Swaging method and swaging apparatus

Abstract

An upsetting method capable of reducing a molding pressure is provided. The upsetting method uses a receiving die 11 and a guide 20 having an insertion hole 23 for inserting and holding a diameter expansion scheduled portion 2 of the raw material 1 in a buckling prevented state and in an axially slidable manner, the insertion hole being penetrated from the basal end to the tip end of the guide 20 . The method includes a step of receiving the diameter expansion scheduled portion 2 of the raw material 1 by the receiving portion 13 of the receiving die 11 and disposing the diameter expansion scheduled portion 2 of the raw material 1 in the insertion hole 23 of the guide 20 , and a step of expanding a diameter of the diameter expansion scheduled portion 2 of the raw material 1 exposed between the tip end face 21 a of the guide 20 and the receiving portion 13 of the receiving die 11 by moving the guide 20 in a direction opposite to a pressurizing direction of the diameter expansion scheduled portion 2 of the raw material 1 while pressurizing the diameter expansion scheduled portion 2 of the raw material 1 with a pressurizing means 30 in an axial direction, after the step of disposing the diameter expansion scheduled portion 2 of the raw material 1 . At the diameter expanding step, the diameter expansion is performed in a state in which a portion 2 a of the diameter expansion scheduled portion 2 of the raw material 1 corresponding to a tip end portion 21 of the guide 20 is locally heated by the heating means 40.

1 . An upsetting method using a receiving die having a receiving portion and a guide having an insertion hole for inserting and holding a diameter expansion scheduled portion of a raw material in a buckling prevented state and in an axially slidable manner and a raw material outlet portion which is one end opening of the insertion hole provided at a tip end face of the guide,
 the upsetting method comprising:   a step of receiving the diameter expansion scheduled portion of the raw material by the receiving portion of the receiving die and disposing the diameter expansion scheduled portion of the raw material in the insertion hole of the guide; and   a step of expanding a diameter of the diameter expansion scheduled portion of the raw material exposed between the tip end face of the guide and the receiving portion of the receiving die by moving the guide in a direction opposite to a pressurizing direction of the diameter expansion scheduled portion of the raw material while pressurizing the diameter expansion scheduled portion of the raw material with a pressurizing means in an axial direction, after the step of disposing the diameter expansion scheduled portion of the raw material,   characterized in that, at the diameter expansion step, the diameter expansion is performed in a state in which a portion of the diameter expansion scheduled portion of the raw material corresponding to a tip end portion of the guide is locally heated by the heating means.   
   
   
       2 . The upsetting method as recited in  claim 1 ,
 wherein the heating means is an induction heating means having an induction heating coil, and   wherein, at the diameter expansion step, the diameter expansion is performed in a state in which the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of the guide is inductively heated with the induction heating coil arranged at the tip end portion of the guide.   
   
   
       3 . The upsetting method as recited in  claim 1 ,
 wherein the heating means is an induction heating means having an induction heating coil, and   wherein, at the diameter expansion step, the diameter expansion is performed in a state in which the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of the guide is heated by inductively heating the tip end portion of the guide with the induction heating coil arranged at the tip end portion of the guide.   
   
   
       4 . The upsetting method as recited in  claim 2  or  3 , wherein the tip end portion of the guide having the induction heating coil is connected to a main body of the guide via a heat insulating layer. 
   
   
       5 . The upsetting method as recited in  claim 1 , wherein, at the diameter expansion step, the diameter expansion is performed in a state in which the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of the guide is heated into a half molten state. 
   
   
       6 . The upsetting method as recited in  claim 1 , wherein, at the diameter expansion step, the diameter expansion is performed in a state in which an inner surface of a portion of the insertion hole located at a basal end side of the guide relative to the tip end portion of the guide is cooled with a first cooling means. 
   
   
       7 . The upsetting method as recited in  claim 1 ,
 wherein a molding portion having a cavity for molding the diameter expansion scheduled portion of the raw material into a designed shape is extended from the receiving portion of the receiving die,   wherein, at the step of disposing the diameter expansion scheduled portion of the raw material, the diameter expansion scheduled portion of the raw material is received by the receiving portion of the receiving die, the diameter expansion scheduled portion of the raw material is disposed in the insertion hole of the guide, and the tip end portion of the guide is disposed in the cavity of the receiving die, and   wherein, at the diameter expansion step, the diameter expansion scheduled portion of the raw material exposed between the tip end face of the guide and the receiving portion of the receiving die is expanded in diameter in the cavity of the receiving die.   
   
   
       8 . The upsetting method as recited in  claim 7 , wherein, at the diameter expansion step, the diameter expansion is performed in a state in which a molding surface of the cavity of the receiving die is cooled with a second cooling means. 
   
   
       9 . An upset forged article obtained by the upsetting method as recited in  claim 1 . 
   
   
       10 . An upsetting method using a receiving die having receiving portions formed at both axial end portions and a holding hole communicating with both the receiving portions for holding a non-diameter-expansion scheduled portion of a raw material and two guides each having an insertion hole for inserting and holding a diameter expansion scheduled portion of the raw material located at an axial end side in a buckling prevented manner and in an axially slidable manner with respect to the non-diameter-expansion scheduled portion of the raw material and each having a raw material outlet portion constituted by one end opening of the insertion hole provided at the tip end face,
 the upsetting method comprising:   a step of receiving each diameter expansion scheduled portion of the raw material by a corresponding receiving portion of the receiving die by disposing the non-diameter-expansion scheduled portion of the raw material in the holding hole of the receiving die and disposing both the diameter expansion scheduled portions of the raw material in the insertion holes of the guide respectively; and   a step of simultaneously expanding both the diameter expansion scheduled portions of the raw material exposed between the tip end face of each guide and the corresponding receiving portions of the receiving die by moving each guide in a direction opposite to a pressurizing direction of the corresponding diameter expansion scheduled portion of the raw material while pressurizing both the diameter expansion scheduled portions of the raw material with the pressuring means in the axial direction respectively,   characterized in that, at the diameter expansion step, the diameter expansion is performed in a state in which a portion of each diameter expansion scheduled portion of the raw material corresponding to a tip end portion of the guide is locally heated with a heating means.   
   
   
       11 . The upsetting method as recited in  claim 10 ,
 wherein the heating means is an induction heating means having an induction heating coil, and   wherein, at the diameter expansion step, the diameter expansion is performed in a state in which the portion of each diameter expansion scheduled portion of the raw material corresponding to the tip end portion of each guide is inductively heated with the induction heating coil disposed at the tip end portion of each guide.   
   
   
       12 . The upsetting method as recited in  claim 10 ,
 wherein the heating means is an induction heating means having an induction heating coil, and   wherein, at the diameter expansion step, the diameter expansion is performed in a state in which the portion of each diameter expansion scheduled portion of the raw material corresponding to the tip end portion of each guide is heated by inductively heating the tip end portion of each guide with the induction heating coil disposed at the tip end portion of each guide.   
   
   
       13 . The upsetting method as recited in  claim 11  or  12 , wherein the tip end portion of each guide having the induction heating coil is connected to a main body of the guide via a heat insulating layer. 
   
   
       14 . The upsetting method as recited in  claim 10 , wherein, at the diameter expansion step, the diameter expansion is performed in a state in which the portion of each diameter expansion scheduled portion of the raw material corresponding to the tip end portion of each guide is heated into a half molten state. 
   
   
       15 . The upsetting method as recited in  claim 10 , wherein, at the diameter expansion step, the diameter expansion is performed in a state in which an inner surface of a portion of the insertion hole located at a basal end side of each guide relative to the tip end portion of the guide is cooled with a first cooling means. 
   
   
       16 . The upsetting method as recited in  claim 10 ,
 wherein a molding portion having a cavity for molding the diameter expansion scheduled portion of the raw material into a designed shape is extended from each receiving portion of the receiving die,   wherein, at the step of disposing the diameter expansion scheduled portion of the raw material, each diameter expansion scheduled portion of the raw material is received by the receiving portion of the receiving die by disposing the non-diameter-expansion scheduled portion of the raw material in the holding hole of the receiving die, both the diameter expansion scheduled portions of the raw material are disposed in the insertion hole of the guide respectively, and the tip end portions of the guides are disposed in the cavities of the receiving die respectively, and   wherein, at the diameter expansion step, both the diameter expansion scheduled portions of the raw material exposed between the tip end face of each guide and each receiving portion of the receiving die are simultaneously expanded in diameter in the corresponding cavity of the receiving die respectively.   
   
   
       17 . The upsetting method as recited in  claim 16 , wherein, at the diameter expansion step, the diameter expansion is performed in a state in which a molding surface of each cavity of the receiving die is cooled with a second cooling means. 
   
   
       18 . An upset forged article obtained by the upsetting method as recited in  claim 10 . 
   
   
       19 . An upsetting apparatus, comprising:
 a receiving die having a receiving portion for receiving a diameter expansion scheduled portion of a raw material;   a guide having an insertion hole for inserting and holding the diameter expansion scheduled portion of the raw material in a buckling prevented state and in an axially slidable manner and a raw material outlet portion constituted by one end opening of the insertion hole formed at a tip end face;   pressurizing means for pressurizing the diameter expansion scheduled portion of the raw material disposed in the insertion hole of the guide in an axial direction; and   guide driving means for moving the guide in a direction opposite to a pressurizing direction of the diameter expansion scheduled portion of the raw material,   wherein it is configured such that the diameter expansion scheduled portion of the raw material exposed between the tip end face of the guide and the receiving portion of the receiving die is expanded in diameter, and   characterized in that the upsetting apparatus further comprises a heating means for locally heating a portion of the diameter expansion scheduled portion of the raw material corresponding to a tip end portion of the guide.   
   
   
       20 . The upsetting apparatus as recited in  claim 19 ,
 wherein the heating means is an induction heating means having an induction heating coil, and   wherein it is configured to inductively heat the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of the guide by the induction heating coil disposed at the tip end portion of the guide.   
   
   
       21 . The upsetting apparatus as recited in  claim 19 ,
 wherein the heating means is an induction heating means having an induction heating coil, and   wherein it is configured to heat the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of the guide by inductively heating the tip end portion of the guide with the induction heating coil disposed at the tip end portion of the guide.   
   
   
       22 . The upsetting apparatus as recited in  claim 20  or  21 , wherein the tip end portion of the guide having the induction heating coil is connected to a main body of the guide via a heat insulating layer. 
   
   
       23 . The upsetting apparatus as recited in  claim 19 , wherein the heating means is capable of heating the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of the guide into a half molten state. 
   
   
       24 . The upsetting apparatus as recited in  claim 19 , further comprising a first cooling means for cooling an inner surface of a portion of the insertion hole located at a basal end side of the guide relative to the tip end portion of the guide. 
   
   
       25 . The upsetting apparatus as recited in  claim 19 ,
 wherein a molding portion having a cavity for molding the diameter expansion scheduled portion of the raw material into a designed shape is extended from the receiving portion of the receiving die, and   wherein it is configured to expand a diameter of the diameter expansion scheduled portion of the raw material exposed between the tip end face of the guide and the receiving portion of the receiving die within the cavity of the receiving die.   
   
   
       26 . The upsetting apparatus as recited in  claim 25 , further comprising a second cooling means for cooling a molding surface of the cavity of the receiving die. 
   
   
       27 . An upsetting apparatus, comprising:
 a receiving die having receiving portions formed at both axial end portions and a holding hole communicating with both the receiving portions for holding a non-diameter-expansion scheduled portion of a raw material;   two guides each having an insertion hole for inserting and holding a diameter expansion scheduled portion of the raw material located at an axial end side in a buckling prevented state and in an axially slidable manner with respect to the non-diameter-expansion scheduled portion of the raw material and each having a raw material outlet portion constituted by one end opening of the insertion hole formed at the tip end face;   two pressurizing means each for pressurizing the diameter expansion scheduled portion of the raw material disposed in the insertion hole of each guide in the axial direction;   two guide driving means each for moving each guide in a direction opposite to a pressurizing direction of the corresponding diameter expansion scheduled portion of the raw material,   wherein it is configured to simultaneously expand diameters of both the diameter expansion scheduled portions of the raw material exposed between the tip end face of each guide and the corresponding receiving portion of the receiving die,   characterized in that the upsetting apparatus further comprises two heating means for locally heating a portion of each diameter expansion scheduled portion of the raw material corresponding to a tip end portion of the guide.   
   
   
       28 . The upsetting apparatus as recited in  claim 27 ,
 wherein each heating means is an induction heating means having an induction heating coil, and   wherein it is configured to inductively heat the portion of each diameter expansion scheduled portion of the raw material corresponding to the tip end portion of each guide by the induction heating coil disposed at the tip end portion of each guide.   
   
   
       29 . The upsetting apparatus as recited in  claim 27 ,
 wherein each heating means is an induction heating means having an induction heating coil, and   wherein it is configured to heat the portion of each diameter expansion scheduled portion of the raw material corresponding to the tip end portion of each guide by inductively heating the tip end portion of each guide with the induction heating coil disposed at the tip end portion of each guide.   
   
   
       30 . The upsetting apparatus as recited in  claim 28  or  29 , wherein the tip end portion of each guide having the induction heating coil is connected to a main body of each guide via a heat insulating layer. 
   
   
       31 . The upsetting apparatus as recited in  claim 27 , wherein each heating means is capable of heating the portion of the diameter expansion scheduled portion of the raw material corresponding to the tip end portion of each guide into a half molten state. 
   
   
       32 . The upsetting apparatus as recited in  claim 27 , further comprising a first cooling means for cooling an inner surface of a portion of the insertion hole of each guide located at a basal end side of the guide relative to the tip end portion of the guide. 
   
   
       33 . The upsetting apparatus as recited in  claim 27 ,
 wherein a molding portion having a cavity for molding the diameter expansion scheduled portion of the raw material into a designed shape is extended from each receiving portion of the receiving die, and   wherein it is configured to simultaneously expand diameters of both the diameter expansion scheduled portions of the raw material exposed between the tip end face of each guide and each receiving portion of the receiving die within each cavity of the receiving die.   
   
   
       34 . The upsetting apparatus as recited in  claim 33 , further comprising a second cooling means for cooling a molding surface of each cavity of the receiving die.