CN110814264B

CN110814264B - Flange forging process

Info

Publication number: CN110814264B
Application number: CN201911331933.8A
Authority: CN
Inventors: 耿代溪; 张玉敬; 王海昶
Original assignee: Jinan Taikang Forging Co Ltd
Current assignee: Jinan Taikang Forging Co Ltd
Priority date: 2019-12-21
Filing date: 2019-12-21
Publication date: 2021-04-13
Anticipated expiration: 2039-12-21
Also published as: CN110814264A

Abstract

The invention discloses a flange forging process, which belongs to the technical field of flange production and comprises the following steps: step S1: cutting, namely cutting the strip-shaped blank with the square cross section into a plurality of square blanks; step S2: heating, namely placing the square billet in a heating furnace for heating, so that the temperature of the square billet is higher than the recrystallization temperature and lower than the temperature of a solidus line; step S3: rounding, namely placing a square blank in a rounding die, and forging the square blank into a cylindrical blank; step S4: at the free end, upsetting the heated blank by using a press machine, and then punching the blank by using a punch; s5: ring rolling, namely mounting the blank on a ring rolling machine for ring rolling, and enlarging the central hole of the blank; step S6: annealing, namely placing the blank in a resistance furnace for annealing; and step S7, turning, namely turning the flange by using a lathe. The invention has the effect of improving the forging efficiency.

Description

Flange forging process

Technical Field

The invention relates to the technical field of flange production, in particular to a flange forging process.

Background

Forging is a processing method which utilizes forging machinery to apply pressure on a metal blank to cause the metal blank to generate plastic deformation so as to obtain a forged piece with certain mechanical property, certain shape and certain size. The defects of as-cast porosity and the like generated in the smelting process of metal can be eliminated through forging, the microstructure is optimized, and meanwhile, because the complete metal streamline is preserved, the mechanical property of the forging is generally superior to that of a casting made of the same material. Forging is one of the most common ways in flange production.

At present, the common flange manufacturing process includes the following steps S1: cutting, namely cutting the blank from the square blank; step S2: heating, namely placing the blank in a heating furnace for heating, so that the temperature of the blank is higher than the recrystallization temperature and lower than the temperature of a solidus line; step S3: free forging, namely forging the heated blank into round steel by using a press, upsetting, and punching the blank by using a punch; s4: the blank is arranged on a ring rolling machine to be rolled, and axial pressure is applied to the edge, close to the outer circle, of the side wall of the end face of the blank while the ring is rolled, so that the side wall of the end face of the blank forms a flange neck; step S5: annealing, namely placing the blank in a resistance furnace for annealing; and S6, turning, namely turning the flange by using a lathe, wherein when the square billet is forged into round steel, the edge angle of the square steel of a press machine needs to be used for forging and pressing for many times, so that the square billet is forged into the round steel, the square billet needs to be frequently rotated in the process of forging the square billet into the round steel, the square billet needs to be hammered for many times by using the press machine after each rotation, the edge angle of the square billet is hammered to form a cambered surface, and the round steel is prepared.

The above prior art solutions have the following drawbacks: this requires a lot of time because the square billet needs to be rotated frequently.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a flange forging process which has the effect of improving the forging production efficiency.

The above object of the present invention is achieved by the following technical solutions: a flange forging process is characterized in that: the method comprises the following steps: step S1: cutting, namely cutting the strip-shaped blank with the square cross section into a plurality of square blanks; step S2: heating, namely placing the square billet in a heating furnace for heating, so that the temperature of the square billet is higher than the recrystallization temperature and lower than the temperature of a solidus line; step S3: rounding, namely placing a square blank in a rounding die, and forging the square blank into a cylindrical blank; step S4: at the free end, upsetting the heated blank by using a press machine, and then punching the blank by using a punch; s5: ring rolling, namely mounting the blank on a ring rolling machine for ring rolling, and enlarging the central hole of the blank; step S6: annealing, namely placing the blank in a resistance furnace for annealing; and step S7, turning, namely turning the flange by using a lathe.

Through adopting above-mentioned technical scheme, utilize system circle mould to realize the system circle of square billet, place the square billet on system circle mould, then utilize the press to exert pressure to the square billet, make its shaping be the round steel to need not to rotate the square billet many times, just realized the forging of round steel, simplified the operation, saved the time, thereby improved forged efficiency.

The present invention in a preferred example may be further configured to: in step S1, the weight of the square billet before cutting is 1.05 to 1.10 times the weight of the qualified flange in step S6.

By adopting the technical scheme, because the material of the blank can be lost in the subsequent processes of deburring and rough turning, the machining allowance needs to be left before the blank is cut.

The present invention in a preferred example may be further configured to: in step S4, the blank is heated by a natural gas heating furnace, wherein the temperature of the natural gas heating furnace is 1180-1220 ℃.

Through adopting above-mentioned technical scheme, the forging and pressing of being convenient for more under this temperature has improved the efficiency of forging and pressing.

The present invention in a preferred example may be further configured to: the round making die is provided with a forging hole, and the forging hole sequentially comprises a square hole, an octagonal hole, a hexagonal hole and a round hole from top to bottom.

Through adopting above-mentioned technical scheme, the square billet passes the forging hole under the effect of press, and the square billet warp in proper order for octagon prism, hexagonal pyramid, becomes the cylinder at last, makes the square billet progressively deform, reduces the deformation volume of square billet deformation at every turn, avoids deformation excess to lead to the square billet fracture.

The present invention in a preferred example may be further configured to: the contained angle in octagon hole and the side parallel and level in quad slit, the contained angle in sixteen limit hole and the side parallel and level in octagon hole, the round hole is the inscribed circle in sixteen limit hole.

By adopting the technical scheme, the areas of the square hole, the octagonal hole, the sixteen-sided hole and the round hole are gradually reduced, so that the square billet is continuously compressed in the radial direction in the process of passing through the forging hole, the defects of casting state looseness and the like generated in the smelting process of metal are eliminated, the microstructure is optimized, and the mechanical property of the billet is improved.

The present invention in a preferred example may be further configured to: be provided with four first direction inclined planes between quad slit and the octagon hole, first direction inclined plane is isosceles triangle, and its apex angle is contradicted in the edges and corners department of quad slit, and its two base angles are located two adjacent edges and corners in octagon hole respectively.

Through adopting above-mentioned technical scheme, utilize first direction inclined plane to lead for the blank to make square blank extrude gradually and be eight prism shape, make the square billet progressively deform, avoid deformation speed too fast and lead to the square billet fracture.

The present invention in a preferred example may be further configured to: eight second direction inclined planes are arranged between the octagonal hole and the hexadecimal hole, the second direction inclined planes are isosceles triangles, vertex angles of the second direction inclined planes are butted at edges and corners of the octagonal hole, and two base angles of the second direction inclined planes are respectively located at two adjacent edges and corners of the hexadecimal hole.

By adopting the technical scheme, the second guide inclined plane is used for guiding the blank, and the octagonal-prism-shaped blank is gradually extruded into a sixteen-prism shape, so that the square blank is gradually deformed, and the square blank is prevented from being broken due to the fact that the deformation speed is too high.

The present invention in a preferred example may be further configured to: sixteen third direction inclined planes are arranged between the sixteen-edge-shaped hole and the round hole, the third direction inclined planes are arc surfaces in the shape of an isosceles triangle, the vertex angles of the third direction inclined planes are abutted to the edges of the sixteen-edge-shaped hole, and two base angles of the third direction inclined planes are located on the side walls of the round holes.

By adopting the technical scheme, the third guide inclined plane is used for guiding the blank, and the sixteen-prism-shaped blank is gradually extruded to be cylindrical, so that the blank is gradually deformed, and the blank is prevented from being broken due to the excessively high deformation speed.

The present invention in a preferred example may be further configured to: in step S4, the center of the blank is hammered after upsetting to reduce the thickness of the center of the blank, and then the center of the blank is punched.

Through adopting above-mentioned technical scheme for the clout that falls of punching a hole thickness reduces, thereby has reached the weight that has reduced the clout, has improved the utilization ratio of raw materials, the manufacturing cost who reduces.

The present invention in a preferred example may be further configured to: in step S5, the ring rolling is divided into a primary ring rolling machine and a secondary ring rolling machine, the primary ring rolling machine is a vertical ring rolling machine, the vertical ring rolling machine is used to enlarge the central hole of the blank, and the secondary ring rolling machine is a horizontal ring rolling machine to roll the axial end face of the blank.

Through adopting above-mentioned technical scheme, utilize once, the secondary ring rolls the ring to the work piece, the ring rolls the work piece for the first time and carries out the reaming, and the secondary ring rolls the thickness of blank and controls, makes the terminal surface of blank more level and more smooth, need make things convenient for the processing that the back needs to the flange terminal surface after reducing.

In summary, the invention includes at least one of the following beneficial technical effects:

firstly, when a square blank is forged into a cylinder, a round die is used for rounding a square blank, the square blank is placed on the round die, and then a press is used for applying pressure to the square blank to form the square blank into round steel, so that the square blank does not need to be rotated for many times, the forging of the round steel is realized, the operation is simplified, the time is saved, and the forging efficiency is improved;

secondly, a forging hole is formed in the round making die, the forging hole sequentially comprises a square hole, an octagonal hole, a sixteen-sided hole and a round hole from top to bottom, a square billet penetrates through the forging hole under the pressure of a press machine, the square billet is gradually deformed into an octagonal prism and a hexagonal pyramid at one time and finally becomes a cylinder, the square billet is gradually deformed, the deformation amount of each deformation of the square billet is reduced, and the square billet is prevented from being broken due to excessive deformation;

and thirdly, the ring rolling is divided into a ring rolling and a secondary ring rolling, the ring rolling is carried out on the workpiece by utilizing the primary ring rolling and the secondary ring rolling, the primary ring rolling is used for reaming the workpiece, the secondary ring rolling is used for controlling the thickness of the blank, the end surface of the blank is more smooth, the flange end surface is required to be processed after the reduction, and the processing required after the flange end surface is convenient.

Drawings

FIG. 1 is a schematic step diagram of the present embodiment;

FIG. 2 is a schematic structural diagram of a circle-making mold according to the present embodiment;

fig. 3 is a sectional view of the present embodiment for showing a forged hole.

Reference numerals: 100. a rounding die; 101. forging a hole; 102. a square hole; 103. an octagonal hole; 104. a sixteen-sided aperture; 105. a circular hole; 106. a first guide slope; 107. a second guide slope; 108. a third guide slope; 109. and (6) taking the material port.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Example (b): as shown in fig. 1, in order to implement the flange forging process disclosed in the present invention, step S1: and cutting, namely cutting the strip-shaped blank with the square cross section into a plurality of square blanks by using a band sawing machine. The weight of each square billet is 1.05-1.10 times of the weight of the qualified flange. The required weight can be converted into the required volume of the square billet through a relational formula of density, mass and volume, then the length of the required square billet is calculated through the sectional area of the square billet, and the square billet with the required mass is cut according to the length.

And step S2, heating, namely placing the square billet in a natural gas furnace for heating, wherein the temperature of the natural gas furnace is 1180-1220 ℃, and the temperature of the square billet is enabled to be higher than the recrystallization temperature and lower than the solidus temperature.

And step S3, rounding, in which the square billet is placed in a rounding die 100 (see fig. 2), and the square billet is forged into a cylindrical billet.

And step S4, upsetting the round blank by using a clamping rod hammer at the free end. The axial pressure is applied to the blank by the clamping rod hammer, so that the diameter of the blank is increased, and the axial length of the blank is reduced. And hammering the center of the blank by using an air hammer after upsetting to reduce the thickness of the center of the blank, and then punching the center of the blank by using a punch. The thickness of the punched residual material is thinner, so that the weight of the residual material is reduced, the utilization rate of raw materials is improved, and the production cost is reduced.

Step S5: and (3) rolling the ring, wherein the rolling ring is divided into a primary rolling ring and a secondary rolling ring, the primary rolling ring adopts a vertical ring rolling machine, the central hole of the workpiece is enlarged by using the vertical ring rolling machine, and the axial end face of the blank forms a bulge due to the extrusion of the inner hole wall and the outer wall in the reaming process. The secondary ring rolling adopts a horizontal ring rolling machine to roll the end face of the blank, so that the end face of the blank is smoother, and the bulge left on the end face of the flange during primary ring rolling is rolled, thereby facilitating the processing required later.

Step S6: and annealing, namely placing the blank in a resistance furnace, and carrying out spheroidizing annealing on the blank. Spheroidizing annealing can obtain a spheroidized structure similar to granular pearlite, and the spheroidized structure not only has better plasticity and toughness than a flaky structure, but also has slightly lower hardness. When a workpiece having a spheroidized structure is cut, the cutter avoids cutting hard and brittle cementite and passes through soft ferrite, thereby prolonging the service life of the cutter, improving the machinability of steel to reduce the hardness, and improving the machinability.

Step S7: and turning, namely turning the flange by using a lathe.

As shown in fig. 2 and 3, the circle making die 100 is mounted on a table of the electro-hydraulic hammer, a forging hole 101 is formed in an upper end surface of the circle making die 100, the forging hole 101 is a through hole, and the forging hole 101 sequentially includes a square hole 102, an octagonal hole 103, a hexadecimal hole 104, and a round hole 105 from top to bottom. The included angle in octagonal hole 103 is flush with the side of square hole 102, the included angle in hexadecimal hole 104 is flush with the side of octagonal hole 103, and round hole 105 is the inscribed circle in hexadecimal hole 104. The square billet is placed at the square hole 102, and the square billet passes through the forging hole 101 by applying vertical downward pressure on the square billet through the electro-hydraulic hammer. When the square billet passes through the forging hole 101, the square billet is gradually and sequentially deformed into an octagonal prism and a hexagonal pyramid, and finally becomes a cylinder. The bottom of the circle making die 100 is provided with a horizontally arranged material taking opening 109, the material taking opening 109 is communicated with the round hole 105, and the width of the material taking opening 109 is larger than the diameter of the round hole and is used for taking out the cylindrical blank from the circle making die 100.

As shown in fig. 3, four first guiding inclined planes 106 are fixedly connected between the square hole 102 and the octagonal hole 103, the first guiding inclined planes 106 are isosceles triangles, the vertex angles thereof are abutted against the edge angles of the square hole 102, and the two base angles thereof are respectively located at two adjacent edge angles of the octagonal hole 103. Eight second direction inclined planes 107 are fixedly connected between octagonal hole 103 and hexadecimal hole 104, and second direction inclined plane 107 is isosceles triangle, and its apex angle is contradicted in octagonal hole 103's edges and corners, and its two base angles are located two adjacent edges and corners in hexadecimal hole 104 respectively. A third guide ramp 108 is provided between the sixteen aperture 104 and the circular aperture 105. The third guiding inclined plane 108 is an arc surface in the shape of an isosceles triangle, the vertex angle of the third guiding inclined plane 108 is abutted against the edge angle of the hexadecagon hole 104, and the two base angles are located on the side wall of the round hole 105. The first guide inclined surface 106, the second guide inclined surface 107 and the third guide inclined surface 108 are used for guiding the blank, and the square blank is gradually extruded to be cylindrical, so that the blank is gradually deformed, and the blank is prevented from being broken due to the fact that the blank deformation speed is too high.

The specific working principle of this embodiment is as follows: utilize system circle mould to realize the system circle of square billet, place the square billet on system circle mould, then utilize the press to exert pressure to the square billet, make its shaping be the round steel to need not to rotate the square billet many times, just realized the forging of round steel, simplified the operation, saved the time, provided forged efficiency.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. A flange forging process is characterized in that: the method comprises the following steps: step S1: cutting, namely cutting the strip-shaped blank with the square cross section into a plurality of square blanks; step S2: heating, namely placing the square billet in a heating furnace for heating, so that the temperature of the square billet is higher than the recrystallization temperature and lower than the temperature of a solidus line; step S3: rounding, namely placing a square billet in a rounding die (100), and forging the square billet into a cylindrical billet; step S4: free forging, namely upsetting the heated blank by using a press machine, and then punching the blank by using a punch; s5: ring rolling, namely mounting the blank on a ring rolling machine for ring rolling, and enlarging the central hole of the blank; step S6: annealing, namely placing the blank in a resistance furnace for annealing; step S7, turning, namely turning the flange by using a lathe; the round making die (100) is provided with a forging hole (101), and the forging hole (101) sequentially comprises a square hole (102), an octagonal hole (103), a hexadecagon hole (104) and a round hole (105) from top to bottom; the included angle of the octagonal hole (103) is flush with the side of the square hole (102), the included angle of the dodecagonal hole (104) is flush with the side of the octagonal hole (103), and the round hole (105) is an inscribed circle of the hexadecagonal hole (104); four first guide inclined planes (106) are arranged between the square hole (102) and the octagonal hole (103), the first guide inclined planes (106) are isosceles triangles, the vertex angles of the first guide inclined planes are abutted against the edge angles of the square hole (102), and the two base angles of the first guide inclined planes are respectively positioned at two adjacent edge angles of the octagonal hole (103); eight second guide inclined planes (107) are arranged between the octagonal hole (103) and the hexadecimal hole (104), the second guide inclined planes (107) are isosceles triangles, the vertex angles of the second guide inclined planes are butted with the edge angles of the octagonal hole (103), and the two base angles of the second guide inclined planes are respectively positioned at two adjacent edge angles of the hexadecimal hole (104); sixteen third direction inclined plane (108) are set up between sixteen limit shape hole (104) and round hole (105), the cambered surface of third direction inclined plane (108) for being isosceles triangle shape, third direction inclined plane (108) apex angle is contradicted in the edges and corners department of sixteen limit shape hole (104), and its two base angles all are located the lateral wall department of round hole (105).

2. A flange forging process according to claim 1, wherein: in step S1, the weight of the square billet before cutting is 1.05 to 1.10 times the weight of the qualified flange in step S7.

3. A flange forging process according to claim 1, wherein: in step S4, the blank is heated by a natural gas heating furnace, wherein the temperature of the natural gas heating furnace is 1180-1220 ℃.

4. A flange forging process according to claim 1, wherein: in step S4, the center of the blank is hammered after upsetting to reduce the thickness of the center of the blank, and then the center of the blank is punched.

5. A flange forging process according to claim 1, wherein: in step S5, the ring rolling is divided into a primary ring rolling machine and a secondary ring rolling machine, the primary ring rolling machine is a vertical ring rolling machine, the vertical ring rolling machine is used to enlarge the central hole of the blank, and the secondary ring rolling machine is a horizontal ring rolling machine to roll the axial end face of the blank.