A double welded seam welded integral forged steel piston

Abstract

The invention relates to a double seam welded integral forged steel piston. It consists of a piston head and a piston skirt made of forged steel. The piston head is located in the concave cavity. The outer circle of the end face with a large diameter of the piston head is welded The top surface of the outer circle part of the end face forms the first single-sided weld, and the inner circle part of the end face with the small diameter of the piston head is welded with the outer wall of the boss at the bottom of the cavity, and the inside of the end face with the small diameter of the piston head The top surface of the circular part forms a second single-sided weld, and a gas ring groove and an oil ring groove are sequentially arranged on the peripheral wall of the upper part of the piston skirt from top to bottom. The piston head of the present invention is arranged in the concave cavity on the top of the piston skirt and welded together, the piston head and the piston skirt are firmly connected, and there will be no "top off" phenomenon, and the welding seam is outside the cooling oil chamber, which is easy to clean , avoiding the hard particles of the weld from falling off and causing the engine to scuff.

Description

technical field [0001] The invention relates to a double seam welded integral forged steel piston. Background technique [0002] The piston is the "heart" of the automobile engine, which bears alternating mechanical loads and thermal loads, and is one of the key components in the engine with the worst working conditions. The function of the piston is to withstand the gas pressure, and transmit it to the connecting rod through the piston pin to drive the crankshaft to rotate. The failure of the piston will cause the engine to lose power, and even cause the entire engine to be scrapped. [0003] In the past ten years, engine design and manufacturing technology have been rapidly improved, especially diesel engines are developing towards high power and high load, the degree of strengthening has been continuously improved, and the explosive power has exceeded 20MPa. Although the piston has the advantage of light weight, the aluminum alloy material can only work stably at 350°C. ...

AI Technical Summary

Problems solved by technology

[0004] In the existing technology, the forged piston head and the forged piston skirt are welded together by friction welding to manufacture the piston. This manufacturing method causes the weld seam inside the closed oil chamber to be unable to be cleaned. There are hard particles falling off, which increases the risk of engine scuffing

In addition, when friction welding the piston head and piston skirt, the welding machine and welding parameters are very demanding. Improper adjustment is prone to welding defects, which will lead to the separation of the piston head and piston skirt during use, resulting in engine damage. Even the scrapping of the entire locomotive

It is known that some domestic friction welding pistons have cracked welding parts many times, causing great losses. In addition, friction welding consumes a lot of electricity and wastes energy.

Images