CN102744356B - Full-fiber bending-upsetting method for crank shaft - Google Patents

Abstract

The invention discloses a full-fiber bending-upsetting method for a crank shaft, comprising the following steps of: firstly, using an upsetting device to pre-form a round bar; upsetting to form a second crank throw, and forming a complete third crank web and a semi-finished second crank web after the finish forging of the second crank throw; upsetting to form a first crank throw, and completely upsetting to form a second crank web and a first crank web after the final forging of the first crank throw; repeating the steps until the forging of the whole crank shaft is completed by upsetting the crank throws one by one; and finally, machining the obtained crank shaft in accordance with a design drawing to obtain a finished crank shaft. By using the full-fiber bending-upsetting method for the crank shaft, the upset crank shaft has a rough shape structure, and the machining allowance reserved for the subsequent machining is reduced, so that the processing cycle is shortened, and the processing cost is saved; and the material utilization rate is improved over 55%, so that a large amount of material cost can be saved.

Description

Bent axle Whole fiber bending and upsetting method

Technical field

The invention belongs to metal forming technique in material processing, particularly relate to a kind of Whole fiber bending and upsetting method of large-scale compressor bent axle.

Background technology

As shown in Figure 1, large-scale compressor bent axle and traditional locomotive, ship machine crankshaft make a big difference, and one is that between crank throw, angular distribution is irregular; Two is that crank shape is strange; Three is that crank thickness and appearance and size differ greatly.At present, the typical Forging Technology of large-scale compression machine crankshaft both domestic and external is flat-die forging, steel ingot upsetting is become round bar, is then completed the processing of whole bent axle by machined.The shortcoming of this technique is: 1, cost is high, and stock utilization is low, lower than 30%; 2, surplus is excessive causes the machined cycle long, and an open die forging crankshaft forging roughing operation needs more than 2 months.

Summary of the invention

It is high that object of the present invention is just to provide a kind of stock utilization, the bent axle Whole fiber bending and upsetting method that the process-cycle is short, can solve the problems of the technologies described above completely.

Object of the present invention is realized by following technical proposals:

A kind of bent axle Whole fiber bending and upsetting method, comprises the following steps:

A. round bar carries out blocking;

B. upsetting is shaped the second crank throw, and after the second crank throw finish-forging completes, the 3rd crank arm is fully formed, and the second crank arm becomes half form state;

C. upsetting is shaped the first crank throw, and after the first crank throw finish-forging completes, the second crank arm and the complete upsetting of the first crank arm are shaped;

D. circulate above-mentioned steps, and crank throw upsetting completes the forging of whole bent axle one by one;

E. according to design drawing, machined is carried out to the bent axle forged, obtain bent axle finished product.

Further, described round bar is the round bar utilizing upsetting apparatus steel ingot upsetting to be formed.

Compared with prior art, beneficial effect of the present invention is:

Easy and simple to handle, practical, upsetting dies for crankshafts is used in upsetting process, crankshaft forging after upsetting has the shape and structure close with bent axle finished product appearance profile, reduce as the reserved allowance of follow-up machined, thus shorten the process-cycle, saved processing charges, stock utilization significantly improves, reach more than 55%, save lot of materials expense.And adopt Whole fiber bending and upsetting method, bent axle metallic fiber is continuous, and bent axle comprehensive mechanical performance, fatigue strength and safety coefficient improve all greatly.Facts have proved, bending and upsetting method improves 20% compared with the fatigue strength of flat-die forging bent axle, saves metal 40-60% simultaneously, reduces allowance, can save machining man-hour about 1/3, improve safety coefficient 19%.

Accompanying drawing explanation

Fig. 1 is the schematic diagram to round bar blocking in the present invention;

Fig. 2 is allowance schematic diagram of the present invention;

Fig. 3 is the schematic diagram of the second crank throw of being shaped in the present invention;

Fig. 4 is that the present invention is shaped the state diagram of bent axle after the second crank throw;

Fig. 5 is the schematic diagram of the first crank throw of being shaped in the present invention;

Fig. 6 is the crankshaft structure schematic diagram through each step postforming of the present invention.

Detailed description of the invention

Below in conjunction with specific embodiments and the drawings, the present invention is further illustrated.

As shown in Figures 1 to 6, a kind of bent axle Whole fiber bending and upsetting method, comprises the following steps:

A. utilize upsetting apparatus that steel ingot upsetting is formed round bar, blocking is carried out to round bar, as shown in Figure 1; According to compressor crank shaft finished figure design forging drawing, when the forging drawing of design second crank arm A, need to take into full account the crank arm circumference size of surplus and the reasonable increase of remaining block according to the feature of bending and upsetting method, as shown in Figure 2.

B. as shown in Figure 3 and Figure 4, upsetting is shaped the second crank throw A, and after the second crank throw A finish-forging completes, the 3rd crank arm 3 is fully formed, the second crank arm 2 one-tenth half form state;

C. as shown in Figure 5, upsetting is shaped the first crank throw B, and after the first crank throw B finish-forging completes, the second crank arm 2 and the first crank arm 1 completely upsetting are shaped;

D. as shown in Figure 6, circulation above-mentioned steps, crank throw upsetting completes the forging of whole bent axle one by one;

E. according to design drawing, machined is carried out to the bent axle forged, obtain bent axle finished product.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.

Claims (2)

1. a bent axle Whole fiber bending and upsetting method, is characterized in that, comprise the following steps:

A. round bar carries out blocking;

B. upsetting is shaped the second crank throw, and after the second crank throw finish-forging completes, the 3rd crank arm is fully formed, and the second crank arm becomes half form state;

C. upsetting is shaped the first crank throw, and after the first crank throw finish-forging completes, the second crank arm and the complete upsetting of the first crank arm are shaped;

D. circulate above-mentioned steps, and crank throw upsetting completes the forging of whole bent axle one by one, and this bent axle has the not identical crank arm of three shapes, and has different angles between crank arm, and the radius of gyration of connecting rod neck is not identical;

E. according to design drawing, machined is carried out to the bent axle forged, obtain bent axle finished product.

2. bent axle Whole fiber bending and upsetting method according to claim 1, is characterized in that: described round bar is the round bar utilizing upsetting apparatus steel ingot upsetting to be formed.