Lost-wax casting technology for thin-wall pressure-bearing casting

Abstract

The invention discloses a lost-wax casting technology for a thin-wall pressure-bearing casting. The lost-wax casting technology comprises the following steps of according to technology design requirements, placing patches on an inner cavity of an air cylinder casting from bottom to top by employing a hot spot incircle rolling method, changing an iso-wall thickness structure of the air cylinder casting into a structure which is gradually thickened from bottom to top, thus being in favor of forming progressive solidification, designing two risers at the thickest part of an upper part patch of the air cylinder casting, making the risers perform feeding on the thickest part, placing a riser neck at a hot spot position of the air cylinder casting, determining the risers and a gate stick according to the size of the riser neck, and then, manufacturing a mold according to the technology requirement; molding: opening the mold, checking whether a mold cavity is intact or clean or not, sprayinga mold releasing agent to a position comparatively tiny and complicated in shape in the mold cavity, then, injecting wax into the mold cavity by utilizing a wax injector, after wax injection is finished, opening the mold after a wax piece is cooled, and taking out a wax mold. The lost-wax casting technology disclosed by the invention is capable of increasing quality of the casting and reducing casting defects.

Description

technical field [0001] The invention relates to the technical field of casting, in particular to a thin-wall pressure-bearing casting wax mold casting process. Background technique [0002] Pneumatic actuators are used in actuators that drive the opening and closing or regulating valves by air pressure. They are widely used in power plants, chemical industry, oil refining and other fields. They have the characteristics of large torque, small space and curved torque. The cylinder, the key component of the piston pneumatic actuator, is required to have the characteristics of pressure bearing, no leakage, and wear resistance. Therefore, the cylinder castings of the pneumatic actuator are not allowed to have casting defects such as air holes, shrinkage cavities, shrinkage porosity, and slag inclusions. At present, the low-temperature wax investment casting process is used for cylinder castings. The investment casting process has the advantages of high dimensional accuracy and lo...

AI Technical Summary

Problems solved by technology

At present, the low-temperature wax investment casting process is used for cylinder castings. The investment casting process has the advantages of high dimensional accuracy and low surface roughness. However, castings with this structure are prone to shrinkage defects, and dispersion may appear on the inner surface of the cylinder after machining. Add locally concentrated black spots, which will reduce air tightness and damage the piston