JPH0780091B2 - Hollow billet scalping method and scalping device for metal extrusion - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for scalping hollow billets for metal extrusion and a scalping device, and extrudes an extruded pipe material from a hollow billet regardless of indirect or direct form. It is used in the pretreatment process.

(Prior Art) When extruding an extruded material with a metal extrusion press, it is possible to sculpt the black skin, oxide film, etc. on the billet surface.
It is indispensable from the viewpoint of ensuring the quality of the extruded material, and therefore, in the pretreatment step of extrusion molding, the skin of the billet is sculpted by using the scalping device for exclusive use of scalping or the extrusion equipment with scalping device.

As this scalping device, there are technologies proposed by the applicant of the present application, such as Japanese Utility Model Laid-Open Nos. 58-184222, 57-112829 and 57-112828.

(Problems to be Solved by the Invention) In any of the techniques described in the above publications, the basic configuration is that the billet is pushed toward the scalping die and only the outer skin of the billet is sculpted, that is, the hollow billet, that is, Hollow billets did not consider scalping the inner epidermis.

Referring to FIG. 16, the outline of the pretreatment and extrusion molding of the hollow billet when the extrusion molding is performed by using the hollow billet, and in the case of the solid billet 1, whether the outer skin of the billet 2 is the bite 2 is used or not. After scalping using a scalping device, a hollow billet 4 is formed by using a bite 3 to form a hollow billet 4, which is heated by a heater 5 and the like and then charged into a container 6, a die stem 7, a mandrel 8, and a pressure stem. Extrusion molding is performed using an extrusion tool such as 9.

When the hollow billet 4 is used, the outer skin of the hollow billet 4 is scalped with the cutting tool 2 or the like, then drilled with the cutting tool 3, and then extrusion-molded in the same manner as in the previous step.

In any case, when the extruded pipe material is obtained by using the hollow billet 4, the outer peripheral skin of the hollow billet 4 can be sculpted, but the inner peripheral skin can be drilled only. Not only is it difficult to maintain the concentricity between the inner diameter and the outer diameter, but it also requires special equipment, is too costly and time consuming, and in turn prolongs the press cycle, which is also problematic in terms of productivity. .

SUMMARY OF THE INVENTION The main object of the present invention is to eliminate the above-mentioned problems by scalping the outer peripheral skin and the inner peripheral skin of the hollow billet in the same scalping process before extrusion molding.

(Means for Solving Problems) In order to achieve the above-mentioned object, the present invention takes the following means. That is, the feature of the scalping method of the present invention is that before the extrusion step, the outer peripheral surface and the inner peripheral surface of the heated metal extrusion hollow billet are respectively scalped in the billet longitudinal direction in the same set state. is there.

Further, the feature of the scalping device of the present invention is a device for scalping the billet longitudinal direction in the same set state with the outer peripheral skin and the inner peripheral skin of the heated metal extrusion hollow billet before the extrusion step. There is a cutting edge that sculpts the outer peripheral surface of the billet by relative movement in the billet longitudinal direction of the hollow billet, and a cutting edge that sculpts the inner peripheral surface of the billet by relative movement in the billet longitudinal direction of the hollow billet. There is a point.

(Operation) According to the present invention, the hollow billet for metal extrusion is heated, and the heated billet is set for scalping.

Then, in this set state, the cutting edge for outer peripheral skin and the billet are relatively moved in the billet longitudinal direction, and the outer peripheral skin of the billet is scalping. Then, in this same set state, the inner peripheral surface cutting edge and the billet are relatively moved in the billet longitudinal direction, and the inner peripheral surface of the billet is scalped.

The inner and outer skin scalping may be performed simultaneously or individually, but since the billets are set in the same state, the concentricity between the inner diameter and the outer diameter can be maintained.

(Examples) Hereinafter, several methods of the present invention will be described in detail while explaining an apparatus shown in the drawings.

In FIGS. 1 and 2, 20 is a bed, and this bed 20
A pair of platens 21 are erected facing each other on the upper side, and the pair of platens 21 are connected by a column 22.

Reference numeral 23 is a crosshead, which is linearly reciprocally movable between the platens 21 using the column 22 as a guide member, and a pressurizing stem 24 having a hollow structure is attached to the front surface at the center thereof, to the left in the figure.

Reference numeral 25 denotes a telescopic cylinder device for outer peripheral skin scalping.On the other hand, in the figure, cylinder tubes 26 attached to the left and right of the platen 21 on the right side and the tubes 26 are fitted in oil-tight manners and are slidable. And a head 28 of each piston 27 is connected to a cross head 23.

Reference numeral 29 denotes an expansion and contraction cylinder device for inner skin scalping, which is a cylinder tube 30 which is attached so as to extend rearward at the center of the crosshead 23, to the right in the figure, and an oiltight fit to the cylinder tube 30 so that it can slide. And a stepped (flange-shaped) pressure head 33 is attached to the piston 31 via a tie rod 32. The pressure head 33 is a pressure stem.
It is slidably inserted in 24.

The pressure head 33 may have a straight shape having no outer peripheral flange as shown in FIG. 3 and a curved concave portion formed on the end face thereof.

34 is a scalping die device, on the other hand, in the figure, a die 36 is attached to the rear side at the center of the platen 21 on the left side through a holder 35 and the like, and the die 36 is ring-shaped and has a cutting edge on the inner peripheral edge. In addition, the outer peripheral surface of the cutting edge has a tip warping surface, and further has a ring-shaped tip removing tool 38 which is operated by the cylinder 37.

In addition, 39 is a billet loader, 40 is a chip chute, 41
Shows a cylinder for die replacement or position change. 42
Is the roller table after scalping.

Referring to FIGS. 4 to 8, a scalping method using the scalping device shown in FIGS. 1 and 2 is shown in the order of steps.

That is, when the hollow billet 43 is heated and then loaded into the center of the apparatus by the billet loader 39, the cross head
23 is advanced through the cylinder device 25, and the billet 43 is sandwiched between the pressure stem 24 and the die 36 as shown in FIG.

When hydraulic pressure is applied to the cylinder device 29 in this state, the pressurizing head 33 is advanced to sculpt the inner skin of the hollow billet 43 in the billet length direction, and the tip 43A thereof is projected outward as shown in FIG. .

When scalping of the inner skin is completed, cylinder device 25
By applying hydraulic pressure to the crosshead 23, the pressurizing stem 24 is accompanied by the forward movement of the crosshead 23, and the outer peripheral surface of the billet 43 is sequentially scalped by the cutting edge of the die 36 in the billet length direction to form the tip 43B in a spiral shape. .

When the scalping of the outer peripheral skin is completed as shown in FIG. 7, the cylinder device 29 is reduced, and the cylinder device 25 is also reduced as shown in FIG.
43B is detached by the excluding tool 38 and sent out of the machine through the chute 40, and the billet 43 is immediately conveyed to the next step, for example, a press, on the table 42.

Referring to FIGS. 9 to 15, there is shown a scalping device used in the second embodiment of the present invention and a scalping process thereof.

In this example, 3 connected to the head 20 with tie rods 22
The individual platens 21 are arranged facing each other with a space, a hole is penetrated through the center of the central platen 21, and a scalping die device 34 is mounted on the left side of the platen 21.

The platen 21 on the side facing the die device 34 is provided with a cylinder device 25 for outer peripheral skin scalping at the center thereof, and a piston 27 thereof is provided with a crosshead 23 continuously, and the crosshead 23 is provided at the center thereof. The pressurizing stem 24 is provided, and in the pressurizing stem 24, the eject cylinder device 45 is attached with the chamber 44.

Further, a cross head 46 is arranged between the central platen 21 and the platen 21 on the right side, and the cross head 46 is a piston 48 in the billet backup cylinder device 47.
The inner peripheral skin scalping cylinder device 29 has a tube defined therein, and the piston 27 is fitted into the tube 26 so that the pressure head 33 is connected in series.

That is, in this example, a means for inner skin epidermal scalping is provided on the side opposite to the pressure stem 24 with respect to the scalping die device 34, and portions common to the above-described first example are designated by common reference numerals. It

The outer and inner skins of the hollow billet 43 heated by using the apparatus shown in FIGS. 9 and 10 are simultaneously scalped in the billet length direction.

That is, the billet 43 is loaded by the loader 39 onto the center between the pressure stem 24 and the die device 34 as shown in FIG.
The backup cylinder 47 and the inner skin cylinder device 29 are both in an extended state and their positions are fixed (hydraulic lock, etc.), and the pressing head 33 is attached to the die device 34.
When the pressurizing stem 24 is advanced toward the die device 34 by applying hydraulic pressure to the cylinder device 25 in a state where the rear surface is on the vertical plane, the outer peripheral skin is cut off at the cutting edge of the die 36 as shown in FIGS. 12 and 13. The pressurizing head 33 simultaneously sculpts the inner skin.

When the predetermined scalping is finished, the tip 43A of the inner skin is stored in the chamber 44 as shown in FIG. 14, so when the backup cylinder 47 is retracted, the billet
43 is taken out in a state of being supported by the rod 32, and then the billet loader 39 is advanced below the billet 43 to support the billet 43 as shown in FIG. On the other hand, on the side of the crosshead 23 that has once retracted, the tip ejector cylinder 45 is extended to move the tip 43A into the chamber 44.
Further, the tip 43B is ejected from the die 36 by the excluding tool 38 as the cylinder 37 advances.

The billet 43 thus scalping is carried into the next process via the loader 39.

(Effect of the Invention) According to the present invention, since the scalping of the inner and outer peripheral skins of the hollow billet is performed in the same set state of the billet, the concentricity between the inner diameter and the outer diameter of the billet can be kept good.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional plan view of a scalping device used in the present invention, FIG. 2 is a cross-sectional elevational view of the same, and FIG. 4 to 8 are elevation sectional views showing the order of the scalping process using the apparatus of FIGS. 1 and 2, and FIG. 9 is an elevation sectional view of another scalping apparatus used in the present invention, and FIG. The figure is a cross-sectional view showing another example of the pressure head part for the inner skin, and FIGS. 11 to 15 are elevation cross-sectional views showing the order of the scalping process using the apparatus shown in FIG. 9, FIG. FIG. 7 is a process explanatory view showing scalping and extrusion of a conventional example. 24 …… Pressure stem for outer skin scalping, 33 …… Pressure head for inner skin scalping, 34 …… Scalping die device, 43 …… Hollow billet.

Claims (2)

[Claims] 1. A hollow extrusion billet for metal extrusion, characterized in that, before the extrusion step, the outer peripheral skin and the inner peripheral skin of a heated metal extrusion hollow billet are respectively scalped in the billet longitudinal direction in the same set state. Scalping method. 2. An apparatus for scalping the outer peripheral surface and the inner peripheral surface of a heated hollow billet for metal extrusion in the same set state before the extrusion step, respectively, in the billet longitudinal direction. A metal extrusion characterized by comprising a cutting edge that sculpts the outer peripheral surface of the billet by relative movement in the direction, and a cutting edge that sculpts the inner peripheral surface of the billet by relative movement in the billet longitudinal direction of the hollow billet. Hollow billet scalping device.