt? 吗? o。 For small pneumatic valve body, we use the auxiliary bending horizontal lathe tool ( See the figure) Complete seat inclined plane processing. But we must ensure that the bending Angle ( 吗? 吗? o) With the human body is consistent with the requirements. At the same time, should be strictly ensure the center of the bending die with high overlapping machine center. Tolerance is. 毫米吗? 。 Between the control of mm. In addition, in the process of the pneumatic valve should be considered when press this, positioning accuracy and reliability. As shown in figure, should be turned to face a frame of reference, the weight of the main shaft bending of the wedge-shaped plate and slot wedge sliding surface using vertical will find that the body pressure at one end flange, handled separately on both sides. In addition, in the process of the body, need to rely on to return to the lathe processing cavity rotating wheel to complete a degree of finish on both ends. The rotation accuracy is made up of two symmetrical distribution of tapered flange positioning repeat positioning pin hole, to ensure that in turn. Transposition in error. 毫米吗? 。 Mm. Lining butterfly pneumatic valve
in addition, to choose the right weight and bent plate. As is known to all, a direct impact on the static balance of bending die lathe precision lathe and the production efficiency, make our shape and weight of the layout of the bending plate up a great deal of effort, a radius of gyration is to try to reduce weight, the second is on the inside the cylinder structure, improving the layout of the balance of the circumferential direction, to maximize the speed of the machine and machining precision of workpiece.
in the end, in order to ensure the coordination between the parts of sealing process:
the body and the consistency of the fitness; Pneumatic valve slope and the consistency of the bending; Doors and bend with the consistency of the slope plate; Door and ground slope of Taiwan's consistency.
the consistency between the four interrelated constraints, depend on each other. Consistency of four, we are turning to bending slope, on the basis of repeated screening, grinding out the standard gradient plate, in turn, and then use grinding lathe processing good consistency gradient plate four control standard gradient, increase productivity, assembly accuracy can be guaranteed.
in addition, the seat should be in the grinding process control, to ensure that no less than:. Seat surface roughness is to ensure effective, from scratch, knock against, inequality, and other factors of the sand grinding surface roughness degree, after grinding to implementation, to ensure the accuracy of the pneumatic valve seat best results.
by effective measures and quality control, the pneumatic valve series of now our factory production wellhead qualified rate of more than %.