JP2010188355A - Method for forging short cylindrical part with flange or the like - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a short cylindrical part with a flange or the like by a forging machine with small pressurizing tonnage in hot-forging even in a small lot while reducing manufacturing cost by reducing material cost and saving energy. <P>SOLUTION: After forming a short columnar member by cutting a rod-shaped steel stock, an end face of the short columnar member is pressed by the hot-forging machine to form a disk-shaped member, and successively, in a stage before a step for forming into a short cylindrical shape with the flange by a mold, a circular recessed portion is formed at a center part of the disk-shaped member, and also a bottom plate portion of the circular recessed portion is punched out to form a disk-shaped member with a hole, thereafter pressed by a die and punch, and the short cylindrical part with the flange is formed by bending forging processing of a peripheral part of the hole downward, and bending forming of a lower side short cylindrical part. In addition to thereabove, a simultaneously formed upper side short cylindrical part are divided into up and down to form a part for inner ring and a part for outer ring of a bearing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a short cylindrical part with a flange or the like, that is, a product having a flange part on one side and having a short cylindrical part on the other side, or divided into two from the same shape, for example, for inner and outer rings of bearings. This is related to the improvement of the method of manufacturing parts such as these from round steel by forging, and is characterized by reducing material costs and saving energy.

  For example, there are products manufactured from steel plates (see, for example, JP-A-2007-170586) and products manufactured from steel pipes (see, for example, JP-A-2007-130673). The invention is a method for easily, quickly and economically manufacturing round steel materials by forging.

  As a method of manufacturing by forging from a round bar-shaped steel material, for example, a rod-shaped material made of steel material is cut to a predetermined size to form a short columnar member, which is press-formed into a pancake disk-shaped member by hot forging. After that, by cold forging, pressurizing with a mold and forging to form a bottomed short cylindrical member with a flange (see, for example, FIG. 21 and FIG. 22), and then pulling out the bottom plate portion with a flange Some formed a short cylindrical part, and then performed an annealing treatment or the like.

  In the case of manufacturing the outer ring and the inner ring part of the bearing, after forming a short cylindrical part with a flange in the same manner as described above (see, for example, FIGS. 23 and 24), it is separated into upper and lower parts for the outer ring. And a short cylindrical portion for the inner ring. In any of the above cases, it is manufactured by a combination of hot forging and cold forging.

JP-A-2005-205457 JP-A-2005-211929 JP-A-2005-27034 JP 2005-288505 A JP 2002-172450 A JP 59-039443 JP 07-009064 A

However, the conventional methods described above and the methods described in the prior art documents have the following problems.
B) Since a process using cold forging is used, a large forging machine having a large pressure tonnage is required. Therefore, the manufacturing cost is increased, the life of the mold is short, and the yield is also deteriorated. This tendency is stronger in products having a larger wall thickness, products having longer collars and short cylindrical portions.

  B) In order to use both hot forging and cold forging processing, it is necessary to install both forging machines or to provide a forging machine with multiple mechanisms. In addition, reheating is necessary for the subsequent annealing treatment, which is contrary to energy saving and difficult to produce in a small lot.

  C) When the short cylindrical portion has been press-formed under the collar, the bottom portion is bottomed (see, for example, FIGS. 21, 22, 23, and 24), and then the bottom portion of the short cylindrical portion is extracted. ing. During the forging of the short cylindrical portion, the short cylindrical portion is connected by the bottom plate portion, so that the steel material does not move well during pressurization, and resistance to the flow prevents smooth forming. Products with larger wall thickness and longer cylindrical parts tend to have such a tendency. As described above, a large pressure tonnage applied to the mold is required, and the forging machine has to be enlarged in this respect as well.

  D) Since the bottom part is punched after forging the short cylindrical part with a collar with a bottom, there is not a lot of loss of the steel material to be removed at that time. There was also a waste of energy.

  E) In order to facilitate forging forming on the other side, short cylindrical parts with a flange, the applicant first proposed a method of forming holes in the bottom plate portion of the disk-shaped member in advance before forging. (Japanese Patent Application No. 2007-207321). However, since the holes to be formed there also need a certain size for improving the flow of meat in the next forging, there is little waste of the steel material that is removed even if it is not as much as before, Since the heat treatment is performed in the process until the hole is formed, there is a waste of energy, and there remains a problem in terms of energy saving.

  An object of the present invention is to solve the problems of the conventional forging method. That is, the object of the present invention is to manufacture a part having a bowl-shaped part on one side and a short cylindrical part on the other side, or manufacturing the parts for bearing outer ring and inner ring parts by relatively small processing. Manufactured with a compact forging machine with a pressure tonnage to reduce manufacturing costs, manufacture only by hot forging, save energy, enable manufacturing in small lots, and punch the bottom plate It is an object of the present invention to provide a manufacturing method that can reduce the size of the holes, reduce the amount of material to be removed there, reduce the energy loss associated with the heat treatment, and reduce the cost from this aspect.

A The first forging method of the short cylindrical part with a flange according to the present invention is:
After forming the short columnar member 2 by cutting the steel rod-shaped material 1 into a predetermined length,
By hot forging machine,
Pressurizing the end face of the short cylindrical member 2 to form a pancake-like disk-shaped member 3,
Next, in the stage before the process of pressure forming into a short cylindrical shape with a flange,
A circular recess 4 is formed at the center of the disk-shaped member 3 and a hole 5 is punched out at the center of the bottom plate portion of the circular recess 4 to form a disk-shaped member 6 with a hole.
Thereafter, the disk-shaped member 6 with holes is pressed with a die 7 and a punch 8, the peripheral portion 9 of the hole 5 is bent downward, and the short cylindrical portion 10 is bent downward. The short cylindrical part 11 with a flange is formed.

B Second of the forging method of the short cylindrical part with a flange according to the present invention,
After forming the short columnar member 2 by cutting the steel rod-shaped material 1 into a predetermined length,
By hot forging machine,
Pressurizing the end face of the short cylindrical member 2 to form a pancake-like disk-shaped member 3,
Next, in the stage before the process of pressure forming into a short cylindrical shape with a flange,
A circular recess 4 is formed at the center of the disk-shaped member 3, and a hole 5 is punched into the center of the bottom plate portion of the circular recess 4 to form a disk-shaped member 6 with a hole.
Thereafter, the disk-shaped member 6 with a hole is pressurized with a die 7 and a punch 8, the peripheral portion 9 of the hole 6 is bent downward and forged, and the lower short cylindrical portion 12 is bent and simultaneously formed. An upper short cylindrical portion 14 is formed by extending the upper peripheral portion 13 of the disk-shaped member 6 with a hole upward,
Further, the inner ring part 15 and the outer ring part 16 of the bearing are formed by separating them in the vicinity of the boundary between the lower short cylindrical part 12 and the upper short cylindrical part 14. It is.

  A The first feature of the present invention is that a hole 5 is formed in the center of the disk-shaped member 3 in advance before the step of pressure forming the pancake-shaped disk-shaped member 3 into a short cylindrical shape with a hook. Then, the disk-shaped member 6 with a hole is formed, and thereafter, this is pressure-formed toward the short cylindrical part with a flange.

Therefore, a) the pressure tonnage at the time of molding can be reduced, the forging machine can be downsized, and the yield can be improved.
That is, in the step of pressure-forming the disk-shaped member 3 into a short cylindrical shape with a hook, conventionally, as shown in FIGS. 21, 22, 23 and 24, the short cylindrical portion is the bottom plate of the lower part during the molding. Since the portions 17 are integrally connected, the steel material does not move well even when pressed with a mold, and resistance to the flow prevents resistance to form smoothly. As a result, it was necessary to increase the pressure tonnage applied to the mold, and it was necessary to use a large forging machine.

  However, in the forging method of the present invention, the recess 4 is formed in the disk-shaped member 3 and the hole 5 is punched in the bottom plate portion before the step of forming the short cylindrical portion in the disk-shaped member 3. It is formed (see, for example, FIGS. 3 and 13). For this reason, since the short cylindrical portion is not connected at the lower portion during pressure molding (see, for example, FIGS. 6 and 16), the meat of the steel material easily moves during pressure molding, and is easily formed into a short cylindrical shape. Thus, the pressure tonnage can be reduced at the time of pressure forming, the forging machine can be reduced in size, the manufacturing cost can be reduced by energy saving, and the yield can be improved because the forming process proceeds without difficulty.

B) In addition to energy saving, small lot production is also facilitated.
That is, in the conventional method, the short columnar member 2 is first formed into the disk-like member 3 by hot forging, and is pressed with a die by cold forging to form a short cylindrical part with a flange, and then annealed. Had gone. Therefore, it was necessary to perform heat treatment at the time of the initial hot treatment and at the time of the subsequent annealing treatment.

  On the other hand, in the present invention, all the subsequent steps from the short cylindrical member 2 may be performed by hot forging, and can be manufactured by only a hot-working forging machine. There is no need to heat-treat. In this respect as well, the manufacturing cost can be reduced, energy saving can be achieved, and it is also suitable for small lot production.

  B The second feature of the present invention is that the peripheral portion 9 of the holed disk-shaped member 6 to the hole 5 is bent and forged by a die 7 and a punch 8 instead of normal forging. The cylindrical portion 10 is formed by bending to form a short cylindrical part 11 with a flange.

  Therefore, in the present invention, it is possible to manufacture with a forging machine having a relatively small pressure tonnage, to reduce the manufacturing cost and improve the yield, and to manufacture only by hot forging.

  That is, in the conventional manufacturing method, as described above, the forging machine needs to have a large pressure tonnage, which increases the manufacturing cost, shortens the life of the mold, and deteriorates the yield. On the other hand, in the present invention, the peripheral portion 9 of the central hole 5 of the disk-shaped member 3 is bent and forged downward, so that the peripheral portion 9 is bent smoothly and smoothly downward. Therefore, the short cylindrical part 11 with a flange can be manufactured easily and quickly, with energy saving and relatively small force.

    B) Furthermore, the present invention can reduce the amount of steel material to be removed as an unnecessary part in the manufacturing process, eliminate waste of material costs, and reduce costs.

  That is, in the present invention, as described above, the peripheral portion 9 of the hole 5 formed in the holed disk-like member 6 is bent by bending forging unlike the conventional normal forging, and the short cylindrical portions 10 and 12 are bent downward. Since the molding is performed, the holes 5 formed in advance may be smaller than the conventional method.

  Therefore, compared with the conventional punching of the bottom of the short cylindrical part after normal forging, and the prior formation of the hole before the forging proposed by the applicant, the steel material is not required in the manufacturing process. As a result, the volume to be removed is reduced, and the material cost can be reduced. In addition, since the volume of the portion removed as an unnecessary portion is small, energy used for heat treatment including the portion before the formation of the hole is small, and energy saving can be achieved.

    B) In addition, according to the present invention, parts for the inner ring and the outer ring of the bearing can be manufactured easily and quickly. That is, in the present invention, similarly to the above, the hole-shaped disk-like member 6 is bent and forged by the die 7 and the punch 8 so that the peripheral portion 9 of the hole 5 is bent downward, thereby lowering the lower short cylindrical portion 12 downward. At the same time, the upper short cylindrical portion 14 is formed by extending the upper peripheral portion of the cylindrical member 6 with a hole upward.

  As a result, a part having the lower short cylindrical portion 12 and the upper short cylindrical portion 14 is easily and quickly formed, and thereafter, the part is formed near the boundary between the lower short cylindrical portion 12 and the upper short cylindrical portion 14. Thus, the inner ring parts 15 and 1 and the outer ring part 16 of the bearing can be formed.

It is a perspective view which shows the short columnar member used in the 1st Example of the forging method of the short cylindrical part with a flange etc. which concern on this invention. It is a perspective view which shows the disk shaped member formed from what was shown in FIG. It is a perspective view which shows the state which formed the recess and the hole in what was shown in FIG. FIG. 4 is a longitudinal front view of the state shown in FIG. 3 in a state where pressure is formed with a die and a punch. FIG. 5 is a longitudinal front view showing a state where bending pressure is started from the state shown in FIG. 4. FIG. 6 is a longitudinal front view showing a state in which bending pressure has advanced from the state shown in FIG. 5. FIG. 7 is a longitudinal front view of a state where bending pressure is further advanced from the state shown in FIG. 6. FIG. 8 is a longitudinal front view of a state in which bending pressure is further increased from the state illustrated in FIG. 7 and a short cylindrical portion is being formed. FIG. 9 is a longitudinal front view of a state where bending pressure further proceeds from the state shown in FIG. 8 and a short cylindrical portion is formed. It is a partially longitudinal front view which shows the short cylindrical part with a flange formed by the 1st Example of this invention. It is a perspective view which shows the short columnar member used with the 2nd Example of the forging method of the short cylindrical part with a flange concerning this invention. It is a perspective view which shows the disk shaped member formed from what was shown in FIG. It is a perspective view which shows the state which formed the recess and the hole in what was shown in FIG. It is a vertical front view of the state which is going to press-form what is shown in FIG. 13 with a die | dye and a punch. It is a vertical front view of the state which started bending and pressing from the state shown in FIG. FIG. 16 is a longitudinal front view showing a state in which bending pressure has advanced from the state shown in FIG. 15. FIG. 17 is a longitudinal front view showing a state in which bending pressure is further advanced from the state shown in FIG. 16 and a lower short cylindrical portion is being formed. FIG. 18 is a longitudinal front view of a state in which the lower short cylindrical portion is formed from the state shown in FIG. 17 and the upper short cylindrical portion is formed. FIG. 19 is a longitudinal front view of a member having a lower short cylindrical portion and an upper short cylindrical portion shown in FIG. 18. It is a partial longitudinal front view which shows the components for inner rings and the components for outer rings formed by the 2nd Example of this invention. It is a vertical front view of the state which press-forms without forming a hole in a disk shaped member as a prior art example. FIG. 22 is a partially longitudinal front view of a short cylindrical part with a flange formed by the one shown in FIG. 21. As another conventional example, it is a longitudinal front view of a state where pressure is formed without forming a hole in a disk-shaped member. FIG. 24 is a partially longitudinal front view of a flanged short cylindrical part formed of the one shown in FIG. 23.

  As described above, the present invention cuts the rod-shaped material 1 made of a steel material into short cylindrical members 2 and then forms the pancake-like disc-like member 3 formed by pressing the pan-like disc-like member 3 at a stage before the step of pressure forming. A hole 5 is punched into a recess 4 formed in the member 3 in advance, and then the disk-shaped member 6 with a hole is bent and forged by a die 7 and a punch 8 to thereby form a short cylindrical part with a flange 10, 15 and the like. , 16 can be formed, and energy saving and cost reduction can be realized.

  1 to 10 show a first embodiment of a forging method for a flanged short cylindrical part or the like according to the present invention.

  Here, a high carbon chromium bearing steel material is used as the round bar-shaped steel material, and the short columnar member 2 is formed by cutting into a predetermined dimension (see FIG. 1). Here, the predetermined dimension is determined in consideration of an outer diameter, an inner diameter, a thickness, a height, and the like of each part such as a short cylindrical part with a flange.

  Next, the short cylindrical member 2 is all processed by hot forging. The hot processing temperature is about 1100 ° C. in this case. First, from both end faces using a press machine. Pressure is applied to form a pancake disk-shaped member 3 (see FIG. 2).

  Next, a circular recess 4 is formed in the center of the disk-shaped member 3 (see FIG. 3). If the thickness of the lower short cylindrical portion 12 is insufficient later, the bottom portion is swelled so that the lower portion of the wall is increased, while the thickness of the upper flange portion is increased. If there is a shortage, the shape of the upper part of the disk-shaped member 3 is increased.

  Subsequently, at the stage before the step of pressure forming with the die 7 and the punch 8, the center of the peripheral portion 9 of the hole 5 of the circular recess 4 is punched to form the disk-shaped member 6 with the hole 5. (See FIG. 3 above). The hole 5 here is different from the conventional normal forging, and the next processing molding is bending forging to bend downward to form the short cylindrical portion 10, so that its size is larger than that of the conventional one. The size may be small. The size of the hole 5 is set so that the volume of the peripheral portion 9 of the hole 5 of the recess 4 is the same as the volume of the short cylindrical portion 10 after molding.

  Thereafter, the disk-like member 6 with a hole is supported by a die 7 (see FIG. 4), and the peripheral portion 9 of the hole 5 is pressurized with a punch 8 having a cylindrical protrusion (FIGS. 5, 6, and 7). (See FIG. 8 and FIG. 9). In this forming step, as described above, the hole 5 is formed in the center of the disk-shaped member 3 in advance before the step, and the peripheral portion 9 is bent and forged downward by the die 7 and the punch 8.

  Therefore, unlike the conventional normal forging, the meat of the peripheral portion 9 is smoothly bent downward without receiving a large resistance (see FIGS. 5, 6, and 7), and follows the shape of the die 7 and the punch 8. Bending forging is performed, the downward short cylindrical portion 10 is bent (see FIGS. 8 and 9), and a short cylindrical part 11 with a flange as shown in FIG. 10 is formed. .

  FIGS. 11 to 20 show a case where inner ring parts and outer ring parts of a bearing are manufactured as one of the manufacture of a short cylindrical part with a flange and the like. Since the first half of the process has many parts in common with the above, the common parts will be outlined.

  As the steel rod-shaped material 1, the same bearing steel as described above is used here, and a short columnar member 2 is formed from the rod-shaped material 1 (see FIG. 11), and all subsequent processing is performed by hot forging. First, a pancake-like disk-shaped member 3 is formed (see FIG. 12).

  Next, the center of the peripheral portion 9 of the hole 5 of the recess 4 is punched out before the step of forming the recess 4 in the disk-shaped member 3 and subsequently press-molding with the die 7 and the punch 8. It forms in the disk shaped member 6 with the hole 5 (refer FIG. 13). Unlike the case of the conventional normal forging, the hole 5 here is also formed by bending forging, so that the hole 5 may be smaller than the conventional one as will be described later. The volume of the peripheral portion 9 of the fourth hole 5 is set to be the same as the volume of the short cylindrical portion 10 after molding.

  Subsequently, the disk-like member 6 with a hole is pressed with a die 7 and a punch 8 (see FIGS. 14, 15, and 16), and the peripheral portion 9 of the hole 5 is bent downward by bending forging. Then, the lower short cylindrical portion 12 is formed (FIGS. 17 and 18). Also in this forming process, the disk-shaped member 3 is formed with a hole 5 in the center in advance before the process as described above, and the peripheral portion 9 is bent and forged by a die 7 and a punch 8. Accordingly, the peripheral portion 9 of the hole 5 is smoothly bent downward, and the lower short cylindrical portion 12 is formed (see FIG. 18).

  At the same time, the upper peripheral portion 13 of the disk-shaped member 3 is extended upward by the die 7 and the upper stage portion of the punch 8, and the upper short cylindrical portion 14 is formed (FIGS. 18, 18). 19).

  After that, a component having the lower short cylindrical portion 12 and the upper short cylindrical portion 14 (see FIG. 19) is moved up and down in the vicinity of the boundary between the lower short cylindrical portion 12 and the upper short cylindrical portion 14. What is necessary is just to isolate | separate. Thus, the lower short cylindrical portion 12 is formed in the inner ring component 15 of the bearing, and the upper short cylindrical portion 14 is formed in the outer ring component 16 (see FIG. 20).

  The size of the hole 5 formed in the disk-shaped member varies depending on the size of the product to be manufactured. In this embodiment, the outer ring component 16 has an outer diameter of 117 mm, an inner diameter of 107 mm, and a height of 20 mm. The inner ring part 15 was manufactured with an outer diameter of 96 mm, an inner diameter of 72 mm, and a height of 26 mm. In this case, since the bending pressure molding is used in the present invention, the required size of the hole 5 may be 50 mm, and the weight of the portion punched and removed by the hole 5 was 135 g. On the other hand, when a product of the same size is manufactured by conventional normal forging, the hole should have a diameter of about 72 mm even if the hole is made before pressure molding. The weight of the portion punched and removed by the hole was 276 g. As a result, in the embodiment of the present invention, it was clarified that the weight of the steel material removed as unnecessary is only about one half, and the material cost can be reduced.

  Needless to say, each of the above manufacturing methods is not limited to the taper bearing but is also substantially the same when a radial bearing is manufactured. The numerical values indicating the material, temperature, dimensions, etc. shown above are merely examples, and the present invention is not limited thereto.

  The present invention provides a short cylindrical part with a flange, that is, a product having a flange part on one side and a short cylindrical part on the other side, or separated and cut from a similar shape, for example, for inner and outer rings of bearings. These parts can be widely applied when forging from round steel materials by forging, and material costs can be reduced and energy can be saved.

1-bar material 2-short cylindrical member 3-disk-shaped member 4-recess 5-hole 6-disk-shaped member 7-dice 8-punch 9-peripheral part 10-short cylindrical part 11-short with flange Cylindrical component 12-Lower short cylindrical portion 13-Upper peripheral portion 14-Upper short cylindrical portion 15-Inner ring component 16-Outer ring component 17-Bottom plate portion

Claims (4)

After forming the short cylindrical member 2 by cutting the steel rod-shaped material 1 into a predetermined length,
By hot forging machine,
The end surface of the short cylindrical member 2 is pressurized to form a pancake-like disk-shaped member 3,
Next, in the stage before the process of pressure forming into a short cylindrical shape with a flange,
A circular recess 4 is formed in the center of the disc-shaped member 3 and a hole 5 is punched out in the center of the bottom plate portion of the circular recess 4 to form a disc-shaped member 6 with a hole.
Thereafter, the disk-shaped member 6 with holes is pressed with a die 7 and a punch 8, the peripheral portion 9 of the holes 5 is bent downward, and the short cylindrical portion 10 is bent downward. A forging method for a short cylindrical part with a flange, etc., characterized in that it is formed on the short cylindrical part 11 with a flange. After forming the short columnar member 2 by cutting the steel rod-shaped material 1 into a predetermined length,
By hot forging machine,
Pressurizing the end face of the short cylindrical member 2 to form a pancake-like disk-shaped member 3,
Next, in the stage before the process of pressure forming into a short cylindrical shape with a flange,
A circular recess 4 is formed at the center of the disk-shaped member 3, and a hole 5 is punched into the center of the bottom plate portion of the circular recess 4 to form a disk-shaped member 6 with a hole.
Thereafter, the disk-shaped member 6 with a hole is pressed with a die 7 and a punch 8, the peripheral portion 9 of the hole 5 is bent and forged, and the lower short cylindrical portion 12 is bent and formed at the same time. An upper short cylindrical portion 14 is formed by extending the upper peripheral portion 13 of the disk-shaped member 6 with a hole upward,
In addition, the inner ring part 15 and the outer ring part 16 of the bearing are formed by separating the upper and lower parts in the vicinity of the boundary between the lower short cylindrical part 12 and the upper short cylindrical part 14. A forging method for a short cylindrical part with a flange, etc. When there is a possibility that the thickness of the formed lower short cylindrical portion 12 is insufficient, at the stage where the recess 4 and the hole 5 are formed in the pancake-like disk-shaped member 3, The forging method of a short cylindrical part with a flange or the like according to claim 2, wherein the bottom part is swelled so as to increase meat. When there is a possibility that the thickness of the formed upper short cylindrical portion 14 for the outer ring is insufficient, the pancake-like disk-shaped member 3 is pressurized to form the recess 4 in the central portion. The forging method for a short cylindrical part with a flange according to claim 2, wherein the upper peripheral part 12 of the disk-shaped member 3 is thick.

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