JPS6239848Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a mandrel device for an extrusion press.

(Prior art) For example, in high-temperature lubricated extrusion of tubular products,
The applicant has proposed Japanese Patent Application Laid-Open No. 2003-120013 with the aim of improving product quality and facilitating post-processing by reliably and easily removing carbonized lubricant adhering to the inner surface of tubular products at the same time as the extrusion process. In Japanese Patent No. 57-91822, a high temperature lubricated extrusion method for tubular products has already been proposed.

The above method will be explained based on FIG. 10. A stem 2 and a mandrel 3 are connected to the main crosshead 1 in the above order in the extrusion direction.
The stem 2 presses the billet 7 into a container 6 through a press die 8 through a seal piston 4 and a pressure medium 5.
Pressure is applied to the side to extrude the tubular product 9 from between the tip of the mandrel 3 inserted into the billet 7 and the die 8.

Further, in the axial center of the main crosshead 1, stem 2, and mandrel 3, there is provided an axial direction for supplying a combustion improver or a fluid, which is a mixture of a combustion improver and water, into the product 9 from an external supply means 10. supply path 11,
12 and 13 are formed to penetrate in the axial direction.

Then, while extruding the product 9, fluid is released into the product 9 to completely burn the lubricant and pressure medium 5 extruded into the product 9 from between the tip of the mandrel 3 and the billet 7. In addition, adhesion of carbides of the lubricant and pressure medium 5 is prevented, thereby preventing deterioration of the quality of the product 9 and causes of deterioration such as corrosion.

(Problems to be Solved by the Invention) The present invention is intended to apply the technique for supplying a fluid into a product as described above to an extrusion press as described below.

That is, in the extrusion press to which the above application is applied, a press stem is provided protruding from the main crosshead in the extrusion direction, and a mandrel is connected to a mandrel holder via a mandrel socket within the main crosshead and the press stem. The body is provided such that its constituent members are arranged in the above order toward the distal end.

However, if the above-mentioned conventional technology is applied as is, the fluid supply path must be formed in the axial direction not only in the mandrel but also in the elongated mandrel holder like the mandrel, which makes it difficult to form the fluid supply path. The problem was that it became cumbersome, difficult, and expensive to form.

(Means for Solving the Problems) An object of the present invention is to provide a mandrel device for an extrusion press that can easily form a fluid supply path and can be formed at low cost.

In order to achieve this objective, the feature of the present invention is that the joint is formed in the radial direction on the distal side of the joint between the mandrel holder and the mandrel socket, and is connected to the axial supply path from the outside. A seal that is provided with a radial supply path for supplying fluid, and that prevents fluid from leaking to the outside at a location that sandwiches the radial supply path in the axial direction between the combined body and a cylindrical member externally fitted thereon. The point is that you have the means.

(Example) The following is a first example in which the present invention is applied to an indirect extrusion press.
The embodiment will be described with reference to FIGS. 1 and 2. Reference numeral 16 denotes a cylindrical main crosshead, which is movable back and forth on the press axis. Main crosshead 1
The distal end side of the device 1 has a larger diameter than the base side.
It is said to be 7.

Reference numeral 18 denotes a cylindrical press stem, which is concentrically attached to and detachable from the main crosshead 16 and protrudes in the extrusion direction, the base of which is attached to the equipment part 1
A stem backer 19 is inserted into the stem backer 7 and is fixed to the base end surface of the stem backer 19, which contacts the bottom surface of the equipment section 17. Further, a ring-shaped press plate 20 is integrally provided at the tip of the press stem 18.

A fixing device 21 is fitted onto the base of the press stem 18 and inserted into the equipment section 17 to detachably fix the press stem 18 and stem backer 19 to the main crosshead 16.

A cylindrical packing case 22 is removably fitted into the stem packer 19, and its inner surface is stepped, and the inner surface of its proximal end has a smaller diameter than the inner surfaces of other parts.

24 is a combination of mandrel devices with a circular cross section;
It is provided concentrically within the main crosshead 16 and press stem 18, and is movable back and forth on the press axis by a lock cylinder (not shown).
The combined body 24 is constructed by arranging an elongated cylindrical mandrel holder 25, a short cylindrical mandrel socket 26, and an elongated cylindrical mandrel 27 in the above order.

The mandrel socket 26 has a stepped cylindrical shape, and consists of a small diameter portion 28, an intermediate diameter portion 29, and a large diameter portion 30, each of which has a larger diameter toward the tip, which are successively arranged in the above order toward the tip. 28 is mandrel holder 2
It is removably inserted and screwed into the tip of 5.
Further, the large diameter portion 30 is externally screwed to the base end portion of the mandrel 27 in a detachable manner.

The mandrel 27 is of a chip mandrel type, and has a small diameter tip.

32 is a cylindrical die stem, press stem 18
A die 34 having a die hole 33 is integrally provided at the front end of the press.

A container 35 is provided with a hollow or solid billet 36 inside.

Figure 1 shows a solid billet 36 to a tubular product 37.
The mandrel 27 is inserted into the billet 36 while performing piercing action by the lock cylinder, the tip of the mandrel 27 is inserted into the die hole 33, and in this state, the combined body is extruded. 24 is fixed by a lock cylinder.

After that, the container 35 and the press stem 18
is moved in the extrusion direction, the billet 36 is pressurized between the press plate 20 and the die 34, and the billet 36
passes between the tip of the mandrel 27 and the die 34 and is extruded into the die stem 32 as a tubular product 37. 38 is the solid part of the product 37 at the initial stage of extrusion.

Therefore, in order to supply gas such as nitrogen gas into the product 37, the following configuration is adopted.

That is, an axial supply path 40 is formed in the axial center of the mandrel 27 to penetrate in the axial direction, and a socket 2 is formed in the axial center of the mandrel socket 26.
6. A blind hole-shaped axial supply path 41 is formed in the axial direction from the bottom surface of the inside on the distal end side to an axially midway part of the intermediate diameter portion 29 and communicates with the axial direction supply path 40.

Further, in the intermediate diameter portion 29 of the mandrel socket 26, a plurality of radial supply passages 42 extending from the outer peripheral surface to the axial supply passage 41 are arranged at equal intervals in the circumferential direction.

Furthermore, radial supply passages 43, 44, and 45 extending from the outer circumferential surface of the main crosshead 16 to the inner circumferential surface of the packing case 22 are formed through the tip of the main crosshead 16, the stem backer 19, and the packing case 22.

A nitrogen gas supply source 46 is connected to the outer end opening of the radial supply path 43 via a main supply pipe 47, and the main supply pipe 47 has an electromagnetic switching valve 48 that opens and closes the supply path.
is interposed.

Further, an auxiliary supply pipe 50 is extended from the main supply pipe 47 on the radial supply path 43 side with respect to the electromagnetic switching valve 48, and its tip opening is opened to the atmosphere. The auxiliary supply pipe 50 is provided with an electromagnetic switching valve 51 that opens and closes the supply path, and a check valve 52 that allows only the flow of air from the tip opening of the auxiliary supply pipe 50 to the main supply pipe 47 side. It is placed facing toward the tip side.

During extrusion, the electromagnetic switching valve 51 of the auxiliary supply pipe 50 is closed, the electromagnetic switching valve 48 of the main supply pipe 47 is opened, and nitrogen gas is supplied to the nitrogen gas supply source 4.
From 6, the main supply pipe 47, the electromagnetic switching valve 48, the radial supply paths 43, 44, 45, the inside of the packing case 22, the gap between the press stem 18 and the mandrel holder 25, the intermediate diameter between the press stem 18 and the mandrel socket 26 Gap between parts 29, radial supply path 4
2. Supply the inside of the tubular product 37 via the axial supply channels 41 and 40.

In this way, by creating a nitrogen gas atmosphere inside the product 37, oxidation, etc. inside the product 37 is prevented, and the quality of the inner surface of the product 37 is made good, and the inside of the product 37 becomes a vacuum. To prevent deformation caused by

Also, if necessary, when nitrogen gas is supplied, the electromagnetic switching valve 51 of the auxiliary supply pipe 50 is opened to allow the flow of nitrogen gas inside the main supply pipe 47 to direct atmospheric air from the auxiliary supply pipe 50 to the main supply pipe. Deformation caused by vacuuming the inside of the product 37 by sucking it into the product 37 to adjust the nitrogen gas concentration, or by sucking air into the product 37 without supplying any nitrogen gas during extrusion. prevent.

Therefore, the large diameter portion 30 of the mandrel socket 26
The outer circumferential surface is provided with a sealing material 54 that comes into sliding contact with the inner circumferential surface of the press stem 18, and the inner circumferential surface of the proximal end of the packing case 22 is provided with a mandrel holder 2.
5. A sealing material 55 that comes into sliding contact with the outer circumferential surface is provided,
A sealing means is provided between the press stem 18, the packing case 22, and the combined body 24 at a location across the radial supply path 42 in the axial direction.
The gas supplied to the product 37 is prevented from leaking through the gap between the press stem 18, the packing case 22, and the combined body 24.

Furthermore, sealing materials 56 are provided on both the inner and outer circumferential surfaces of the stem packer 19 at locations across the radial supply path 44 in the axial direction, which contact the packing case 22 and the inner circumferential surface of the equipment section 17 of the main crosshead 16, respectively.
59 are provided, and the radial supply passages 43, 44, 4
Leakage of the supply gas from the connection point 5 is prevented.

FIG. 3 shows a second embodiment of the present invention, in which a press stem 18 and a press plate 20 are separate bodies, and a connecting cylinder portion 61 is provided rearwardly projecting from the press plate 20. An intermediate cylindrical body 62 is disposed concentrically inside the press stem 18, and the distal end of the intermediate cylindrical body 62 is removably externally fitted and screwed to the connecting cylindrical part 61 via a seal tape (not shown). A fastening nut 63 is removably screwed onto the base end of the intermediate cylindrical body 62 that protrudes rearward beyond the press stem 18, and the press stem 18 is held between the press plate 20 and the fastening nut 63, and the press stem 18, The intermediate cylindrical body 62 and the press plate 20 are integrated. The mandrel socket 26 is composed of a small diameter part 28 and a large diameter part 30, and a sealing material 54 provided in the large diameter part 30 is in sliding contact with the inner peripheral surface of the intermediate cylinder 62.

Further, the mandrel 27 has a blind hole-shaped axial supply passage 40 formed from its tip, and an axial supply passage 40 formed from the outer peripheral surface at the base end of the mandrel 27.
A radial supply path 42 is formed in the radial direction leading to zero.

A blind hole-shaped radial supply passage 65 is formed in the fastening nut 63 in the radial direction from the outer peripheral surface, and the main supply pipe 47 is provided with a connecting pipe 66, which connects the main crosshead 16 and the connecting pipe 66. The stem backer 19 is inserted in the radial direction and is removably screwed into the radial supply path 65 via a sealing tape (not shown). In addition, communication passages 67 and 68 are formed in the base end portion of the fastening nut 63 and the intermediate cylinder body 62 in a substantially axial direction, and the radial supply passage 65 and the intermediate cylinder body are connected via these communication passages 67 and 68. 62 and a gap between the intermediate portions of both axial directions of the press stem 18 are communicated with each other. Further, a radial supply passage 69 in the radial direction is formed penetratingly on the distal end side of the intermediate cylinder 62 , and the intermediate cylinder 6 is supplied through the radial supply passage 69 .
2 and the press stem 18, and the intermediate cylindrical body 6.
2 and the gap between the mandrels 27 are communicated with each other.

Therefore, nitrogen gas is supplied from the nitrogen gas supply source 46 to the main supply pipe 47, the electromagnetic switching valve 48, the connecting pipe 66,
radial supply path 65, communication paths 67, 68, gap between press stem 18 and intermediate cylinder 62, radial supply path 69, gap between intermediate cylinder 62 and mandrel 27,
It is supplied into the product 37 via the radial supply path 42 and the axial supply path 40.

Further, leakage of the supply gas to the outside through the gap between the combined body 24 and the mandrel 27 is prevented by the sealing tape between the connecting cylinder portion 61 and the intermediate cylinder 62 and the sealing material 54.

Furthermore, in order to suitably prevent leakage of the supply gas to the outside, a sealing material 71 that slides on the inner circumferential surface of the fastening nut 63 and the outer circumferential surface of the mandrel holder 25 is provided on the base end surface of the press stem 18 and on the distal end surface of the fastening nut 63. A sealing material 72 is in contact with the inner circumferential surface of the tip end of the press stem 18, a sealing material 73 is in contact with the outer circumferential surface of the intermediate cylinder 62, and a sealing material 74 is in sliding contact with the mandrel 27 on the inner circumferential surface of the press plate 20. However, the sealing materials 71 to 74 may be omitted as appropriate.

In the first and second embodiments, depending on the relationship between the outer diameter of the mandrel 27 and the inner diameter of the axial supply path 40, when the billet 36 is pierced by the mandrel 27, the axial direction There is a risk that a portion of the billet 36 may enter the tip of the supply path 40 and become clogged.

Therefore, in each of the third to fifth embodiments shown below, when the billet 36 is pierced by the mandrel 27, the billet 36 is prevented from entering into the axial supply path 40 of the mandrel 27 as follows. There is.

That is, in the third embodiment shown in FIGS. 4 and 5, the tip of the axial supply path 40 of the mandrel 27 has a tapered portion 75 toward the tip.
It is said that

When the billet 36 is pierced by the mandrel 27 shown in FIG.
By setting the supply gas such as nitrogen gas to an ultra-high pressure to prevent the billet 36 from entering the supply path 40 as much as possible, and when extruding the product 37 shown in FIG. 36 is easily extracted by the supply gas by the action of the tapered portion 75.

Moreover, in the fourth embodiment shown in FIGS. 6 and 7,
The axial supply path 40 has the same diameter over its entire length in the axial direction, and a cap 76 for closing the supply path 40 is removably inserted at the tip of the supply path 40.

When the billet 36 is pierced by the mandrel 27 shown in FIG. 6, the cap 76 prevents the billet 36 from entering the axial supply path 40, and when the product 37 is extruded as shown in FIG.
The cap 76 is blown out with supply gas to supply gas to the inside of the product 37.

Furthermore, in the fifth embodiment shown in FIGS. 8 and 9,
A tapered portion 75 as in the third embodiment is formed at the tip of the axial supply passage 40, and the supply passage 4
The diameter of the part other than the tip of 0 is large. Then, the cap 76 removably closes the distal end of the supply path 40 and taperly connects it to the tapered portion 75.
The rod 77 that passes through is provided protruding rearward, and the rod 77
A double-acting cylinder 78 opens and closes the cap 76.
The cylinder 78 is operated by the supply gas supplied to the supply path 40, thereby simplifying handling compared to the fourth embodiment.

In other words, when the billet 36 is pierced by the mandrel 27 shown in FIG. ing. When extruding the product 37 shown in FIG. 9, gas is supplied to the cylinder 78, the cap 76 is opened forward through the rod 77, and the gas is sent into the product 37.

In the embodiment, a chipped mandrel was used as the mandrel, but a floating mandrel may also be used, and a straight mandrel can be used regardless of the chipped mandrel or the floating mandrel. Further, a hollow billet may be used as the billet, and an extruded product having a hole at the tip may be used as the hollow billet.

Furthermore, when using a low-temperature billet made of aluminum, etc., water is supplied into the product.
The inner surface of the product may also be heat treated.

In addition to indirect extrusion presses, the present invention can also be applied to direct extrusion presses, isostatic extrusion presses, etc. When applied to isostatic extrusion presses, oxygen gas is blown into the product to The extruded lubricant and pressure medium are completely combusted to prevent blackening due to adhesion of carbides on the inner surface of the product.

(Effects of the invention) As described in detail above, according to the invention, the connecting body is formed in the radial direction on the distal end side of the connecting part between the mandrel holder and the mandrel socket in the combined body, and is connected to the axial supply path from the outside. Seal means that includes a radial supply path for supplying fluid and prevents fluid from leaking to the outside at a location between the combined body and a cylindrical member externally fitted onto the radial supply path in the axial direction. Since the fluid supply path is not formed in the axial direction in the elongated mandrel holder,
The fluid supply path can be easily formed, the above formation can be performed at low cost, and the sealing means allows fluid to leak to the outside from the gap between the combined body and the cylindrical member externally fitted thereto. It can also be prevented. The present invention has the various advantages mentioned above and is of great practical benefit.

[Brief explanation of the drawing]

Figures 1 and 2 show the first embodiment of the present invention, Figure 1 is an overall sectional view during extrusion work also showing the gas supply system, and Figure 2 also shows the gas supply system. FIG. 3 is an enlarged cross-sectional view of the main parts before extrusion work, FIG. 3 is a cross-sectional view during extrusion work also showing the gas supply system in the second embodiment of the present invention, and FIGS. The cross-sectional views in FIGS. 6 and 7 showing different operating states in the third embodiment of the invention are the sectional views in FIGS. 8 and 9 showing different operating states in the fourth embodiment of the invention. Each figure is a sectional view showing different operating states in the fifth embodiment of the present invention, and the tenth embodiment is a sectional view showing different operating states.
The figure is a sectional view also showing a conventional combustion improver supply system. 16... Main crosshead, 18... Press stem, 24... Combined body, 25... Mandrel holder, 26... Mandrel socket, 27... Mandrel, 34... Die, 35... Container, 36
... Billet, 37 ... Product, 40, 41 ... Axial direction supply path, 42-45, 65, 69 ... Radial direction supply path, 46 ... Nitrogen gas supply source, 54-5
9, 71-74... Seal material, 62... Intermediate cylinder, 67, 68... Communication path.

Claims (1)

[Scope of utility model registration request] A press stem is provided protruding from the main crosshead in the extrusion direction, and a combined body consisting of a mandrel connected to a mandrel holder via a mandrel socket is placed inside the main crosshead and the press stem, with its constituent members facing toward the tip side. Prepare the billets in the container so that they are lined up in the above order, pressurize the billets in the container between the tip of the press stem and the die, and extrude the tubular product from between the tip of the mandrel inserted into the billet and the die.
In a mandrel equipped with an axial supply path that is formed in the axial direction and supplies fluid into the product, a radial direction is provided on the distal side of the joint between the mandrel holder and the mandrel socket in the combined body. A radial supply passage is formed to supply fluid from the outside to the axial supply passage, and the radial supply passage is located between the coupling body and the cylindrical member externally fitted thereon, at a location sandwiching the radial supply passage in the axial direction. A mandrel device for an extrusion press, characterized in that it is equipped with a sealing means for preventing leakage of fluid to the outside.