Special casting of valves
Classification:
Release Time：2018-12-18
The basic principle of 1. low-pressure casting valve Low-pressure casting is to inject molten metal into a sealed resistance crucible furnace for heat preservation. The mold is placed on the sealing cover, and the vertical riser pipe makes the metal liquid communicate with the downward gate. The mold is horizontal parting, and the metal mold must be preheated before pouring and sprayed with paint. During die casting, the upper half of the mold is locked first, and the compressed air is slowly introduced into the crucible chamber so that the metal liquid is pressed into the mold through the riser tube. After the mold is filled, the air pressure is compressed to the specified working pressure, and the appropriate time is maintained to crystallize the alloy under pressure. Then, the pressure on the liquid surface is removed, so that the riser and the gate are still.
The basic principle of 1. low pressure casting valve
Low-pressure casting is to inject molten metal into a sealed resistance crucible furnace for heat preservation. The mold is placed on the sealing cover, and the vertical riser pipe makes the metal liquid communicate with the downward gate. The mold is horizontal parting, and the metal mold must be preheated before pouring and sprayed with paint.
During die casting, the upper half of the mold is locked first, and the compressed air is slowly introduced into the crucible chamber so that the metal liquid is pressed into the mold through the riser tube. After the mold is filled, the air pressure is compressed to the specified working pressure, and the appropriate time is maintained to crystallize the alloy under pressure. Then, the pressure on the liquid surface is removed, so that the liquid metal that has not yet solidified in the riser and gate flows back to the crucible under the action of gravity. Finally, open the mold and remove the casting. Due to the low pressure casting when the gate also plays the role of feeding, in order to achieve top-down directional solidification of the casting, the gate should be opened at the thick wall of the casting, and the cross-sectional area of the gate must also be large enough.
Characteristics and scope of application of 2. low-pressure casting valves
Low pressure casting has the following characteristics:
(1) The filling pressure and filling speed are easy to control, so it can be adapted to various casting molds, such as metal mold, sand mold, molten model shell, tree-shaped shell, etc. Because the filling is stable, the scouring force is small, and the direction of liquid flow and air flow is consistent, defects such as pores and slag inclusions are reduced.
(2) The casting organization is denser than sand casting, and the effect of preventing pinhole defects in aluminum alloy castings is particularly obvious.
(3) due to eliminating the feeding riser, the utilization rate of metal is increased to 90% ~ 98%.
(4) Due to the improved filling capacity, it is conducive to the formation of castings with clear contours and smooth surfaces.
Previous Page
Next Page
Related News
2026/02/28
Contact Information
+86 27-8970 8339
Address: No.5, Zhengjie, Shuangliu Street, Xinzhou District, Wuhan City, Hubei Province