CN216680044U - Large-scale step barrel forging die - Google Patents
Large-scale step barrel forging die Download PDFInfo
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- CN216680044U CN216680044U CN202123385856.XU CN202123385856U CN216680044U CN 216680044 U CN216680044 U CN 216680044U CN 202123385856 U CN202123385856 U CN 202123385856U CN 216680044 U CN216680044 U CN 216680044U
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Abstract
The utility model relates to a large-scale step barrel part forging die which is provided with a reverse extrusion punch and a lower die, wherein a main die cavity with an opening at the top is arranged in the lower die, a base plate connecting hole which is vertically communicated with the bottom of the main die cavity is arranged at the bottom of the main die cavity, a lower base plate which is matched with the base plate connecting hole in structure is arranged in the base plate connecting hole, an ejector rod which can move up and down is arranged at the center of the lower base plate, a flat punch is movably arranged at the bottom of the reverse extrusion punch, and a supporting plate which can horizontally rotate is arranged at the position, located on the outer side of the opening at the top of the main die cavity, at the top of the lower die. The large-scale step barrel part forging die effectively ensures the utilization rate of materials through a forward and backward extrusion technology, the internal structure of a forged piece product formed by die forging is continuous and compact, the mechanical performance of the product is effectively ensured, the service life of the product is prolonged, and the product quality is effectively guaranteed.
Description
Technical Field
The utility model relates to step barrel part machining, in particular to a large step barrel part forging die.
Background
The step cylinder part is applied to a plurality of devices, such as a hydraulic cylinder in a hydraulic transmission system, and an external cylinder barrel is the step cylinder part.
At present, the production and processing modes of the step cylinder part comprise casting processing, machining and ring rolling processing; for step cylinder parts with smaller structures, the processing modes are more convenient, the processing difficulty is small, and the processing efficiency is high, but for large-scale step cylinder parts, such as hydraulic cylinders applied to large-scale equipment such as large-scale mine hopper cars and the like, the structural volume of the hydraulic cylinders is very large for matching application, so that the hydraulic cylinders forming the hydraulic cylinders are very large in volume, the hydraulic cylinders belong to the step cylinder parts, for the processing of the large-scale step cylinder parts, the defects of air holes, sand holes, insufficient pouring, shrinkage cavities, shrinkage porosity, slag inclusion and the like are easily generated in the traditional casting processing, the product quality is influenced, the structure control difficulty of the cast product is large, and the performance is not stable enough; the machining mode is that a metal bar is clamped on a machine tool, and the bar is machined in a turning mode, so that the machining mode is low in material utilization rate for the step cylinder part, large-sized step cylinder part is inconvenient to clamp by the machine tool, and the internal structure of the machined step cylinder part is discontinuous due to cutting, so that the performance of a product is unstable; in addition, the ring rolling processing mode is only suitable for the production and processing of small-sized step cylinder parts, and large-sized step cylinder parts are long in product length, so that the ring rolling action cannot be carried out, and the limitation is large.
Disclosure of Invention
The utility model aims to solve the technical problem of providing a large-scale step barrel part forging die which is high in material utilization rate and capable of effectively guaranteeing the mechanical performance of a product.
In order to solve the technical problems, the utility model is realized by the following technical scheme: the utility model provides a large-scale step section of thick bamboo spare forges mould, has anti-extrusion drift and lower mould, be provided with open-top's master mode chamber in the lower mould, the bottom be provided with the backing plate joining hole of intercommunication about master mode chamber bottom, be provided with the lower bolster rather than the structure is identical in the backing plate joining hole, the center of lower bolster is provided with the ejector pin that can move about from top to bottom, the activity of anti-extrusion drift bottom is provided with flat drift, the lower mould top is located master mode chamber open-top's the outside and is provided with the layer board that can carry out horizontal rotation.
Furthermore, the flat punch is in a convex structure, a concave part is arranged at the part, close to the top, of the outer side of the flat punch, the bottom surface of the flat punch is matched with the top opening of the main die cavity, and the flat punch can be pressed into the top opening of the main die cavity through a reverse extrusion punch; the center of the top of the flat punch is provided with a trepanning matched with the bottom structure of the reverse extrusion punch, and the flat punch can be sleeved at the bottom of the reverse extrusion punch through the trepanning; the side part of the flat punch, which is positioned at the depressed part, is provided with a thread positioning hole which is communicated with the trepanning, a flat punch fastening bolt which is in thread fit with the thread positioning hole is screwed in the thread positioning hole, the tail end of the flat punch fastening bolt is abutted against the side surface of a reverse extrusion punch inserted in the trepanning, and the distance from the front end to the central line of the flat punch is not more than the radius of the bottom surface of the flat punch.
Furthermore, the number of the thread positioning holes is at least two, and the thread positioning holes are distributed in a circular array by taking the end face center of the flat punch as an axis.
Furthermore, the outer side of the part, matched with the trepanning, of the reverse extrusion punch is provided with an inward-concave positioning groove, and the positioning groove and the threaded positioning hole correspond to each other in the horizontal direction.
Furthermore, the positioning groove is an arc-shaped groove.
Furthermore, a punch positioning ring in sleeve joint fit with the opening at the top of the main die cavity is arranged at the opening at the top of the main die cavity; the punch positioning ring is of a T-shaped structure, a centering hole which is communicated up and down is formed in the center of the punch positioning ring, and a limiting flange which is integrally formed with the punch positioning ring is arranged at the position, close to the top, of the outer side of the punch positioning ring.
Furthermore, the supporting plate is movably connected with the lower die through a rotary bearing, and the rotary bearing is connected with the supporting plate and the lower die through a rotary shaft fixedly arranged at the top of the lower die.
Furthermore, the top of the lower die is provided with a threaded connection hole, and the rotating shaft is arranged in the threaded connection hole and is in threaded connection with the threaded connection hole.
Further, an inverted pulling die cavity is arranged between the main die cavity and the base plate joint hole, the vertical section of the inverted pulling die cavity is of a trapezoidal structure, and the inclination angle of the wall surface of the inverted pulling die cavity is 2 degrees.
Furthermore, the vertical sections of the base plate connecting hole and the lower base plate are both in a trapezoidal structure, the center of the end face of the lower base plate is provided with an ejection hole which is communicated up and down, the vertical section of the ejection hole is in a T-shaped structure, and the structure of the ejector rod is matched with that of the ejection hole and is sleeved in the ejection hole.
Compared with the prior art, the utility model has the advantages that: the large-scale step barrel part forging die effectively ensures the utilization rate of materials through a forward and backward extrusion technology, the internal structure of a forged piece product formed by die forging is continuous and compact, the mechanical performance of the product is effectively ensured, the service life of the product is prolonged, and the product quality is effectively guaranteed.
Drawings
The utility model is further described below with reference to the accompanying drawings.
FIG. 1 is a sectional view of a large stepped cylinder forging die structure according to the present invention;
FIG. 2 is a sectional view of a flat punch structure in the forging die for large stepped cylindrical parts according to the present invention;
FIG. 3 is an enlarged view of A in FIG. 1;
FIG. 4 is a sectional view of a positioning ring structure of a punch head in the forging die for large stepped cylindrical parts according to the present invention;
FIG. 5 is a schematic diagram of the forging process of the large stepped cylinder forging die of the present invention.
In the figure: 1. a backward extrusion punch; 1-1, positioning grooves; 2. fastening a bolt; 3. flattening the punch; 3-1, trepanning; 3-2, positioning a threaded hole; 3-3, a recess; 4. a rotating shaft; 5. a support plate; 6. a rotating bearing; 7. positioning a punch positioning ring; 7-1, centering holes; 7-2, limiting flanges; 8. a lower die; 8-1, a main mold cavity; 8-2, reversely drawing the die cavity; 8-3, connecting holes of the base plate; 8-4, axially connecting holes; 9. a lower base plate; 10. a top rod; 11. a metal bar stock; 12. and (5) forging.
Detailed Description
The utility model is described in detail below with reference to the following figures and embodiments:
the large-scale step barrel part forging die shown in the figure 1 is provided with a reverse extrusion punch 1 and a lower die 8, a main die cavity 8-1 with an open top is arranged in the lower die 8, a base plate connecting hole 8-3 which is vertically communicated with the bottom of the main die cavity 8-1 is formed in the bottom of the lower die, a lower base plate 9 matched with the base plate connecting hole 8-3 in structure is arranged in the base plate connecting hole 8-3, an ejector rod 10 capable of moving up and down is arranged at the center of the lower base plate 9, a flat punch 3 is movably arranged at the bottom of the reverse extrusion punch 1, and a supporting plate 5 capable of horizontally rotating is arranged on the outer side, located at the open top of the main die cavity 8-1, of the top of the lower die 8.
As shown in fig. 2, in order to upset the metal bar 11 placed in the main die cavity 8-1, the flat punch 3 is in a convex structure, a concave part 3-3 is arranged at the outer side close to the top, the bottom surface is matched with the top opening of the main die cavity 8-1, and the flat punch 3 can be pressed into the top opening of the main die cavity 8-1 through the reverse extrusion punch 1; the center of the top of the flat punch 3 is provided with a trepanning 3-1 which is matched with the bottom structure of the reverse extrusion punch 1, and the flat punch 3 can be sleeved at the bottom of the reverse extrusion punch 1 through the trepanning 3-1; the side part of the flat punch 3 positioned at the concave part 3-3 is provided with a threaded positioning hole 3-2 communicated with the trepanning 3-1, a flat punch fastening bolt 2 in threaded fit with the threaded positioning hole 3-2 is screwed in the threaded positioning hole 3-2, the tail end of the flat punch fastening bolt 2 is abutted against the side surface of a reverse extrusion punch 1 inserted in the trepanning 3-1, and the distance from the front end to the central line of the flat punch 3 is not more than the bottom surface radius of the flat punch 3, so that the flat punch fastening bolt 2 arranged on the flat punch cannot interfere the flat punch 3 to enter the opening of the main die cavity 8-1.
In order to ensure that the flat punch 3 and the reverse extrusion punch 1 can be fixedly connected together after being assembled and ensure the balance of the flat punch 3 on the reverse extrusion punch 1, at least two threaded positioning holes 3-2 are arranged and distributed in a circular array by taking the end face center of the flat punch 3 as an axis.
As shown in fig. 3, in order to effectively fix the flat punch 3 sleeved on the backward extrusion punch 1 and prevent the flat punch from slipping during operation, an inward concave positioning groove 1-1 is arranged on the outer side of a part of the backward extrusion punch 1, which is matched with the trepanning 3-1, and the positioning groove 1-1 and the threaded positioning hole 3-2 correspond to each other in the horizontal direction.
In order to facilitate the matching of the flat punch fastening bolt 2 and the positioning groove 1-1, the positioning groove 1-1 is an arc-shaped groove.
In order to center the backward extrusion punch 1, a punch positioning ring 7 matched with the top opening of the main die cavity 8-1 in a sleeved mode is arranged at the top opening of the main die cavity; the punch positioning ring 7 is of a T-shaped structure, a centering hole 7-1 which is communicated up and down is formed in the center of the punch positioning ring 7, the centering hole 7-1 is in clearance fit with the backward extrusion punch 1, and a limiting flange 7-2 which is integrally formed with the punch positioning ring 7 is arranged at the position, close to the top, of the outer side of the punch positioning ring 7, so that the position of the opening of the punch positioning ring 7 at the top of the main die cavity 8-1 can be limited.
In order to facilitate the horizontal rotation of the supporting plate 5 relative to the lower die 8, the supporting plate 5 is movably connected with the lower die 8 through a rotary bearing 6, and the rotary bearing 6 is connected with the supporting plate 5 and the lower die 8 through a rotary shaft 4 fixedly arranged at the top of the lower die 8.
In order to facilitate the installation of the supporting plate 5 and the rotary bearing 6 on the lower die 8 and prevent the falling, a threaded connection hole is formed in the top of the lower die 8, and the rotary shaft 4 is arranged in the threaded connection hole and is in threaded connection with the threaded connection hole.
In order to prevent the backward extrusion punch 1 from being brought out of a die-forged workpiece 12 in the main die cavity 8-1 during upward return stroke, an inverted drawing die cavity 8-2 is arranged between the main die cavity 8-1 and the cushion plate connecting hole 8-3, the vertical section of the inverted drawing die cavity 8-2 is in a trapezoidal structure, and the inclination angle of the wall surface of the inverted drawing die cavity is 2 degrees.
In order to limit the position of the lower cushion plate 9 and facilitate the assembly and disassembly between the lower cushion plate 9 and the lower die 8, the vertical sections of the cushion plate joining hole 8-3 and the lower cushion plate 9 are both in a trapezoidal structure, the center of the end surface of the lower cushion plate 9 is provided with an ejection hole which is communicated up and down, the vertical section of the ejection hole is in a T-shaped structure, and the structure of the ejector rod 10 is matched with the structure of the ejection hole and is sleeved in the ejection hole.
The specific processing method comprises the following steps: fixedly mounting a reverse extrusion punch 1 and a lower die 8 on a forging press machine as shown in fig. 5, wherein the bottom of the reverse extrusion punch 1 corresponds to the top of a main die cavity 8-1 on the lower die 8 up and down; at the moment, the supporting plate 5 is suspended outside the top of the lower die 8 through the rotating bearing 6, the flat punch 3 is placed in the center of the top of the supporting plate 5, and a sleeve hole 3-1 in the flat punch 3 faces upwards; placing a punch positioning ring 7 at the opening at the top of a main die cavity 8-1, starting a forging machine tool, controlling the backward extrusion punch 1 to descend, ensuring that the tail end of the backward extrusion punch 1 can penetrate through a positioning central hole 7-1 in the punch positioning ring 7, and realizing the centering work of the backward extrusion punch 1; after the centering of the backward extrusion punch 1 is finished, the backward extrusion punch 1 is reset upwards, the punch positioning ring 7 is taken down from the lower die 8, then the supporting plate 5 is pushed to rotate by taking the rotary bearing 6 as an axis until the supporting plate 5 rotates to the position right above the lower die 8, and at the moment, the flat punch 3 on the supporting plate 5 is required to be vertically corresponding to the bottom of the backward extrusion punch 1; then controlling the backward extrusion punch 1 to descend to enable the tail end of the bottom of the backward extrusion punch 1 to be sleeved in a trepanning hole 3-1 of the flat punch 3, screwing down and fixing the flat punch 3 and the backward extrusion punch 1 through a flat punch fastening bolt 2 on the flat punch 3, then controlling the backward extrusion punch 1 to reset upwards, driving the flat punch 3 to synchronously move upwards by the backward extrusion punch 1, and then pushing the supporting plate 5 away from the position right above the lower die 8 to enable an opening at the top of the main die cavity 8-1 to be exposed outside and not shielded and interfered by the supporting plate 5; then controlling the workbench bearing the lower die 8 to move outwards, vertically placing a heated metal bar 11 in a main die cavity 8-1 of the lower die 8, then controlling the workbench bearing the lower die 8 to reset, starting a forging machine tool, driving a flat punch 3 to forge and press the metal bar 11 in the main die cavity 8-1 by a reverse extrusion punch 1, upsetting the metal bar 11, controlling the reverse extrusion punch 1 to reset upwards after the external shape of the metal bar 11 is preliminarily matched with the structure of the main die cavity 8-1, then pushing a supporting plate 5 to rotate right above the lower die 8, then controlling the reverse extrusion punch 1 to descend, enabling the bottom of the flat punch 3 to be in contact with the top of the supporting plate 5, then loosening a flat punch fastening bolt 2 for tightly jacking the reverse extrusion punch 1, controlling the reverse extrusion punch 1 to be separated from a trepanning on the flat punch 3, and pushing the supporting plate 5 after the reverse extrusion punch 1 is separated from the flat punch 3, so that the flat punch 3 is driven to rotate away from the opening at the top of the main die cavity 8-1; then controlling a backward extrusion punch 1 to punch the upset blank until the upset blank is backward extruded into a required forged piece 12; and after the machining is finished, the backward extrusion punch 1 is controlled to return upwards and reset, then the workbench bearing the lower die 8 is controlled to move outwards, and finally the forge piece 12 in the main die cavity 8-1 is ejected upwards through the ejector rod 10.
The large-scale step barrel part forging die effectively ensures the utilization rate of materials through a forward and backward extrusion technology, the internal structure of a forged piece product formed by die forging is continuous and compact, the mechanical performance of the product is effectively ensured, the service life of the product is prolonged, and the product quality is effectively guaranteed.
It is to be emphasized that: the above embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and all simple modifications, equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention are within the scope of the technical solution of the present invention.
Claims (10)
1. The utility model provides a large-scale step section of thick bamboo spare forges mould, has anti-extrusion drift (1) and lower mould (8), be provided with open-top's main die cavity (8-1) in lower mould (8), the bottom be provided with backing plate interlock hole (8-3) of main die cavity (8-1) bottom intercommunication from top to bottom, be provided with in backing plate interlock hole (8-3) with the identical lower bolster (9) of its structure, the center of lower bolster (9) is provided with ejector pin (10) that can move about from top to bottom, its characterized in that: the bottom of the reverse extrusion punch (1) is movably provided with a flat punch (3), and the top of the lower die (8) is provided with a supporting plate (5) which can horizontally rotate and is positioned on the outer side of the top opening of the main die cavity (8-1).
2. The large-scale step barrel forging die according to claim 1, wherein: the flat punch (3) is of a convex structure, a concave part (3-3) is arranged at the position, close to the top, of the outer side of the flat punch, the bottom surface of the flat punch is matched with the top opening of the main die cavity (8-1), and the flat punch (3) can be pressed into the top opening of the main die cavity (8-1) through the reverse extrusion punch (1); the center of the top of the flat punch (3) is provided with a trepanning (3-1) matched with the bottom structure of the reverse extrusion punch (1), and the flat punch (3) can be sleeved at the bottom of the reverse extrusion punch (1) through the trepanning (3-1); the side part of the flat punch (3) positioned at the concave part (3-3) is provided with a thread positioning hole (3-2) communicated with the trepanning (3-1), the thread positioning hole (3-2) is internally screwed with a flat punch fastening bolt (2) in thread fit with the thread positioning hole, the tail end of the flat punch fastening bolt (2) is abutted against the side surface of a reverse extrusion punch (1) inserted in the trepanning (3-1), and the distance from the front end to the central line of the flat punch (3) is not more than the radius of the bottom surface of the flat punch (3).
3. The large-scale step barrel forging die of claim 2, wherein: the number of the thread positioning holes (3-2) is at least two, and the thread positioning holes are distributed in a circular array by taking the end face center of the flat punch (3) as an axis.
4. The large-scale step barrel forging die of claim 2, wherein: an inward-concave positioning groove (1-1) is formed in the outer side of the part, matched with the trepanning (3-1), of the reverse extrusion punch (1), and the positioning groove (1-1) corresponds to the threaded positioning hole (3-2) in the horizontal direction.
5. The large-scale step barrel forging die of claim 4, wherein: the positioning groove (1-1) is an arc-shaped groove.
6. The large-scale step barrel forging die according to claim 1, wherein: a punch positioning ring (7) in sleeve fit with the top opening of the main die cavity (8-1) is arranged at the top opening of the main die cavity; the punch positioning ring (7) is of a T-shaped structure, the center of the punch positioning ring is provided with a positioning middle hole (7-1) which is communicated up and down, and the position of the outer side, which is close to the top, is provided with a limiting flange (7-2) which is integrally formed with the punch positioning ring.
7. The large-scale step barrel forging die according to claim 1, wherein: the supporting plate (5) is movably connected with the lower die (8) through a rotary bearing (6), and the rotary bearing (6) is connected with the supporting plate (5) and the lower die (8) through a rotary shaft (4) fixedly arranged at the top of the lower die (8).
8. The large-scale step barrel forging die of claim 7, wherein: the top of the lower die (8) is provided with a threaded connecting hole, and the rotating shaft (4) is arranged in the threaded connecting hole and is in threaded connection with the threaded connecting hole.
9. The large-scale step barrel forging die according to claim 1, wherein: an inverted pulling mold cavity (8-2) is arranged between the main mold cavity (8-1) and the base plate joint hole (8-3), the vertical section of the inverted pulling mold cavity (8-2) is of a trapezoidal structure, and the inclination angle of the wall surface of the inverted pulling mold cavity is 2 degrees.
10. The large-scale step barrel forging die according to claim 1, wherein: the vertical sections of the base plate connecting holes (8-3) and the lower base plate (9) are both in a trapezoidal structure, the center of the end face of the lower base plate (9) is provided with an ejection hole which is communicated up and down, the vertical section of the ejection hole is in a T-shaped structure, and the structure of the ejector rod (10) is matched with that of the ejection hole and is sleeved in the ejection hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123385856.XU CN216680044U (en) | 2021-12-30 | 2021-12-30 | Large-scale step barrel forging die |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123385856.XU CN216680044U (en) | 2021-12-30 | 2021-12-30 | Large-scale step barrel forging die |
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| Publication Number | Publication Date |
|---|---|
| CN216680044U true CN216680044U (en) | 2022-06-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202123385856.XU Active CN216680044U (en) | 2021-12-30 | 2021-12-30 | Large-scale step barrel forging die |
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| CN (1) | CN216680044U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115301880A (en) * | 2022-09-05 | 2022-11-08 | 中国第一重型机械股份公司 | Large blind hole forge piece forging die and forging method |
-
2021
- 2021-12-30 CN CN202123385856.XU patent/CN216680044U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115301880A (en) * | 2022-09-05 | 2022-11-08 | 中国第一重型机械股份公司 | Large blind hole forge piece forging die and forging method |
| CN115301880B (en) * | 2022-09-05 | 2024-01-12 | 中国第一重型机械股份公司 | Forging die and forging method for large blind hole forging |
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