CN102581210B

CN102581210B - Forging method for thermoforming cylindrical forging by using hollow casting blank

Info

Publication number: CN102581210B
Application number: CN201210021315.5A
Authority: CN
Inventors: 安红萍; 武建国; 刘建生; 田香菊
Original assignee: Taiyuan University of Science and Technology
Current assignee: Taiyuan University of Science and Technology
Priority date: 2012-01-12
Filing date: 2012-01-12
Publication date: 2014-03-12
Anticipated expiration: 2032-01-12
Also published as: CN102581210A

Abstract

A forging method for thermoforming a cylindrical forging by using a hollow casting blank belongs to the technical field of the thermoforming of large-scale cylindrical forgings. The method is characterized by machining the hollow centrifugally casting blank prepared by centrifugally casting for removing defects on a surface layer of an inner hole, heating, placing in a set upsetting die and performing upsetting to reach a set height, reheating, placing in an expanding-extrusion die and performing expanding-extrusion composite deformation, reheating the deformed blank, and placing in a set backward extrusion die and performing backward extrusion deformation to achieve requirements of a finished forging. The forging method disclosed by the invention has advantages that the raw materials are saved; by forming inside dies, deformation is uniform, the forging is regular in shape, and the material is in the state of three-dimensional compressive stress, so that the cracking can be prevented and the performances can be improved; and during the deformation, the maximal deformed area in the blank is located in the inner hole of the blank, so that the shortcoming of serious looseness of the inner hole of the centrifugally casting blank is effectively compensated and the material uniformity is improved. Compared with the prior art, the forging method disclosed by the invention has remarkable effects of saving raw materials and improving product quality.

Description

Adopt the forging method of hollow casting blank thermoforming cylindrical

Technical field

The invention belongs to large annular barrel part hot forming technical field, be specifically related to a kind of forging method that adopts hollow casting blank thermoforming cylindrical.

Technical background

At present, the method for forging large annular barrel part is both at home and abroad mainly to adopt solid blanks, forms ring base after heating, jumping-up, punching, then by core bar drawing or saddle forging to corresponding size.The shortcoming of this forging method is that 1. technological process is tediously long, fire is inferior too much, it is inhomogeneous to be out of shape, easily produce additional stress causes forge crack; 2. solid blanks center material, as waste disposal in punching operation, causes waste of material, energy consumption to increase.

Summary of the invention

The present invention seeks to propose a kind of forging method that adopts hollow casting blank thermoforming cylindrical, can effectively overcome the shortcoming of prior art.

The present invention is achieved in that and it is characterized in that the hollow casting blank of centrifugal casting first by machined, to remove the defect on endoporus top layer, after being heated again the jumping-up of setting with mould in Upsetting reach setting height, melt down again after heating, the expansion that is placed on setting is squeezed with expanding crowded distortion in mould, after again the blank after the crowded distortion of expansion being reheated, be placed on the backward extrusion of setting with carrying out backward extrusion distortion in mould, reach forging requirement size.

Concrete operation step is:

1. by the endoporus of the hollow casting blank of centrifugal casting, by machined, remove the defect layer of 8-10mm;

2. jumping-up is placed on press platform with cylinder mould together with the jumping-up being assembled together with it with drain cap, hollow casting blank after heating is placed on to jumping-up uses the inside jumping-up of cylinder mould with on drain cap, again jumping-up is placed on hollow casting blank with T-shape anvil, starting press uses T-shape anvil to exert pressure while flushing with the upper end of cylinder mould with the upper surface of T-shape anvil and jumping-up to jumping-up and stop exerting pressure hollow casting blank by jumping-up, at jumping-up, place cushion block above with T-shape anvil, again starting press continues to exert pressure to hollow casting blank with T-shape anvil by cushion block and jumping-up, until hollow casting blank reaches the height of setting, obtain the blank after jumping-up,

3. the lower positioning table that upper end is equipped with to backstay is placed in and expands the centre bore squeezing with drain cap, said apparatus is positioned on press platform, after being reheated, blank after jumping-up is placed on lower positioning table, press is gently depressed, blank after jumping-up is fully contacted with lower positioning table, realize the centering of the blank after jumping-up, location, press lifts, expansion is squeezed to be loaded on to expand with cylinder die sleeve and squeeze with on drain cap, the expansion that center is had to a locating hole is squeezed and to be placed on above the blank after jumping-up with drift, and lower backstay is inserted and expand crowded using in the locating hole of drift, hollow cushion block is placed in to expand and squeezes with above drift, start press, by hollow cushion block with expand to squeeze the blank after to jumping-up with drift and exert pressure, until expand, squeeze the height that reaches setting with the lower surface of drift, after more lower positioning table being removed together with the backstay on it, restart press by the hollow cushion block that installs additional and expand and squeeze the blank after to jumping-up with drift and exert pressure, complete to expand and push through journey, obtain expanding the blank after squeezing, wherein descend positioning table and expand and squeeze by the shape of drift according to technique initialization,

4. backward extrusion is placed on press platform with cylinder mould together with the backward extrusion of laying on it with drain cap, after reheating, puts on backward extrusion cylinder mould backward extrusion drain cap blank after expansion is squeezed, backward extrusion is placed on above the blank expanding after squeezing with drift, and cushion block is placed on to backward extrusion with above drift, starting press exerts pressure to the blank expanding after squeezing with drift by cushion block and backward extrusion, complete backward extrusion whole deformation process, obtain the forging being shaped, wherein the number of cushion block is according to technique initialization.

Advantage of the present invention and good effect are:

1, adopt hollow casting blank to be shaped, in forging process, without punched scrap, produce, effectively improved stock utilization.

2, compare with traditional free forging process, owing to having adopted mould internal shaping, evenly, forging shape is regular in distortion, and forming process and product quality are easy to control.In deformation process, the most of region of blank, in three-dimensional compressive stress state, can effectively prevent the generation of forge crack, can forge again most of genetic defects in alloying base, obtains compact tissue.

3, in mould, jumping-up, expansion are squeezed blank inside in composite deformation process and all can be produced detrusion, make original coarse-grain fully broken, are conducive to crystal grain thinning, improve performance.

4, the interior maximum distortion of blank district is positioned at the endoporus place of strand, has effectively made up the poorest shortcoming of centrifugal strand endoporus quality, has improved the uniformity of material.

Accompanying drawing explanation

Fig. 1 is that hollow casting blank carries out the structural representation of Upsetting in enclosed heading die, and left side is schematic diagram before jumping-up, and right-hand part is schematic diagram after jumping-up.

Fig. 2 is that blank expands the crowded schematic diagram being out of shape in expanding extruding mold, and left side is out of shape front schematic diagram for expanding to squeeze, and right-hand part is out of shape schematic diagram midway for expanding to squeeze.

Fig. 3 squeezes distortion end of a period schematic diagram for expanding.

Fig. 4 blank carries out the schematic diagram of backward extrusion distortion in backward extruding die, and left side is the schematic diagram before backward extrusion distortion, and right-hand part is backward extrusion end of a period schematic diagram.

The specific embodiment

1. by the endoporus of the hollow casting blank of centrifugal casting 3, by machined, remove the defect layer of 8-10mm;

2. as shown in Figure 1, jumping-up is placed on press platform with cylinder mould 2 together with the jumping-up being assembled together with it with drain cap 1, hollow casting blank 3 after heating is placed on to jumping-up to be used on drain cap 1 with the inside jumping-up of cylinder mould 2, again jumping-up is placed on hollow casting blank 3 with T-shape anvil 4, start when press is used 4 pairs of hollow casting blanks 3 of T-shape anvil to exert pressure to flush with the upper end of cylinder mould 2 with the upper surface of T-shape anvil 4 and jumping-up to jumping-up by jumping-up and stop exerting pressure, at jumping-up, place cushion block 5 above with T-shape anvil 4, again starting press continues to exert pressure with 4 pairs of hollow casting blanks 3 of T-shape anvil by cushion block 5 and jumping-up, until hollow casting blank 3 reaches the height H 1 of setting, obtain the blank 10 after jumping-up,

3. as Fig. 2, shown in Fig. 3, the lower positioning table 8 that upper end is equipped with to backstay 9 is placed in the crowded centre bore with drain cap 6 of expansion, said apparatus is positioned on press platform, after being reheated, blank after jumping-up 10 is placed on lower positioning table 8, press is gently depressed, blank 10 after jumping-up is fully contacted with lower positioning table 8, realize the centering of the blank 10 after jumping-up, location, press lifts, expansion is squeezed to be set in to expand with cylinder mould 7 and squeeze on drain cap 6, the expansion that center is had to a locating hole is squeezed and to be placed on above the blank 10 after jumping-up with drift 11, and lower backstay 9 is inserted and expand crowded using in the locating hole of drift 11, hollow cushion block 12 is placed in to expand and squeezes with above drift 11, start press, by hollow cushion block 12 and expansion, squeeze and exert pressure with the blank 10 after 11 pairs of jumping-ups of drift, until expand, squeeze the height H 2 that reaches setting with the lower surface of drift 11, after more lower positioning table 8 being removed together with the backstay 9 on it, restarting press exerts pressure with the blank 10 after 11 pairs of jumping-ups of drift with expanding to squeeze by the hollow cushion block 12 installing additional, complete to expand and push through journey, obtain expanding the blank 13 after squeezing, wherein descend positioning table 8 and expand and squeeze by the shape of drift 11 according to technique initialization,

4. as shown in Figure 4, backward extrusion is placed on press platform with cylinder mould 7 together with the backward extrusion of laying on it with drain cap 14, after reheating, puts into blank 13 after expansion is squeezed backward extrusion with on cylinder mould 7 backward extrusion drain caps 14, backward extrusion is placed on above the blank 13 expanding after squeezing with drift 15, and cushion block 16 is placed on to backward extrusion with above drift 15, starting press exerts pressure with 15 pairs of blanks 13 that expand after squeezing of drift by cushion block 16 and backward extrusion, complete backward extrusion whole deformation process, obtain the forging 17 being shaped, wherein the number of cushion block 16 is according to technique initialization.

Claims

1. a forging method that adopts hollow casting blank thermoforming cylindrical, it is characterized in that the hollow casting blank of centrifugal casting first by machined, to remove the defect on endoporus top layer, after being heated again the jumping-up of setting with mould in Upsetting reach setting height, melt down again after heating, the expansion that is placed on setting is squeezed with expanding crowded distortion in mould, after again the blank after the crowded distortion of expansion being reheated, be placed on the backward extrusion of setting with carrying out backward extrusion distortion in mould, reach forging requirement size, concrete operation step is:

1. the endoporus of the hollow casting blank of centrifugal casting (3) is removed to the defect layer of 8-10mm by machined;

2. drain cap for jumping-up (1) is placed on press platform together with the Upsetting being assembled together with it thick cylinder mould (2), hollow casting blank (3) after heating is placed on to jumping-up interior for jumping-up on drain cap (1) with cylinder mould (2), again T-shape anvil (4) for jumping-up is placed on hollow casting blank (3), starting press is exerted pressure and makes it produce Upsetting to stop exerting pressure when the upper surface of T-shape anvil (4) jumping-up for flushes with mould (2) upper end with jumping-up hollow casting blank (3) by jumping-up T-shape anvil (4), on T-shape anvil (4) for jumping-up, place again cushion block (5), again start press by cushion block (5) and for jumping-up T-shape anvil (4) hollow casting blank (3) is continued to exert pressure, until hollow casting blank (3) reaches the height H 1 of setting, obtain the blank (10) after jumping-up,

3. the lower positioning table (8) that upper end is equipped with to backstay (9) is placed in and expands the centre bore squeezing with drain cap (6), said apparatus is positioned on press platform, after being reheated, blank after jumping-up (10) is placed on lower positioning table (8), press is gently depressed, blank (10) after jumping-up is fully contacted with lower positioning table (8), realize the centering of the blank (10) after jumping-up, location, press lifts, to expand to squeeze to be set in to expand with cylinder mould (7) and squeeze with on drain cap (6), the expansion that center is had to a locating hole is squeezed with drift (11) and is placed on blank (10) after jumping-up above, and lower backstay (9) is inserted and expand in the locating hole squeezing with drift (11), hollow cushion block (12) is placed in to expand and squeezes with drift (11) above, start press, by hollow cushion block (12) and expansion, squeeze and with drift (11), the blank after jumping-up (10) is exerted pressure, until expand, squeeze the height H 2 that reaches setting with the lower surface of drift (11), after more lower positioning table (8) being removed together with the backstay on it (9), restarting press exerts pressure to the blank after jumping-up (10) by the hollow cushion block (12) and the crowded drift (11) of expansion that install additional, complete to expand and push through journey, obtain expanding the blank (13) squeezing after distortion, wherein descend positioning table (8) and expand extruding and use the shape of drift (11) and the number of hollow cushion block (12) according to technique initialization,

4. drain cap for backward extrusion (14) is placed on press platform together with the backward extrusion cylinder mould (7) of laying on it, after reheating, puts on backward extrusion cylinder mould (7) backward extrusion drain cap (14) blank (13) after expansion is squeezed, drift for backward extrusion (15) is placed on to blank (13) after expand squeezing above, and by cushion block (16) be placed on drift for backward extrusion (15) above, start press by cushion block (16) and for backward extrusion drift (15) blank (13) expanding after squeezing is exerted pressure, complete backward extrusion whole deformation process, obtain the forging (17) being shaped, wherein the number of cushion block (16) is according to technique initialization.