With the continuous improvement of the requirements of aluminum piston manufacturers for increasing production and reducing consumption, aluminum piston manufacturers generally adopt the the first mock examination double cavity casting technology, and put forward higher requirements for the quality of aluminum piston the first mock examination double cavity casting. As a reciprocating part in the cylinder of an internal combustion engine, aluminum piston is prone to failure if its own structure is unreasonable, which directly affects the reliability of the engine. Because of this, people have strict requirements for the finished aluminum piston, such as the radial wall thickness difference of the skirt of the finished aluminum piston.
All aluminum piston manufacturers are looking forward to obtaining a mold component that can fundamentally solve the radial wall thickness difference of the skirt of the double-cavity casting aluminum piston blank. The purpose of this improved technology is to overcome the shortcomings of the original technology mentioned above, and to obtain a mold improvement technology that can fundamentally solve the radial wall thickness difference of the skirt of the double-cavity casting aluminum piston blank.
The casting efficiency of aluminum piston blanks produced by the first mock examination and two cavity mold components is twice that of the first mock examination and one cavity, and the loss of aluminum liquid in the casting system is half that of the first mock examination and one cavity. Therefore, the the first mock examination double cavity mold component structure has always been recognized as an excellent structure in the industry. The “the first mock examination with two cavities mold component” is composed of top mold, external mold I, external mold II, core mold I, core mold II, pin hole mold I, pin hole mold II, and seam locking fixed seat. The bayonet fixed seat is fixed on the operating platform, and the pin hole mold I and pin hole mold II are inserted into the pin hole of the external mold I and II respectively. The top mold, outer mold I, outer mold II and core mold are respectively pulled by the upper, left, right and lower CNC hydraulic traction mechanism installed on the operating platform and the platform. Through this traction, automatic combination and automatic separation and demoulding between mold components are realized. The outer mold I and the outer mold II are limited to move on the table top of the operating platform. When assembling the mold, the two are joined together, and the joint surface is the vertical parting surface.
In the splicing state, the two independent half cavities of the external mold I and the two independent half cavities of the external mold II are facing each other, forming two independent external mold cavities respectively. The filling ports of the two outer mold cavities face each other and are connected with each other through horizontal runner. The pouring mouth is located at the upper part of the horizontal runner, and is connected with the horizontal runner through the vertical tapered runner. A 2mm wide filling opening shall be opened at the place 4mm from the horizontal runner to the piston skirt. The sprue, vertical tapered sprue, horizontal sprue, and filling mouth are cut into two halves by the vertical parting surface. The the first mock examination double cavity external mold assembly refers to the two mold assemblies, namely, the external mold I and the external mold II.
After a year of practice, it has been proved that although the processing of this mold component is complex, cumbersome, and the process accuracy is required to be high, the problem of poor wall thickness of the cast aluminum piston blank caused by the thermal expansion of the external mold has been completely solved once and for all, the controllability of the casting aluminum piston blank process has been improved, the scrap rate has been reduced, and the yield has been improved. The single finished product rate of aluminum piston blank castings has increased from 72% to 98%, and the productivity has been greatly improved, while good economic benefits have also been achieved.