JP2006043770A - Method for producing formed product, die for forging formed product, formed product and forging production system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the yield on a producing system by reducing the defective product in the visual examination. <P>SOLUTION: In a method for producing a formed product, by which the formed product provided with a cylindrical or columnar center part 92 and at least an enlarged diameter part continued from this center part 92 is formed and larger than the center part in the plane view from a preformed material 90, when the preformed material 90 is set in a formed cavity 4 surrounded with an upper die 2 and a lower die 3, in the preformed material 90, the center portion 920 for forming to the center part after forming, is abutted on the lower die 3 so as to form a prescribed gap L1 in the push-out direction at the gap between the enlarged diameter portion 910 for forming the enlarged diameter part after forming and the lower die 3, and a process for producing the formed product by pushing out the preformed material 90 with the upper die from the above setting state, is contained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a molded product manufacturing method and a molded product for manufacturing a molded product including at least a cylindrical or columnar central portion and a diameter-enlarged portion continuous from the central portion and having a diameter larger than that of the central portion in plan view. The present invention relates to a forging die, a molded product, and a forging production system used when forging a product.

  Forging is one of the plastic working methods for manufacturing machine parts and the like. Forging is a process of forming a mold by placing a pair of upper and lower molds in a forging device, placing a mold in the mold, moving the upper mold and applying a load to the mold. It is used to manufacture molded products.

  Production by forging is generally continuous production in which everything from the introduction of a shaped material to a forging device to the discharge of a molded product from the forging device is automated. In this continuous production, for example, as shown in the figure, the base material 105 is put into a mold used for molding (FIG. 17A), pressure-molded (FIG. 17B), and after molding The mold 102 is raised, and the molded product remaining in the die 133 is lifted above the die 133 by a knock-out pin (FIG. 17C), and is taken out of the forging device by the carry-out device.

  When the molded product 105 has a complicated shape, it is difficult to obtain a final shape by one molding, and therefore, a method of molding the final shape by repeating the above steps a plurality of times is used.

  And this shaping | molding by forging is a shaping | molding provided with the cylindrical or columnar center part 201 as shown, for example in FIG. 18, and the enlarged diameter part 202 which is continuous from the center part 201 and whose diameter is larger than a center part by planar view. It is generally applied also when manufacturing the product 200.

  However, when the molded product 200 having the above shape is manufactured, in the conventional construction method, “offset wrinkles” are generated in the enlarged diameter portion (flange portion) 202. As shown in FIG. 18, the side wrinkles are those in which unevenness occurs in the surface layer as a result of the flow of the material. For example, the side surface of the flange contour shape overlaps with the ridge line portion of the CAD in the molding process, End up. This side wrinkle is confirmed by an appearance inspection with the naked eye.

  The occurrence mechanism of wrinkles is estimated as follows. In the conventional construction method, when the base material 105 is set in the molding hole, the enlarged diameter portion of the base material 105 and the lower mold are in contact with each other, and when the base material 105 is pushed with a punch, As shown in FIG. 19 (a), when the lower diameter G1 side of the enlarged diameter portion flows quickly and the enlarged diameter portion reaches the side wall of the lower mold, as shown in FIG. 19 (b), the enlarged diameter portion. "Make M" part occurs. If the molding proceeds in this state, “offset wrinkles” will occur.

  Since the forming surface is bent into the forged product, the side wrinkles are caused in the flange portion, resulting in deterioration of sealing performance, insufficient tightening strength, and generation of cracks. For this reason, it was treated as a defective product, which deteriorated the production yield.

  The present invention has been proposed in view of the above, a molded product manufacturing method capable of reducing defective products in appearance inspection and improving production yield, and a forging die used when forging the molded product An object is to provide a molded product and a forging production system.

  1) In order to achieve the above object, the first invention provides a molded article comprising at least a cylindrical or columnar central portion and an enlarged diameter portion that is continuous from the central portion and has a larger diameter than the central portion in plan view. In the method of manufacturing a molded product manufactured from a molded material, when the molded material is set in a molding hole surrounded by an upper mold and a lower mold, the molded material becomes a central portion after molding. The center part contacts the lower mold, and a predetermined gap is formed in the extrusion direction between the enlarged mold part and the lower mold, which becomes the enlarged diameter part after molding. The method includes a step of manufacturing a molded product by extruding a base material.

  2) The second invention is characterized in that, in addition to the configuration of the invention described in the above item 1), the predetermined gap is 2 mm or more and 6 mm or less.

  3) In the third aspect of the invention, in addition to the configuration of the invention described in the above item 1) or 2), the above-mentioned shaped material has a curved surface at the corner portion between the enlarged diameter portion and the central portion. The radius of the curved surface is substantially the same as the predetermined gap.

  4) In the fourth aspect of the invention, in addition to the configuration of the invention described in any one of items 1) to 3), the base material may be any of casting, forging, machining, and extrusion. Or a pre-process comprising a combination thereof, or a combination thereof.

  5) In the fifth aspect of the invention, in addition to the configuration of the invention described in any one of items 1) to 4), an oil-based lubricant that is a mixture of graphite and mineral oil is previously added to the peripheral wall of the molding hole. It is characterized by applying.

  6) In the sixth aspect of the invention, in addition to the configuration of the invention described in any one of items 1) to 5), the temperature of the lower mold is set to 100 to 350 ° C. The temperature of the base material is maintained at 300 to 550 ° C., respectively.

  7) In the seventh invention, in addition to the structure of the invention described in any one of 1) to 6) above, the material of the above-mentioned shaped material is 10.0 to 11.5% by mass of Si, Fe 0.5% or less, Cu 2.0-3.0%, Mn 0.10%, Mg 0.2-0.5%, Cr 0.10% Zn is 0.10% by mass or less, Ti is 0.10% by mass or less, and the balance is Al.

  8) In the eighth aspect of the invention, in addition to the configuration of the invention described in any one of items 1) to 7), the base material is molded after being subjected to bondage treatment (phosphate film treatment). It is set in the hole.

  9) In the ninth aspect of the invention, in addition to the configuration of the invention described in any one of items 1) to 8) above, the central part of the molded product is formed in a plurality of stages, and the lower mold is formed in the center. In the depth direction of the molding hole that molds the front tip portion, which is the step at the tip in the direction of extrusion, the back pressure applying die is movable up and down, and the back pressure applying die forms the front tip portion. Waiting for the front tip surface of the front tip portion to be pushed out at a predetermined distance below the start position where formation of the front tip portion is started in the depth direction of the forming hole, and the front tip surface reaches After that, the front tip surface is pressed from below, and the surface is formed while applying back pressure having a predetermined initial value.

  10) In the tenth aspect of the invention, in addition to the configuration of the invention described in the above item 9), the back pressure applying mold may be a gas cushion, a hydraulic cushion, a hydraulic cushion, a spring cushion, or a combination thereof. The back pressure applying means presses the front end face from below to apply back pressure.

11) In the eleventh aspect of the invention, in addition to the configuration of the invention described in the above item 10), the back pressure applying means has an initial value of 35 to 35 when the front tip surface contacts the back pressure applying mold. grant back pressure of 55N / mm ² to the front tip surface, then gradually increasing the back pressure with the extrusion, to impart the back pressure of 45~65N / mm ² in the front distal end face as the final value at the extrusion completion, that It is a feature.

  12) The twelfth invention is characterized in that, in addition to the configuration of the invention described in the above item 11), the load at the time of completion of extrusion of the shaped material by the upper mold is 2400-3500 kN. Yes.

  13) The thirteenth invention is a pre-process forging die for producing a shaped material by forging from an original shaped material as a pre-process for producing a molded product, and a cylindrical or columnar central portion from the shaped material. And a post-process forging die that forges a molded product that has at least a diameter-increased portion that is continuous from the central portion and has a larger diameter than the central portion in plan view. The die for process forging and the die for post-process forging are a counter pin that receives the central part that becomes the central part of the molded product after molding in the extrusion direction, and the extrusion direction that becomes the enlarged part of the molded product after molding. There is a lower die corresponding to the enlarged diameter part received in the front, and the upper surface of the counter pin of the forging die for the previous process corresponds to the enlarged diameter part by a predetermined gap from the upper surface of the counter pin of the forging die for the subsequent process. Below the upper surface of the lower mold Are set to location, it is characterized in that.

  14) In the fourteenth aspect of the invention, in addition to the configuration of the invention described in the above item 13), the pre-process forging die has the predetermined portion at a portion corresponding to a corner portion between the enlarged diameter portion and the central portion. A curved surface having substantially the same radius as the gap is provided.

  15) The fifteenth invention is characterized in that it is a molded product manufactured by the method for manufacturing a molded product according to any one of items 1) to 12).

  16) The sixteenth invention is characterized in that, in addition to the configuration of the invention described in the above item 15), the forging line of the cross section at the enlarged diameter portion is along the outline.

  17) The seventeenth invention is a forging production system including the forging machine having the forging die described in the above item 13).

  In this invention, when the base material is set in a molding hole surrounded by the upper die and the lower die, the central portion of the raw material is brought into contact with the lower die and the diameter-enlarged portion A predetermined gap is formed in the extrusion direction between the upper mold and the lower mold, and the molded product is manufactured by extruding the molded product with the upper mold from the set state. First, it will be pushed forward first, and its forward extrusion site will be shaped first (starts). As a result, at the initial stage of molding, the raw material is pushed forward to be molded, and then the material flows by being diverted to the lateral direction and the front of the enlarged diameter portion. For this reason, it can suppress that a lower part flows quickly in the enlarged diameter part projected in the horizontal direction, and each horizontal flow in the lower part side and upper part side of an enlarged diameter part becomes almost the same speed. Therefore, the occurrence of wrinkles can be suppressed, defective products can be reduced, and the production yield can be improved.

  Further, since the predetermined gap formed in the extrusion direction between the enlarged diameter portion and the lower mold is set to 2 mm or more and 6 mm or less, the gap is too narrow, and the material flow in the lateral direction on the lower side of the enlarged diameter portion is reduced. Appropriately, it becomes too fast or, conversely, the gap is too large and the material flow in the lateral direction on the upper side of the enlarged diameter portion becomes faster, and the material spreads laterally from the gap and the dent (folding) occurs. Can be prevented.

  In addition, since the radius R of the curved surface provided at the corner portion between the enlarged diameter portion and the central portion of the shaped member is substantially the same as the predetermined gap formed in the extrusion direction, The material that shunts in the direction will flow smoothly and in a well-balanced manner, so that the lateral flow on the lower and upper sides of the enlarged diameter part will also flow at approximately the same speed. Occurrence can be suppressed, defective products can be reduced, and production yield can be improved.

  Moreover, since the oil-based lubricant which is a mixture of graphite and mineral oil is applied to the peripheral wall of the molding hole in advance, the lubrication effect can be enhanced and the mold temperature can be prevented from being lowered.

  Furthermore, since the temperature of the lower mold is kept at 100 to 350 ° C., and the temperature of the forming material when set in the forming hole is kept at 300 to 550 ° C., a sufficient plastic flow and a stable lubricant application state can be obtained. Can be maintained.

  Further, in this invention, the back pressure applying mold is in the depth direction of the forming hole for forming the front tip portion which is the step at the tip in the push-out direction of the central portion, and the start position where the formation of the front tip portion is started When waiting for the extruded shape material at a lower distance than the predetermined distance, and when the front end surface of the front end portion extruded by the extrusion of the shape material by the upper die comes into contact with the back pressure applying die From this, the back pressure applying mold presses the front tip surface from below to form the surface while applying a back pressure of a predetermined initial value or more. There is no difference between the horn-like portion (acute angle portion) at the tip portion and the central portion, and the tip portion becomes uniform, and the tensile force generated between the portions is reduced.

  In addition, the shape is complicated, for example, when the material flows in a three-stage state at the time of molding, the thickness is reduced and the part having the most difficult shape is molded last. At the time of the last molding, the temperature of the shaped material will decrease, but the back pressure application mold presses the front tip surface from below to apply a back pressure of a predetermined initial value or more. Appropriate heat storage is performed at the tip portion, so that the temperature of the shaped material can be properly maintained. Therefore, the plastic fluidity of the shaped material can be maintained.

  Further, according to the present invention, the back pressure applying die is pushed out by a predetermined distance in the depth direction of the forming hole for forming the front tip portion and starting from the formation of the front tip portion. Since the shape material is waiting, the lubricant can be applied in advance to the peripheral wall of the molding hole at the front end portion, and in this state, the extrusion of the shape material can be waited. Friction between the forming hole and the shape material of the front end portion is relieved and the flow of the shape material is improved. As a result, the flow of the shape material at the front end portion is changed between the acute angle portion and the central portion. The difference is eliminated and uniformized, and the tensile force generated between the parts is reduced.

  And, as mentioned above, the flow of the shaped material can be made uniform at the front end portion, and the plastic fluidity of the shaped material can be maintained, so that it can be produced in a single forging process, thereby producing In addition, molding defects such as cracks, cracks, and sagging can be reliably prevented, and defective appearance inspection products can be reduced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  1 and 2 are views showing an example of a molded product produced by the method of the present invention. As shown in FIGS. 1 and 2, a molded product 9 manufactured by the method of the present invention has a cylindrical or columnar central portion 92 and an enlarged diameter that is continuous from the central portion 92 and has a larger diameter than the central portion 92 in plan view. Part (flange part) 91 is provided at least. In the example shown in the figure, the central portion 92 is further composed of two stages, an upper stage 92a and a lower stage 92b.

  FIG. 3, FIG. 4 and FIG. 5 are explanatory views of the molded product manufacturing method of the present invention. FIG. 3 schematically shows a case where the molded product of FIG. 1 is manufactured. FIG. 4 schematically shows a case where the molded product of FIG. 2 is manufactured. FIG. 5 is an example of an improved version of FIG. 4 in which a gap L5 for absorbing the lateral overhang of the central portion of the shaped material is provided. Here, a step H is provided at the bottom to prevent further material displacement. ing.

  In these drawings, the base material 90 is a material that becomes a molded product 9 after molding, and includes a central portion 920 that becomes a central portion after molding and a diameter-expanded portion 910 that becomes a diameter-expanded portion after molding. The molded product manufacturing method according to the present invention is configured such that when the raw material 90 is set in the forming hole 4 surrounded by the upper die (not shown) and the lower die 3, The central portion 920 is in contact with the lower mold 3 so that a predetermined gap L1 is formed between the enlarged diameter portion 910 and the lower mold 3 in the extrusion direction. The molded product 9 is manufactured by extruding the shape material. Next, the flow of the raw material when it is manufactured from the set state of FIG. 3 by the molded product manufacturing method of the present invention will be described using FIG.

  FIG. 6 is a diagram schematically illustrating the flow of the raw material when a molded product is manufactured by the method of the present invention. FIG. 6A shows the timing when the punch (upper mold) 2 descends to the position of the base material 90 set in the molding hole 4 and molding starts. FIG. 6B shows the timing at which the base material 90 is first pushed forward by the punch 2. 6 (c) and 6 (d) show a state in which the base material 90 is pushed and diverted by the punch 2 in the forward and lateral directions.

  In this way, at the initial stage of molding, the base material 90 is pushed forward by a predetermined gap, and then the raw material is flowed by being diverted in the lateral direction (in the enlarged diameter direction) and the front. It is preferable to balance such that when the flow is divided, the amount of forward flow is large and the flow speed is increased. In the present invention, since the predetermined gap L1 is provided between the base material 90 and the lower mold 3, it is possible to prevent the lower portion 910a side of the expanded diameter portion 910 protruding in the lateral direction from rapidly flowing, and molding It is possible to prevent wrinkles from occurring on the rearward enlarged diameter portion 91.

  In the conventional method in which the predetermined gap L1 is not provided between the base material 90 and the lower mold 3, as shown in FIG. 19, when the base material is pushed by a punch, the lower G1 side of the enlarged diameter portion is fast. When the fluid flows and the enlarged diameter portion reaches the side wall of the lower mold, a turn-up portion M is generated in the enlarged diameter portion.

  In the method of the present invention, in order to provide the predetermined gap L1 between the base material 90 and the lower mold 3, the base material 90 is pressed forward at the initial stage of molding, and then the lateral direction of the diameter-enlarged portion 910 The material flows by diverting forward. For this reason, as described above, it is possible to suppress the lower portion 910a side from rapidly flowing in the diameter-expanded portion 910 that protrudes in the lateral direction, and each lateral flow on the lower portion 910a side and the upper portion 910b side of the diameter-increased portion 910 can be prevented. It becomes almost the same speed. Therefore, the occurrence of wrinkles can be suppressed, defective products can be reduced, and the production yield can be improved.

  Next, it demonstrates more concretely using FIGS.

  FIG. 7 is an overall view showing one structural example of a forging die used in the practice of the present invention, FIG. 8 is an external view of a molded product manufactured with this forging die, and FIGS. 9 and 10 are forgings according to the present invention. FIGS. 9A, 9B, 9C, and 9C sequentially show the manufacturing process when manufacturing a molded product having the shape shown in FIG. 8 using a metal mold. FIGS. ) (E) (f) shows the latter half.

  In these drawings, the forging die 1 of the present invention is forged in a direction substantially perpendicular to the main molding direction (forward in the extruding direction) while extruding the base material 90 in the upper die lowering direction. 8 is a mold for manufacturing a molded product 9 as shown in FIG. The molded product 9 has a three-stage structure, and includes a flange portion (expanded diameter portion) 91 and a cylindrical central portion 92. The central portion 92 includes a front end portion 93 in a horn shape.

  In the forging die 1, a base material 90 is set in a molding hole 4 surrounded by a pair of an upper die 2 and a lower die 3, and the upper die 2 is lowered to load the base material 90. Then, the molded product 9 is manufactured by extruding and molding the raw material 90 forward in the downward direction. By the movement of the upper mold 2 in the descending direction, the base material 90 is pushed forward and formed into a central portion 92 including a front tip portion 93 and a flange that is formed by expanding in the lateral direction. Part 91. Further, the forging die 1 is configured as a main part of the forging device, and the vertical movement of the upper die 2 and the vertical movement of a knockout pin 37 to be described later are performed by a drive mechanism of the forging device. .

  The upper mold 2 mainly molds the upper part of the product shape, and the lower mold 3 molds the lower part of the product shape mainly.

  The lower mold 3 includes a nested die 31 that mainly molds the side surface of the product shape, a convex die (counter pin) 32 that mainly forms an inner peripheral surface, and a die 33 that surrounds the nested die 31. The nesting mold 31 is formed in a hollow shape at the center, and the convex mold 32 is erected in the hollow portion. Then, the inner peripheral wall surface of the insert mold 31 and the outer peripheral wall surface of the convex mold 32 constitute the molding hole 4, and the lowering of the upper mold 2 reaches the bottom dead center, forging is completed, and the state shown in FIG. 7 is obtained. At this point, the molded product 9 (the base material 90) is formed with a flange portion 91, a cylindrical central portion 92, and a front tip portion 93.

  A back pressure pin (back pressure applying mold) 34 is disposed below (front) the molding hole 4 a for molding the front end portion 93 of the molding hole 4 between the nesting die 31 and the convex die 32. A gas cushion 35, a stopper 36, and a knockout pin 37 are provided further below the back pressure pin 34. The back pressure pin 34, the gas cushion 35, and the stopper 36 constitute back pressure applying means.

  Further, from a lubricant spraying device not shown here, the lubricant is sprayed and applied to the peripheral wall surface of the molding hole 4. As this lubricant, an oil-based lubricant such as mineral oil is used, and a mixture of graphite and mineral oil is preferable because the lubricating effect is enhanced. In addition, since the mold temperature is lowered in the case of water-based lubricants, oil-based lubricants are preferable from this point.

  A heater 8 that heats the lower mold 3 to control the temperature is disposed on the outer peripheral upper edge of the die 33. The heating capacity of the heater 8 is preferably 250 to 400 ° C. A simple and small heater can be used. For example, a power supply of 200 V, an output of 2 kw, and a MAX 450 ° C. specification can be mentioned.

  In order to obtain a sufficient plastic flow, the temperature of the lower mold 3 is preferably maintained at 100 to 350 ° C. (preferably 120 to 250 ° C.) by the heater 8 described above. If it is less than this, the molding becomes unstable, and if it exceeds this, the lubricant application state becomes unstable. It is preferable that the temperature of the raw material 90 when being set in the molding hole 4 is maintained at 300 to 550 ° C.

  It is preferable to use alloy tool steel or cemented carbide as the material of the inner peripheral wall surface in contact with the base material 90 of the nesting die 31, and cemented carbide is particularly preferable from the viewpoint of wear resistance against frictional resistance. Further, it is preferable to perform a CVD process such as TiC as a coating process on the surfaces of the nesting mold 31 and the convex mold 32 corresponding to the front end portion 93. This is because the seizure resistance is improved. The surface roughness of the portion is Ry = 0.5 μm or less, preferably 0.1 to 0.4 μm. This is because the seizure resistance is improved and the plastic flow is more fully controlled.

  As the material of the base material 90, a metal material that can be plastically processed by forging can be used. For example, aluminum, iron, magnesium, and alloys based on these can be given.

  If it is an aluminum alloy, an Al-Mg-Si alloy can be used, and a JIS6061 alloy, an A390 alloy, etc. can be used. For example, Si is 10.0 to 11.5 mass%, Fe is 0.5 or less mass%, Cu is 2.0 to 3.0 mass%, Mn is 0.10 or less mass%, and Mg is 0.2 to 0 mass%. 0.5% by mass, Cr is 0.10% by mass or less, Zn is 0.10% by mass or less, Ti is 0.10% by mass or less, and the balance is Al.

  The manufacturing method of the shaped member 90 used in the present invention may be any of continuous casting, extrusion, rolling and the like. In the case of aluminum or an aluminum alloy, a continuously cast round bar is preferable because it is inexpensive. In an aluminum alloy, a round bar material (for example, SHOTIC material (registered trademark) manufactured by Showa Denko KK) continuously cast by a gas pressure hot top casting method has excellent internal soundness and fine crystal grains. In addition, since there is no crystal grain anisotropy due to plastic working, the resistance effect of the frictional resistance portion can be obtained stably, which is preferable.

  The process of forming the flange portion by forging in the direction perpendicular to the main molding direction while extruding the base material 90 in the upper mold lowering direction will be described.

  (A) It is preferable to apply the oil lubricant only to the molds 2 and 3 without applying the lubricant to the base material 90 side at the time of molding. A water-soluble lubricant can be used for the lubricant treatment of the mold when the shape and dimensions can be stably produced by molding in a desired range. This is because it is easy to obtain the effect of suppressing the material flow in the surface layer portion and reducing the difference in the flow rate in the lateral direction.

  (B) The shape of the raw material 90 and the insert mold (lower mold) 31 are designed so that a predetermined gap L1 (4 mm in this case) is secured (FIG. 9A). .

  (C) The upper surface 31a of the lower mold 31 forming the flange portion 91 and the upper surface 32a of the convex mold 32 are in the same position (FIG. 9A). Of the thrown shape material 90, the thickness of the shape material 90 located above the convex mold 32 is 4 mm thicker than the thickness of the flange portion 910. That is, when the base material 90 is introduced and the hole bottom surface 920h of the central portion 920 contacts the upper surface 32a of the convex mold 32, the main molding is performed between the lower surface 910m of the flange portion 910 and the upper surface 31a of the lower mold 31. A gap L1 of 4 mm can be ensured in the direction (FIG. 9A). Details of the case where such a shaped member 90 is formed by forging will be described later.

  (D) As a result, in the initial stage of molding, the shaped material 90 is pushed forward by 4 mm to be shaped, and thereafter, as shown in FIG. become. That is, the raw material 90 is first pushed forward before projecting sideways, and then the material flows by being diverted in the lateral direction and forward of the flange portion 910. For this reason, it can suppress that the lower part 910a side flows quickly in the flange part 910, and each horizontal flow in the lower part 910a side and the upper part 910b side of the flange part 910 becomes substantially the same speed. Therefore, the occurrence of wrinkles can be suppressed, defective products can be reduced, and the production yield can be improved.

  (E) If the predetermined gap L1 is too large, for example, exceeds 6 mm, the metal spreads laterally from the gap, and the flange portion 910 may be driven (folded).

  FIG. 12 is an explanatory view of the occurrence of driving when the predetermined gap L1 is set to 6 mm. (A) shows a state in which a 4 mm shape material is pushed in with an upper mold, and (b) and (c) are further in order. It shows the state pushed in with a mold. As shown in FIG. 12, when the gap is 6 mm, when the base material 90 is pushed by 4 mm with the upper mold 2, a gap of 2 mm still remains (FIG. 12 (a)). Of the speed of the material flowing in the direction, the speed of the material on the lower part 910a side is increased, and the portion J protrudes in the lateral direction to cause imbalance (FIG. 12B), and driving W is generated (FIG. 12). (C)).

  (F) The difference between the outer diameter of the shaped member 90 and the hole diameter of the molding hole 4 is preferably 0.3 mm to 0.7 mm.

  The molded product obtained as described above becomes a molded product through a heat treatment process and a machining process as necessary.

  Next, using FIG. 9 and FIG. 10, the operation of the back pressure applying means at the time of forming the front end portion will be described as a preferred form.

  By applying the back pressure, the metal flowing forward can be pressed, and the lateral flow is easy to flow horizontally, which is preferable because wrinkles are less likely to occur.

  Further, when the shape having the front tip portion 93 is formed into a horn shape, it is preferable because the occurrence of cracks can be suppressed on the side surface of the front tip portion 93 and defects in appearance can be reduced.

  First, in FIG. 9A, the raw material 90 cut to a predetermined size is inserted into the molding hole 4. At this time, the upper end surface of the back pressure pin 34 is in the depth direction of the forming hole 4a for forming the front tip portion 93 and is below the start position M where the formation of the front tip portion 93 is started by a predetermined distance D. At the position, the extruded shape member 90 is waiting. The predetermined distance D is set to 25 to 70% of the total length in the depth direction of the front end portion 93. For example, when the total length in the depth direction is 10.5 mm, the predetermined distance D can be set to 2.6 to 7.3 mm.

  Next, since the upper mold 2 is lowered and presses the base material 90, plastic flow starts. When the plastic flow further proceeds, the shaped member 90 flows into the forming hole 4a as shown in FIG. 9B, and then reaches the upper end surface of the back pressure pin 34 as shown in FIG. 9C. To do.

  Since the back pressure from the gas cushion 35 is preliminarily applied to the back pressure pin 34 as an initial value, the back pressure pin 34 remains stopped until the upper mold 2 is further lowered and exceeds the initial value. Does not change.

  The gas cushion 35 applies a back pressure to the front tip surface 93b of the front tip portion 93 via the gas cushion piston 35a and the back pressure pin 34. When the load exceeds the back pressure, the gas cushion 35 is retracted, and the back pressure pin 34 is pushed down in accordance with the contraction. As shown in FIG. 10 (d), the base material 90 is placed in the molding hole 4a. It will fill up. Thereafter, as shown in FIG. 10 (e), the back pressure pin 34 comes into contact with the stopper 36 to stop and the molding is completed. Thereafter, the upper mold 2 is raised, and the molded product 9 remaining in the molding hole 4 is pushed up by the knockout pin 37 and taken out from the molding hole 4 as shown in FIG.

  FIG. 13 is a diagram showing the back pressure by the gas cushion. In addition, (a)-(e) of a horizontal axis is equivalent to each time of FIG. 9 (a)-FIG.10 (e), and the vertical axis | shaft has shown back pressure.

  The back pressure generated by the gas cushion 35 acts on the front end surface 93 b via the back pressure pin 34 and is applied to the base material 90. As shown in FIG. 13, the back pressure P is “0” at the time of (a) and (b) until the shaped member 90 reaches the upper end surface of the back pressure pin 34, and has reached (c). At the time, the initial value P1 of the gas cushion 35 is reached. The back pressure P gradually increases until the time point (e) at which the lower end surface of the back pressure pin 34 abuts against the stopper 36, and reaches the final value P2 at the time point (e). That is, from (c) to (e), the molding is performed in a state in which the back pressure P is applied to the base material 90 via the front tip surface 93b. Thereafter, since the upper mold 2 is raised, the back pressure P is lowered to “0”.

Here, the initial value P1 of the back pressure P is, for example, 35 to 55 N / mm ² when the load (main load) is 2400 to 3500 KN when the upper die 2 reaches the bottom dead center and the extrusion is completed. After that, the stroke of the gas cushion 35 is changed to a final value P2, which is preferably 45 to 65 N / mm ² . If the pressure exceeds this range with respect to the change in stroke, the plastic flow of the shaped member 90 will not be successful, and cracking, seizure, and poor filling may occur. If the final value P2 of the back pressure P is within 100 to 130% of the initial value P1, molding can be performed stably, which is preferable. The back pressure P may be obtained by one set of gas cushion 35 and back pressure pin 34, or may be obtained by a plurality of sets.

  As described above, in this embodiment, the back pressure pin 34 is pushed out by a predetermined distance D below the start position M in the depth direction of the forming hole 4a and starting to form the front tip portion 93. From the time when the front end surface 93b comes into contact with the back pressure pin 34 by pushing out the original shape member 90 by the upper mold 2, the front end surface 93b is viewed from below. Since the surface 93b is formed while pressing and applying a back pressure greater than or equal to the predetermined initial value P1, the flow of the shaped member 90 at the front tip portion 93 is between the corner portion (acute angle portion) 93a and the central portion. The difference disappears and becomes uniform, and the tensile force generated between the parts is reduced.

  In addition, when the shape is complicated and the material flows in a three-stage state at the time of molding like the molded product 9, the portion 93 having the thinnest shape and the most difficult shape is molded last. As a result, the temperature of the base material 90 is lowered at the time of the last molding, but in the forging die 1 of the present invention, the front tip surface 93b is pressed from below by the back pressure pin 34. The back pressure pin 34 is stopped until the back pressure exceeding the predetermined initial value P1 is applied and the load from above exceeds the predetermined initial value P1, and the base material 90 stays at the front end portion 93. Thus, it can be considered that moderate heat storage is performed on the front end portion 93 and the temperature of the shaped member 90 can be properly maintained, and therefore the plastic fluidity of the shaped member 90 can be maintained.

  Further, the back pressure pin 34 waits for the extruded shape member 90 in the depth direction of the forming hole 4a and below the start position M where the formation of the front end portion 93 is started by a predetermined distance D. Since it did in this way, a lubrication agent can be previously apply | coated not only to the upper side of the surrounding wall of the shaping | molding hole 4, but to the surrounding wall of the shaping | molding hole 4a of the lower side, and it waits for extrusion of the raw material 90 in that state It becomes like this. Accordingly, the region S from the start position M to the predetermined distance D is filled with the lubricant that has flowed through the peripheral wall as the raw material 90 is pushed out and becomes a lubricant reservoir, and the region S contains the lubricant. Fully supplied. Therefore, the friction between the forming hole 4a and the shape member 90 of the front end portion 93 is greatly relieved to improve the flow of the shape member 90. As a result, the flow of the shape member 90 at the front end portion 93 is improved. Also from this point, it can be considered that there is no difference between the corner (acute angle part) 93a and the central part, and the tensile force generated between the parts becomes uniform.

  And as mentioned above, since the flow of the shaped material 90 can be made uniform at the front end portion 93 and the plastic fluidity of the shaped material 90 can be maintained, the shape of the molded product 9 is complicated. Can also be manufactured in a single forging process, thereby improving productivity. Also, molding defects such as cracks, cracks, and sagging can be reliably prevented.

  Further, in the molded product 9 manufactured using the forging die 1 described above, the metal flow is continuous from the center portion 92 to the front tip portion 93, so the mechanical strength of the front tip portion 93 is good. It will be something. In addition, it is possible to suppress the occurrence of molding defects at the front end portion 93 and, in particular, since it has a sufficiently acute angle shape, post-processing steps such as machining can be omitted.

  Although the gas cushion 35 is used for the back pressure applying means, the type is not particularly limited as long as it has a predetermined pressure (initial value) with zero stroke displacement. Besides the gas cushion, a hydraulic cushion, a hydraulic cushion, and a spring cushion can be used.

  Next, an example in which forging (1F process) is used as a pre-process for obtaining the raw material 90 to be introduced from the raw material will be described with reference to FIG. As the forging device, the same device as that shown in FIG. 8 can be used. The forging process for obtaining the molded product 9 from the raw material 90 is referred to herein as a 2F process and is distinguished from the 1F process.

  FIG. 14 is an explanatory diagram in the case of forming a raw material from a raw material by forging. As shown in this figure, when forming the base material 90 from the raw base material 900, the upper surface 32a of the convex mold (counter pin) 32 is not a horizontal position but a predetermined position with respect to the upper surface 31a of the lower mold 31. The gap L1 is lowered by 4 mm, and the raw material shape 900 is placed on the convex mold 32 for setting.

  In addition, in this 1F process, when a shape and a dimension can be stably produced within a desired range, a water-soluble lubricant can be used for the lubricant treatment of the mold. It is preferable that the raw material is subjected to a bond lubrication treatment. It is preferable to apply oil-based lubrication to the mold because stable molding can be obtained.

  (A) When the forming hole of the lower mold in the 1F step is φ42.4 mm, the diameter of the raw material (raw material) to be input is prepared to φ41.8 mm. Conventionally, since a material having a diameter of φ48 mm (flange-shaped inscribed circle diameter) is used, the material cannot enter the forming hole. However, in this embodiment, as shown in FIG. Molding is started with it completely inserted.

  (B) The molding start position (position where the material hits the mold and plastic flow starts) is assumed to be a position having a diameter of 42.4 mm and a depth of 4 mm in the mold hole (FIG. 14).

(C) To achieve this, for example, in the mold in the 1F process, the bottom of the center of the molding hole is lowered by 4 mm from the outer flange. That is, as described above, the upper surface 32a of the convex mold (counter pin) 32 is lowered from the upper surface 31a of the lower mold 31 by a predetermined gap L1 of 4 mm.
(D) As a result of the above (a) and (b), the plastic flow (metal flow) of the material by forging in the 1F process is only forward pushing first (preferentially filling the metal hole with φ42.4 mm) After that, the material (metal) is pushed out in the lateral direction, and the metal overhang in the horizontal direction (spread to the flange) flows almost horizontally with respect to the main forming direction (vertical axis) The state is almost parallel on the lower surface of the upper surface.

  As described above, a 1F molded product in which the metal overhang in the lateral direction is in a substantially uniform state can be obtained. By using this as the base material 90, the occurrence of “offset wrinkles” can be further suppressed.

  (E) Since the shape member 90 obtained in this way has a central portion 920 having a thickness of 4 mm, a predetermined gap L1 can be obtained by using this as the shape material 90.

  (F) In addition, when the raw material (material) 900 is introduced in the 1F process, the material diameter is reduced and dropped into the center of the mold, so the bottom corner of the material is directly in the horizontal direction. The corner is dropped into the molding hole until it does not overhang. As a result, the corners do not appear on the side surfaces and cause “wrinkles”.

  At this time, as a result, the raw material is projected in the lateral direction from the middle of the side surface in the longitudinal direction. Preferably, the curved surface (radius R) is imparted to the portion S of the lower mold so that the metal is formed. The flow is stable. This is shown in FIG.

  Further, since the curved surface S here corresponds to the corner portion of the base material 90, the radius R to be applied is matched with the distance of a predetermined gap L1 provided between the lower mold and the input base material 90. This is preferable because it is possible to suppress the occurrence of the driving W as described with reference to FIG. The radius R of the curved surface S is preferably over 2 mm. Furthermore, it is more preferable that R = 3 mm to 6 mm.

  (G) The shape material 90 manufactured in the 1F process in this way has a diameter of 48 mm × length of 26.6 mm (upsetting rate of 50%) in the conventional method, but in the present invention, the diameter is 41.8 mm × length. Since the length is 35.1 mm (upsetting 60%), the upsetting ratio of the base material 90 to the raw base material 900 is increased. As a result, the effect that the material particle size becomes fine and the mechanical strength becomes high is also obtained. Here, the upsetting rate is (total material length-1F molded product thickness) / total material length × 100.

  Moreover, in the conventional 1F process, since the material of the flange shape size is used from the beginning, the following problems are likely to occur. Most of the molding process is forward molding, and in the molded product, drawing occurs on the surface on the punch (upper mold) side opposite to the molding direction, resulting in poor appearance. In addition, when molding using a flange-shaped material, the pressurization area increases from the initial stage, and because the metal flows only in the forward direction, it is difficult for the metal on the outer periphery of the flange to flow and the molding load increases. Mold life is shortened.

  On the other hand, in this embodiment, as shown in FIG. 14, the occurrence of these problems can be suppressed by assuming that the raw material shape material 900 is placed inside the mold hole used in the previous process. Is preferable.

  (H) Since the cross-sectional shape is multi-stage and the raw material having the shape to flow simultaneously in the forward and lateral directions, work hardening occurs vigorously and cracking occurs in cold forging, so warm and hot forging ( A material temperature of 300 to 550 ° C. and a mold temperature of 110 to 350 ° C. are preferable.

  (I) On the other hand, when a material with a diameter of 41.8 mm is used, if the depth of the central portion is less than 3 mm, the material is misaligned because the depth distance is shallow, and the flow does not become separate in the forward and lateral directions. Since wrinkles are generated, a sufficient effect cannot be obtained.

  Although the case where forging is used as a pre-process for forming the raw material 90 has been described, other forming methods include the following forming processes.

  (A) Casting molding: A molding 90 is formed by molding a molding that can obtain a predetermined distance L1 in the gap as a casting.

  (B) Casting and forging: In the case of complex shapes, a casting having a rough shape is input as a material for the 1F process, and a forging material is formed by forging so that the gap is a predetermined distance L1. , And let it be a raw material 90.

  (C) Molding and machining by molding: In the case of a complicated shape, a casting having a rough shape is molded by machining so that the gap is a predetermined distance.

  (D) Machining: A material 90 is formed by machining so that the gap is a predetermined distance L1.

  (E) Machining molding and forging molding: A material formed by machining into a rough shape is introduced as a material for the 1F process, and a forging material is formed by forging so that the gap becomes a predetermined distance L1. Is a raw material 90.

  (F) Forging forming and machining forming: In the case of a complex shape, a rough shape 90 is formed by forging a rough shape and then forming it so that the gap becomes a predetermined distance L1 by machining.

  (G) Extrusion molding: A molding material 90 obtained by molding a molding material that can obtain a predetermined distance L1 in the gap by an extrusion method.

  (H) Extrusion molding to machine molding: In the case of a complicated shape, an extruded product having a rough shape is molded by machining so that the gap is a predetermined distance L1. To do.

  Next, the forging production system of the present invention will be described.

  FIG. 16 is a diagram schematically showing an example of the forging production system of the present invention. This forging production system includes a continuous casting apparatus 601, a homogenizing apparatus 602, a straightening apparatus 603, a peeling apparatus 604, a material cutting apparatus 605, a bonder processing apparatus 607, a material heating apparatus 608, and a forging apparatus (forging machine) 609. Is done. The forging device 609 includes the forging die described above.

  When there is one forging device, the molds of the 1F process / 2F process are changed. Alternatively, a dedicated forging device is provided for each of the 1F process and the 2F process.

  Moreover, you may provide the solution heating apparatus 610, the quenching apparatus 611, and the aging treatment apparatus 612 in the back | latter stage of the forging apparatus 609 as needed. In addition, a molten metal treatment device (not shown) for improving the purity of the molten metal may be provided in the front stage of the continuous casting apparatus 601.

  Further, if necessary, a device for preheating the raw material and further performing a lubrication treatment can be provided in front of the 2F forging device.

  And an integrated production line can be comprised by providing an automatic conveyance apparatus for conveyance between each apparatus. Furthermore, an integrated automatic production system including a raw material supply device (not shown), a raw material conveyance device (not shown), and a molded product discharge device (not shown) is a more preferable system.

  Among the above devices, the material cutting device 605 is for cutting the material into a predetermined length. The material supply device holds a certain amount of forging material in the hopper and supplies the material to the next process. The material conveying device is for conveying a forging material to a mold. The forging device 609 is for forging a forging material. The molded product carry-out device is for discharging the molded product from the mold by a knockout pin mechanism and transporting it to the next process. The material heating device 608 is for heating the material to a recrystallization temperature or higher to improve forging processability. The aging treatment device 612 is for heat treatment for continuously solution-treating and aging treatment of the taken-out molded product.

  In addition, although the case where the pre-forming of the material was set to 1F was described as an example, when the other forming method described above is used as the pre-process, the process before 2F is a casting apparatus, a machining apparatus, and a combination thereof. It will be replaced.

  Hereinafter, although a specific example is shown and the effect of this invention is clarified, this invention is not limited to this.

  A molded product 9 having the shape shown in FIGS. 1 and 2 was manufactured using the forging die according to the present invention. The main load was 3000 kN at the bottom dead center. Table 1 shows conditions such as the gap distance L1, the mold lubricant, the mold temperature, the temperature of the forging material, and the presence or absence of back pressure. The lubricant for forging material was not applied. The raw material was prepared as follows.

  The material is Si: 10.30, Fe: 0.20, Cu: 2.40, Ti: 0.01, Mn: 0.01, Mg: 0.35, Cr: 0.01, Zn: 0.01 ( An aluminum alloy containing (unit: mass%), which was obtained by cutting a continuously cast casting rod, was used as a forging material for 1F, and was manufactured using the mold shown in FIG.

  Table 1 also shows the results of evaluating the molding state by the results of appearance observation after molding.

  As can be seen from Table 1, in Examples 1 to 10, wrinkles were not generated near the flange portion in any case. Furthermore, in the cases of Examples 1 to 4, 6, 7, and 8 in which a molded product was manufactured by providing a gap L1 of 4 mm between the flange portion of the material shape and the upper surface of the lower mold below it, in any case There was no wrinkle on the flange and no crease (folding) occurred on the bottom of the flange.

It is a figure which shows an example of the molded article manufactured with this invention method. It is a figure which shows an example of the molded article manufactured with this invention method. It is explanatory drawing of the molded article manufacturing method of this invention. It is explanatory drawing of the molded article manufacturing method of this invention. It is explanatory drawing of the molded article manufacturing method of this invention. It is a figure which shows typically the flow of the raw material when manufacturing a molded article with the method of this invention in order. It is a general view which shows one structural example of the metal mold | die for forging used for implementation of this invention. It is an external view of the molded product manufactured with the die for forging of FIG. It is a figure which shows in order the first half of the manufacturing process at the time of manufacturing the molded article which has a shape shown in FIG. 8 using the metal mold | die for forging of this invention. It is a figure which shows in order the second half of the manufacturing process at the time of manufacturing the molded article which has a shape shown in FIG. 8 using the metal mold | die for forging of this invention. It is explanatory drawing of the material flow in this invention method. It is explanatory drawing of the driving | operation which generate | occur | produces when the predetermined clearance L1 is 6 mm. It is a figure which shows the back pressure by a gas cushion. It is explanatory drawing in the case of shape | molding a raw material from a raw material. It is explanatory drawing of the metal flow in the lower metal mold | die which provided the curved surface S. FIG. It is a figure which shows the outline of an example of the forge production system of this invention. It is explanatory drawing of the conventional forging process. It is a figure which shows an example of the forged product manufactured at the conventional forging process. It is explanatory drawing in the case of producing "bending" in the enlarged diameter part of a molded product when it manufactures by the conventional method.

Explanation of symbols

1 Forging die 2 Upper die (punch)
3 Lower mold 4, 4a Molding hole 8 Heater 9 Molded product 31 Nested mold (lower mold)
31a Upper surface of lower mold 32 Convex mold 32a Upper surface of convex mold 33 Die 34 Back pressure pin 35 Gas cushion 35a Gas cushion piston 36 Stopper 37 Knockout pin 90 Substrate material 91 Expanded portion (flange portion)
92 Central portion 92a Upper portion of central portion 92b Lower portion of central portion 93 Front tip portion 93b Front tip surface 601 Continuous casting device 602 Homogeneous processing device 603 Straightening device 604 Peeling device 605 Material cutting device 607 Bonde processing device 608 Material heating processing device 608 Material Heating device 609 Forging device 610 Solution heating device 611 Quenching device 612 Aging treatment device 900 Raw material 910 Flange part 910 Expanded part 910a Expanded part lower part 910b Expanded part upper part 920 Central part 920h Central part hole Bottom

Claims (17)

In a molded product manufacturing method for manufacturing a molded product comprising at least a cylindrical or columnar central portion and a diameter-enlarged portion that is continuous from the central portion and has a larger diameter than the central portion in plan view,
When the above-mentioned shape material is set in a molding hole surrounded by the upper die and the lower die, the central portion of the shape material that becomes the central part after molding comes into contact with the lower die, and after molding A predetermined gap is formed in the extrusion direction between the enlarged diameter portion to be the enlarged diameter portion and the lower mold,
A process for producing a molded product by extruding a shape material with an upper mold from the set state is included.
A method for producing a molded product characterized by the above.   The method for producing a molded product according to claim 1, wherein the predetermined gap is 2 mm or more and 6 mm or less.   The method of manufacturing a molded product according to claim 1 or 2, wherein the base material has a curved surface at a corner portion between the enlarged diameter portion and the central portion, and a radius of the curved surface is substantially the same as the predetermined gap. .   The molding according to any one of claims 1 to 3, wherein the base material is preformed in a pre-process comprising any one of casting molding, forging molding, machining molding, extrusion molding, or a combination thereof. Product manufacturing method.   The method for producing a molded product according to any one of claims 1 to 4, wherein an oil-based lubricant that is a mixture of graphite and mineral oil is applied in advance to the peripheral wall of the molding hole.   The molding according to any one of claims 1 to 5, wherein the temperature of the lower mold is maintained at 100 to 350 ° C, and the temperature of the base material when set in the molding hole is maintained at 300 to 550 ° C. Product manufacturing method.   The material of the above-mentioned shaped material is 10.0 to 11.5% by mass of Si, 0.5% by mass or less of Fe, 2.0 to 3.0% by mass of Cu, 0.10% by mass or less of Mn, Mg is 0.2 to 0.5 mass%, Cr is 0.10 mass% or less, Zn is 0.10 mass% or less, Ti is 0.10 mass% or less, and the balance is Al. Item 7. The method for manufacturing a molded article according to any one of Items 1 to 6.   The molded product manufacturing method according to any one of claims 1 to 7, wherein the base material is set in a molding hole after being subjected to bondage treatment (phosphate film treatment). The central part of the molded product is formed in a plurality of stages,
The lower mold is provided with a back pressure applying mold that can move up and down in the depth direction of the molding hole that molds the front tip portion that is the step at the tip of the center in the extrusion direction,
The back pressure applying mold is a front tip portion that is extruded in a depth direction of a molding hole for molding the front tip portion and a predetermined distance below a start position where the formation of the front tip portion is started. Waiting for the front tip surface, and after the front tip surface arrives, press the front tip surface from below, forming the surface while applying back pressure having a predetermined initial value,
The method for manufacturing a molded article according to any one of claims 1 to 8.   The back pressure applying mold presses the front end face from below by a back pressure applying means comprising a gas cushion, a hydraulic cushion, a hydraulic cushion, a spring cushion, or a combination thereof, and applies back pressure. A method for producing a molded product according to 1. The back pressure applying means applies a back pressure of 35 to 55 N / mm ² as an initial value to the front tip surface when the front tip surface comes into contact with the back pressure applying die, and then gradually increases the back pressure with extrusion. The molded product manufacturing method according to claim 10, wherein a back pressure of 45 to 65 N / mm ² is applied to the front end face as a final value at the time of completion of extrusion.   The method for producing a molded product according to claim 11, wherein a load at the time of completion of extrusion of the shaped material by the upper mold is set to 2400 to 3500 kN. As a pre-process for manufacturing a molded product, a pre-process forging die for manufacturing a base material by forging from an original base material,
A post-process forging die for forging and manufacturing a molded product comprising at least a cylindrical or columnar central portion and a diameter-enlarged portion having a diameter larger than that of the central portion in plan view, from the above-mentioned shaped material; In the forging mold consisting of
The pre-process forging die and the post-process forging die include a counter pin that receives the central portion that becomes the central portion of the molded product after molding in the extrusion direction and a diameter-expanded portion that becomes the enlarged diameter portion of the molded product after molding. Each has a lower mold corresponding to the enlarged diameter portion to be received in front of the extrusion direction,
The upper surface of the counter pin of the pre-process forging die is set to be positioned below the upper surface of the lower die corresponding to the enlarged diameter portion by a predetermined gap from the upper surface of the counter pin of the post-process forging die. ing,
A forging die characterized by that.   14. The forging die according to claim 13, wherein the pre-process forging die is provided with a curved surface having substantially the same radius as the predetermined gap at a portion corresponding to the corner portion between the enlarged diameter portion and the central portion. Type.   A molded article produced by the method for producing a molded article according to any one of claims 1 to 12.   The molded product according to claim 15, wherein the forged flow line of the cross section at the enlarged diameter portion is along the outline.   A forging production system comprising a forging machine having the forging die according to claim 13.

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