Half-die forging method and device for large-scale marine crank throw

Abstract

The invention discloses a half die forging method and a half die forging device of a crank throw for a large ship. The half die forging method includes the flowing steps: removing the head portion and the tail portion of a steel ingot, forging and pressing the steel ingot to a flat billet with a boss in the middle of the flat billet, conducting lateral press at the same time to the boss of a pre-formed blank by using two symmetrical side press clamp round models, clamping a round part of a pin part, embedding and pressing the blank after the blank is laterally pressed by using a bend forging upper die and a crank throw pin part forming die, bending forging, and conducting secondary bending forging and repair by using an upper flat anvil and a lower flat anvil. The side press clamp round models is are used for replacing an existing V-shaped die, and the crank throw pin part forming die is added, the shape of a crank throw pin part after half die forging is close to a circle, slopes of two sides are formed at the same time, and subsequent processing time is reduced, optimal design of boundary dimension of the blank and parameters of the die are conducted by using a computer analog technology, test times and capital investment are reduced, working allowance of forging pieces after optimization is reduced obviously, production raw material and costs are saved and production efficiency is improved.

Description

technical field [0001] The invention belongs to the field of forging, in particular to a half-die forging method and device for a large-scale marine crank throw. The device and process are obtained by computer simulation technology and are suitable for manufacturing large-scale marine crank throw forgings. Background technique [0002] Crankshaft (also known as crank arm, crankshaft or crank) is an important part of large and medium-sized marine diesel engines, mainly used for crankshafts in large and medium-sized marine diesel engines (over 10,000 tons) and low-speed two-stroke diesel engines for power generation. According to the production method, it can be divided into forging and casting, and according to the structure, it can be divided into integral type and combined type (combined, semi-combined). Combined production is adopted, and the difficulty of forging the combined crank throw lies in the forging of the crank throw. [0003] At present, the main method of manu...

AI Technical Summary

Problems solved by technology

[0004] However, due to the limitation of the mold, the crank pin has a large residual block, which not only increases the smelting cost of raw materials, but also consumes a lot of unnecessary processing man-hours, prolongs the production cycle, and is not conducive to the mass production of crankshafts.

The traditional V-pressing method of the crank arm is mainly to avoid the formation of folds due to local material accumulation, which does not significantly reduce the margin of precision forging.

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