CN114147158A - Vertical forging process for high-quality shaft forgings - Google Patents
Vertical forging process for high-quality shaft forgings Download PDFInfo
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- CN114147158A CN114147158A CN202111561189.8A CN202111561189A CN114147158A CN 114147158 A CN114147158 A CN 114147158A CN 202111561189 A CN202111561189 A CN 202111561189A CN 114147158 A CN114147158 A CN 114147158A
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- 238000005242 forging Methods 0.000 title claims abstract description 83
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000007599 discharging Methods 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000002994 raw material Substances 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 9
- 239000000463 material Substances 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 7
- 238000003825 pressing Methods 0.000 description 6
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000007639 printing Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/002—Hybrid process, e.g. forging following casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
- B21K1/00—Making machine elements
- B21K1/06—Making machine elements axles or shafts
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Forging (AREA)
Abstract
The invention relates to a vertical forging process of a high-quality shaft forging, which comprises the following steps of blanking; upsetting and drawing out; marking small steps at two ends; pre-drawing small steps at two ends, and reserving the deformation of the last fire time; erecting a prefabricated blank forging, placing small steps at two ends into a die, placing the small step at the upper part into an upper die, and placing the small step at the lower part into a lower die; upsetting the forged piece of the prefabricated blank vertically to thicken the middle section and enable the diameter to reach the forming size of the forged piece; demolding; and drawing the small steps at the two ends in place according to the forming size of the forge piece. The invention saves raw materials, has more uniform structure, can correct the coaxiality, has small deformation amount each time, can avoid the generation of cracks and improve the product quality.
Description
Technical Field
The invention relates to the technical field of forging of shaft forgings, in particular to a vertical forging process of a high-quality shaft forging.
Background
In the free forging industry, large shaft forgings are usually forged, particularly step shafts with thick middle diameters and thin two end diameters are used in the gear industry, and referring to fig. 1, the step shafts are generally used for transmission gear shafts, idler shafts on mechanical equipment and the like. The middle section of the shaft forging has thicker diameter, the two ends have thinner diameter and larger diameter difference, and according to the forging method of the conventional shaft forging, after the forging ratio is made, the blank is ejected to form a cylinder, then the two ends are printed and divided, and the step with the smaller diameter at the two ends is pulled out, which is shown in figure 2; however, the conventional process molding method has the limitation of number printing length: the minimum length L1 of the blank at the marking end cannot be smaller than 1/3 of the ejection diameter D, if the forging plasticity of the material of the product is poor, the ejection length L1 during marking is not smaller than 1/2 of the ejection diameter D, if the condition cannot be met, when a small step is drawn out after marking, a central shrinkage cavity is formed in the center of two ends of the small step during the drawing process, so that the product is rejected due to unqualified size, and the reference is shown in FIG. 3; and the material of the main shaft is 17-4PH, which belongs to precipitation hardening martensite aged stainless steel, the plasticity is poor, and the surface of the forged piece is easy to crack in the forging process.
Disclosure of Invention
The invention aims to overcome the defects and provide a vertical forging process for high-quality shaft forgings, so that raw materials are saved and the product quality is improved.
The purpose of the invention is realized as follows:
the utility model provides a vertical forging process of high quality axle class forging for produce the step axle, the step axle includes the little step at interlude and both ends, and it includes following content:
step one, blank ejection: the diameter of the blank is smaller than the diameter of the middle section of the forged piece during blank discharging and is larger than half of the diameter of the middle section of the forged piece;
step two, upsetting and drawing out;
step three, marking small steps at two ends;
step four, pre-drawing small steps at two ends, and keeping the deformation of the last fire;
step five, erecting the prefabricated blank forged piece, placing the small steps at two ends into the die, placing the small step at the upper part into the upper die, and placing the small step at the lower part into the lower die;
step six: upsetting the forged piece of the prefabricated blank vertically to thicken the middle section and enable the diameter to reach the forming size of the forged piece;
step seven: demolding;
step eight: and drawing the small steps at the two ends in place according to the forming size of the forge piece.
Further, the reserved forging ratio in the fourth step is more than 1.5.
Furthermore, in the fifth step, the upper die and the lower die have the same structure and are both circular ring-shaped dies.
Further, in the seventh step, rounding is performed after demolding.
Compared with the prior art, the invention has the beneficial effects that:
(1) the invention does not need to perform blank discharging according to the diameter of the middle section of the product size during blank discharging, the blank discharging diameter is reduced, the limitation of number printing material distribution is avoided, and no material is needed to be added when the small steps at the two ends are drawn out, so the invention can save raw materials, and the same product can save 30% of the material weight by using the forging process technology of the invention.
(2) When the last hot forging is carried out, the middle section is upset, the small steps at the two ends are drawn out, all parts of the product have deformation, the structure is more uniform, the small steps at the two ends are drawn out at last in the conventional process, the middle section has deformation, coarse crystals are easy to generate, and the structure difference of all parts is large.
(3) According to the invention, the upper small step and the lower small step are arranged in the tooling die when the middle section is upset, so that the coaxiality of the small steps at the two ends and the middle section with the large diameter can be easily controlled, the coaxiality of the steps at each section can be corrected, and the coaxiality can not be corrected by a conventional process.
(4) Because the product is made of stainless steel, the plasticity of the material is poor, and the product is easy to crack, when small steps at two ends are printed and pulled in a conventional process, cracks are easily generated at the roots of the steps due to large step fall; the invention has small deformation quantity each time, can avoid the generation of cracks and improve the product quality.
Drawings
Fig. 1 is a schematic structural view of a step shaft.
Fig. 2 is a schematic diagram of a deformation process of comparative example 1.
FIG. 3 is a schematic view of an inferior product in comparative example 1.
FIG. 4 is a schematic process diagram of example 1 of the present invention.
Fig. 5 is a schematic diagram of a modification process of embodiment 2 of the present invention.
Fig. 6 is a schematic diagram of a modification process of embodiment 3 of the present invention.
FIG. 7 is a schematic drawing of a forging of embodiment 4 of the invention.
Wherein:
the device comprises a step shaft 1, a middle section 11, a small step 12, an upper die 2 and a lower die 3.
Detailed Description
For a better understanding of the technical aspects of the present invention, reference will now be made in detail to the accompanying drawings. It should be understood that the following specific examples are not intended to limit the embodiments of the present invention, but are merely exemplary embodiments of the present invention. It should be noted that the description of the positional relationship of the components, such as the component a is located above the component B, is based on the description of the relative positions of the components in the drawings, and is not intended to limit the actual positional relationship of the components.
Example 1:
referring to fig. 4, fig. 4 is a schematic diagram of a process of a vertical forging process of a high-quality shaft forging. As shown in the figure, the vertical forging process of high-quality axle class forging of this embodiment 1, the production product is step axle 1, and step axle 1 includes little step 12 at interlude 11 and both ends, and the length of interlude 11 is 570mm, diameter are 845mm, and the length of little step 12 is 800mm, diameter are 350mm, and its process flow includes following content:
step one, blank ejection: the diameter of the blank is phi 580mm during blank discharging, so that the minimum length during blank discharging can be reduced, and no additional auxiliary material is required to be added;
step two, marking small steps 12 at two ends;
step three, pre-drawing the small steps 12 at the two ends, keeping the deformation of the last fire, and keeping the forging ratio to be more than 1.5;
step four, erecting the precast blank forge piece, placing the small steps 12 at two ends into the die, placing the small step 12 at the upper part into the upper die 2, and placing the small step 12 at the lower part into the lower die 3; the upper die 2 and the lower die 3 have the same structure and are both circular ring dies, and the diameter of a central hole of each circular ring is slightly larger than the diameter of the small step 12 of the forged piece of the prefabricated blank;
step five: vertically upsetting the precast blank forging by using a press to thicken the middle section 11, wherein the diameter of the forged blank reaches the design size of the forging;
step six, demolding;
and seventhly, drawing out the small steps 12 at the two ends to be formed in place according to the design size of the forge piece after demolding.
The blanking weight of the forging of this example 1 was 4.5T.
Example 2:
referring to fig. 5, fig. 5 is a schematic process diagram of a vertical forging process of a high-quality shaft forging. As shown in the figure, the main shaft is produced in the embodiment 2, and the product forming dimensions are as follows: the length of the middle section is 510mm, the diameter is 805mm, the length of the small step is 567.5mm, the diameter is 290mm, and the process flow comprises the following contents:
first heat number
Sawing off a steel ingot water gap at the initial forging temperature of 1170 ℃, lightly pressing the peripheral surface of the ingot body for about 20-30mm above the final forging temperature of 900 ℃, reversing the eight directions, performing small deformation and upsetting, and then returning to the furnace;
second fire number
Heating the forge piece to the initial forging temperature of 1180 ℃, returning the forge piece to the furnace, heating, discharging, transferring to an upsetting drain pan for upsetting, upsetting to be 800mm high above the final forging temperature of 900 ℃, and drawing out to be 670mm eight directions;
number of third fire
Then the forge piece is heated to the initial forging temperature of 1180 ℃ and taken out of the furnace and transferred to an upsetting drain pan for upsetting, and the forge piece is upset to 800mm above the final forging temperature of 900 ℃ and is drawn out to 620mm eight directions;
marking, and pulling small steps at two ends;
number of fourth fire
Then the forge piece is heated to the initial forging temperature of 1180 ℃ in a furnace, the forge piece is erected, the small steps at the two ends are respectively placed in the upper die and the lower die, and the middle section is thickened by a pressing machine at the final forging temperature of above 900 ℃ so that the diameter reaches the design size of the forge piece;
rounding after demoulding;
and finally, drawing out small steps at two ends to reach the design forming size of the forge piece.
Example 3:
referring to fig. 6, fig. 6 is a schematic process diagram of a vertical forging process of a high-quality shaft forging. As shown in the figure, the spindle is produced in the embodiment 3, and the product forming dimensions are as follows: the length of the middle section is 480mm, the diameter is 670mm, the length of the small step is 407.5mm, the diameter is 265mm, and the process flow comprises the following contents:
first heat number
Carrying out hot feeding on the electroslag steel ingot, lightly pressing the peripheral surface of the forging ingot body by about 20-30mm at the initial forging temperature of 1170 ℃, upsetting the local part of a small-end pit at the final forging temperature of 900 ℃, and returning the forging after small-deformation upsetting;
second fire number
Then the forge piece is heated to the initial forging temperature of 1180 ℃ and discharged out of the furnace, and is transferred to an upsetting drain pan for upsetting, and the forge piece is upset to 850mm height above the final forging temperature of 900 ℃ and is drawn out to 630mm eight directions;
number of third fire
Then the forge piece is heated to the initial forging temperature of 1180 ℃ and discharged out of the furnace, and is transferred to an upsetting drain pan for upsetting, and the forge piece is upset to 800mm above the final forging temperature of 900 ℃ and is drawn out to phi 620 mm;
number of fourth fire
Then, the forge piece is heated to the initial forging temperature of 1180 ℃ in a furnace, and is printed after being discharged, the pressing depth is about 40-50mm during the printing, and small steps at two ends are drawn at the final forging temperature of 900 ℃ or above;
number of fire
Then the forge piece is heated to the initial forging temperature of 1180 ℃ in a furnace, the forge piece is erected, the small steps at the two ends are respectively placed in the upper die and the lower die, and the middle section is thickened by a pressing machine at the final forging temperature of above 900 ℃ so that the diameter reaches the design size of the forge piece;
rounding after demoulding;
and finally, drawing out small steps at two ends to reach the design forming size of the forge piece.
Example 4:
referring to fig. 7, fig. 7 is a schematic process diagram of a vertical forging process of a high-quality shaft forging. As shown in the figure, the gear shaft is produced in the embodiment 4, and the product forming dimensions are as follows: the length of the middle section is 510mm, the diameter is 1044mm, the length of the small step at one end is 1100mm, the diameter is 351mm, the length of the small step at the other end is 673mm, the diameter is 444mm, and the process flow comprises the following contents:
first heat number
Pressing a steel ingot forging into a handle, chamfering and cutting a dead head at the initial forging temperature of 1200 ℃, and then upsetting to reach the height of 900mm and drawing out to 800mm at the final forging temperature of 850 ℃;
second fire number
The forge piece is returned to the furnace and heated to the initial forging temperature of 1200 ℃, taken out of the furnace and transferred to an upsetting drain pan for upsetting, and then is upset to 900mm high above the final forging temperature of 850 ℃, the diameter is phi 800mm by drawing a circle, the diameter is phi 500mm by drawing two blank ends, and the length is 850 mm;
number of third fire
The forging is heated to the initial forging temperature of 1200 ℃ and taken out of the furnace, the forging is erected, small steps at two ends are respectively placed in an upper die and a lower die, and then the forging is vertically upset by a press at the final forging temperature of 850 ℃ to enable the middle section to be thickened, and the diameter of the middle section reaches the design size of the forging;
rounding after demoulding;
and finally, drawing out small steps at two ends to reach the design forming size of the forge piece.
Comparative example 1:
referring to fig. 2 and 3, fig. 2 depicts a schematic diagram of a deformation process of comparative example 1. As shown, the process of comparative example 1 includes the following:
step one, forging ratio: calculating the small steps at two ends of the drawn length, wherein the length of the mark is less than 200mm and is far less than 1/2 of the diameter, so that the knockout length needs to be prolonged to 1/2 of the blank diameter according to the conventional forging method, and auxiliary materials need to be additionally added for forging the small steps at two ends;
step two, knockout: performing ejection according to the size of the product in the embodiment 1, wherein the diameter of the blank is phi 845 mm;
step three, marking and distributing materials at two ends;
step four, pulling out steps with small diameters at two ends;
the method of the comparative example 1 is used for producing the forged piece, the blanking weight of the forged piece needs 6.5T, and the blanking weight of the forged piece needed by the example 1 is 2T less than that of the comparative example 1.
The above is only a specific application example of the present invention, and the protection scope of the present invention is not limited in any way. All the technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.
Claims (4)
1. The vertical forging process of the high-quality shaft forge piece is characterized by comprising the following steps of: the production method is used for producing the step shaft, the step shaft comprises a middle section and small steps at two ends, and the production method comprises the following steps:
step one, blank ejection: the diameter of the blank is smaller than the diameter of the middle section of the forged piece during blank discharging and is larger than half of the diameter of the middle section of the forged piece;
step two, upsetting and drawing out;
step three, marking small steps at two ends;
step four, pre-drawing small steps at two ends, and keeping the deformation of the last fire;
step five, erecting the prefabricated blank forged piece, placing the small steps at two ends into the die, placing the small step at the upper part into the upper die, and placing the small step at the lower part into the lower die;
step six: upsetting the forged piece of the prefabricated blank vertically to thicken the middle section and enable the diameter to reach the forming size of the forged piece;
step seven: demolding;
step eight: and drawing the small steps at the two ends in place according to the forming size of the forge piece.
2. The vertical forging process of the high-quality shaft forgings, according to claim 1, is characterized in that: and in the fourth step, the reserved forging ratio is more than 1.5.
3. The vertical forging process of the high-quality shaft forgings, according to claim 1, is characterized in that: and in the fifth step, the upper die and the lower die have the same structure and are both circular ring-shaped dies.
4. The vertical forging process of the high-quality shaft forgings, according to claim 1, is characterized in that: and in the seventh step, rounding is carried out after demoulding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111561189.8A CN114147158A (en) | 2021-12-20 | 2021-12-20 | Vertical forging process for high-quality shaft forgings |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111561189.8A CN114147158A (en) | 2021-12-20 | 2021-12-20 | Vertical forging process for high-quality shaft forgings |
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| CN114147158A true CN114147158A (en) | 2022-03-08 |
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| CN202111561189.8A Pending CN114147158A (en) | 2021-12-20 | 2021-12-20 | Vertical forging process for high-quality shaft forgings |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114508017A (en) * | 2022-04-02 | 2022-05-17 | 陆利萍 | Concrete with high water permeability and processing method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1489910A1 (en) * | 1986-12-29 | 1989-06-30 | Краматорский Завод "Энергомашспецсталь" | Method of forging stepped-diameter forgings |
| CN201361670Y (en) * | 2009-03-16 | 2009-12-16 | 江阴南工锻造有限公司 | Device for forging heavy forging with two short and small ends and thick and big middle part |
| CN101979179A (en) * | 2010-09-16 | 2011-02-23 | 江苏金源锻造股份有限公司 | Method for forging thin and short shaft section at end of large-scale step shaft |
| CN104439028A (en) * | 2014-11-06 | 2015-03-25 | 通裕重工股份有限公司 | Forging process for forge pieces like stepped shafts |
| CN104942541A (en) * | 2015-06-12 | 2015-09-30 | 中钢集团邢台机械轧辊有限公司 | Method for forging battery pole piece roll blank |
| CN107008837A (en) * | 2017-05-10 | 2017-08-04 | 鞍钢重型机械有限责任公司 | A kind of inexpensive open die forging method of large-scale edger roll forging |
| CN110405121A (en) * | 2019-06-26 | 2019-11-05 | 中信重工机械股份有限公司 | A kind of forging method of Heavy Back-Up Roll forging |
| CN112872284A (en) * | 2020-12-25 | 2021-06-01 | 天津重型装备工程研究有限公司 | Multi-step shaft forging and forging method thereof |
-
2021
- 2021-12-20 CN CN202111561189.8A patent/CN114147158A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1489910A1 (en) * | 1986-12-29 | 1989-06-30 | Краматорский Завод "Энергомашспецсталь" | Method of forging stepped-diameter forgings |
| CN201361670Y (en) * | 2009-03-16 | 2009-12-16 | 江阴南工锻造有限公司 | Device for forging heavy forging with two short and small ends and thick and big middle part |
| CN101979179A (en) * | 2010-09-16 | 2011-02-23 | 江苏金源锻造股份有限公司 | Method for forging thin and short shaft section at end of large-scale step shaft |
| CN104439028A (en) * | 2014-11-06 | 2015-03-25 | 通裕重工股份有限公司 | Forging process for forge pieces like stepped shafts |
| CN104942541A (en) * | 2015-06-12 | 2015-09-30 | 中钢集团邢台机械轧辊有限公司 | Method for forging battery pole piece roll blank |
| CN107008837A (en) * | 2017-05-10 | 2017-08-04 | 鞍钢重型机械有限责任公司 | A kind of inexpensive open die forging method of large-scale edger roll forging |
| CN110405121A (en) * | 2019-06-26 | 2019-11-05 | 中信重工机械股份有限公司 | A kind of forging method of Heavy Back-Up Roll forging |
| CN112872284A (en) * | 2020-12-25 | 2021-06-01 | 天津重型装备工程研究有限公司 | Multi-step shaft forging and forging method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114508017A (en) * | 2022-04-02 | 2022-05-17 | 陆利萍 | Concrete with high water permeability and processing method thereof |
| CN114508017B (en) * | 2022-04-02 | 2023-09-19 | 微山汇丰新型建材有限责任公司 | Concrete with high water permeability and processing method thereof |
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