JPS63100129A - Heat treatment device for hollow pipe - Google Patents

Abstract

PURPOSE:To make non-oxidizing heat treatment and uniform heat treatment by providing seals, joint jigs for jointing in a manner as to permit the transmission of rotating force, etc., and permitting the relative movement of a heat treatment jig while passing cooling fluid to the inside of a hollow pipe. CONSTITUTION:This heat treatment device for the hollow pipe is formed of a rotatable hollow lower adapter 1 and upper adapter 2, the joint jig 4 and the heat treatment jig 5 relatively movable along the hollow pipe 3. The heat treatment jig 5 has a heating means 6 for annularly heating said hollow pipe 3, a heated vessel 7, the sealing means 8 for sealing said vessel and the hollow pipe 3, a means 9 for supplying a non-oxidizing gas to the inside of the vessel 7 and a gas discharging means 10. While the cooling fluid is run in the hollow pipe 3, the hollow pipe 3 is uniformly heat-treated with the above-mentioned jig 5.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention heats the inner surface of a hollow tube from the outer surface while cooling it, and heat-treats the hollow tube while maintaining a constant temperature gradient in the wall thickness direction. Regarding equipment.

(Prior art) As a heat treatment method for hollow metal tubes, the inner surface of the hollow tube is cooled while high-frequency heating is applied to the outer surface.

A method is known in which heat treatment is performed by applying a constant temperature gradient in the thickness direction of a hollow tube. In this case 3, the hollow tube is usually kept stationary and the high frequency heating coil is moved relative to the hollow tube. However, in general, the distance between the high-frequency heating coil and the outer surface of the hollow tube is not uniform in the circumferential direction, and also fluctuates while the high-frequency heating coil is moving, making it impossible to perform highly accurate heat treatment in the circumferential direction of the hollow tube. There was a problem.

To solve this problem, a heat treatment device was developed in Japanese Patent Laid-Open No. 60-1748, in which a hollow tube was rotated and heated from its outer surface by a high-frequency heating coil.
It is disclosed in Publication No. 25.

[Problem that the invention seeks to solve]

However, in the method disclosed in the above-mentioned publication, the hollow tube is heated and heat-treated in air using a high-frequency heating coil, so oxidation occurs in the heated part, and heat treatment at high temperatures or heat treatment of metals that are easily oxidized is difficult. There was a problem that it could not be used.

To prevent this, it is possible to place the entire heat treatment equipment in a non-oxidizing atmosphere, but such a configuration requires large equipment to create a non-oxidizing atmosphere, which increases equipment costs and increases running costs. It also becomes more expensive. especially.

When performing heat treatment on a long hollow tube, a huge and huge amount of equipment is required.

The present invention has been made in view of such problems.

The purpose of the present invention is to provide a relatively small-sized heat treatment device capable of uniformly performing oxidation-free heat treatment over the entire circumference and length of a hollow tube.

(Means for Solving the Problems) The present invention, which has been made to achieve the above object, has a substantially perpendicular
1 [A hollow lower sachet and an upper sachet arranged so as to be able to rotate twice on a line, the lower end of the hollow tube to be heat treated is placed at the upper end of the lower sachet, and the upper end of the hollow tube is placed at the lower end of the upper sachet, respectively;
A pair of joint jigs that are connected in a sealing relationship and capable of transmitting rotational force, and a heat treatment jig that is relatively movable along a hollow tube installed between the lower and upper sachets,
The heat treatment jig includes a heating means for annularly heating the hollow tube, a cylindrical heating container surrounding a heated portion of the hollow tube by the heating means, and a heating container disposed at both ends of the heating container. a sealing means for sealing between the hollow tube, a non-oxidizing gas supply means for supplying non-oxidizing gas into the heating container on one side of the heating means, and a non-oxidizing gas supplying means from inside the heating container on the other side of the heating means. The gist of the present invention is a heat treatment apparatus for hollow tubes, which is characterized by having a gas discharge means for discharging gas.

[Effect]

In the heat treatment apparatus of the present invention having the above-mentioned configuration, the hollow tube is connected between the upper and lower sacrifices by a pair of joint jigs.
ii! It is possible to rotate the hollow tube while flowing the cooling fluid inside the hollow tube, and to rotate the heat treatment jig relative to it while rotating the hollow tube. By moving the hollow tube to the center, the hollow tube can be uniformly heat-treated. In addition, when the heat treatment jig moves while heating the hollow tube, the heated portion of the hollow tube is surrounded by the heating container and the sealing means at both ends, so that non-oxidizing gas can be supplied to that space. By.

The heated portion of the hollow tube is maintained in an oxidation-free atmosphere, preventing oxidation during heat treatment.

(Example) A preferred embodiment of the present invention shown in one drawing will be described below.

FIG. 1 is a partially sectional side view showing one embodiment of the present invention. In the figure, 1 is a hollow lower part, 2 is a hollow upper part, and 1FIL is vertical! It is rotatably arranged on i. A five-rotation drive device (not shown) is connected to either the lower thrower 1 or the upper thrower 2.

Reference numeral 3 denotes a hollow metal tube to be heat treated; 4, the lower end of the hollow tube 3 is connected to the upper end of the lower droplet 1, and the upper end of the hollow tube 3 is connected to the lower end of the upper droplet 2, in a watertight and rotational manner. A pair of joint jigs that can be connected together. Details of the joint jig 4 will be described later.

Reference numeral 5 denotes a heat treatment jig that is relatively movable along the hollow tube 3 installed between the lower sacrificial piece 1 and the upper sacrificial piece 2. This heat treatment jig 5 includes a cylindrical heating means 6 that annularly heats the hollow tube 3, and a cylindrical heating container 7 disposed surrounding the portion of the hollow tube 3 heated by the heating means 6. Sealing means 8 are arranged at both ends of the heating container 7 to seal between the heating container and the hollow tube, and non-oxidizing gas is supplied into the heating container on one side (lower side in the embodiment) of the heating means 6. and a gas discharge means 10 for discharging gas from inside the heating container on the other side of the heating means 6. The heating means 6 is.

Any device capable of annularly heating the hollow tube 3 can be used, such as a high frequency induction heating coil, a laser, etc.

The material constituting the heating container 7 is selected according to the heating means 6. When a high frequency induction heating coil is used, a non-magnetic material is used, and when a laser or the like is used, a transparent material is used. This allows the heating means 6 provided outside the heating container 7 to heat the hollow tube section inside the heating container. Note that the heating means 6 is not limited to being provided outside the heating container 7, and may be placed inside the heating container 7.

The sealing means 8 keeps the inside of the heating container airtight even while the heat treatment jig 5 moves along the hollow tube 3.

In the illustrated embodiment, each sealing means 8 includes two sealing rubbers 8a.
, 8b are used. One seal rubber 8a also functions to position the hollow tube 3 at the center of the heating container 5. The sealing means 8 is attached to the sealing rubber 3a by the heat of the hollow tube heated by the heating means 6.

The position is set such that the tube 8b will not deteriorate and the hollow tube 3 exposed outside the heat treatment jig 5 will not be oxidized. The non-oxidizing gas supply means 9 has an annular jacket 9b having a large number of gas injection holes 9a, and a hose 9C for supplying non-oxidizing gas such as argon to the jacket 9b. The gas injection holes 9a are opened at an angle of about 5 to 30 degrees with respect to the center of the heating container 6 when viewed from above so that the injected gas flows spirally on the outer surface of the hollow tube 3. . Like the gas supply means 9, the gas discharge means 10 also has an annular jacket 10b provided with a large number of gas passage holes 10a and a hose 10c. This hose 10C is designed to guide the exhaust gas to a safe place. In the third illustrated embodiment, a gas supply means 9 is arranged below the heating means 6, and a gas discharge means 1O is arranged above it. but,
This may be replaced. When using a gas heavier than air as the non-oxidizing gas, the gas supply means 9 is placed below the heating means 6, and when using a gas lighter than air, the gas supply means 9 is placed above the heating means 6. It is preferable to provide the gas supply means 9 at
It has the advantage of being able to be discharged at zero.

12 is a lower positioning roller, 13 is an upper positioning roller, and 14 is a stopper roller.

FIG. 2 is a side cross-sectional view showing a joint jig 4 that connects the lower end of the hollow tube 3 to the upper end of the lower droplet l. This joint jig 4 has a hollow joint main body 15, and the joint main body 15 has a large diameter part 15A having an outer diameter equal to the outer diameter of the hollow tube 3, and a large diameter part 15A provided at the upper end of the large diameter part 15A to fit inside the hollow pipe 3. It has a first small diameter part 15B, and a second small diameter part 15C, which is provided at the lower end and fits into the lower sachet 1. At the upper end of this joint body 15 is a seal ring having an outer diameter approximately equal to the inner diameter of the hollow tube 3.

For example, an O-ring 16 is disposed, and a hollow core 17 is held within the joint body 15 so as to be movable in the axial direction.

The core 17 has an inclined sealing surface 17A that contacts the O-ring 16 at its upper end, and has a structure in which this sealing surface 17A presses the O-ring 16 against the end surface of the joint body 15 and the inner surface of the hollow tube 3. There is. Note that instead of slanting the sealing surface 17A, the end surface of the joint body 15 is tilted, and when the O-ring 16 is compressed between the joint body end surface and the sealing surface of the core,
The O-ring 16 may be pressed against the inner surface of the hollow tube 3. A sealing surface 17A at the upper end of the core 17 has a large number of holes 17B communicating with the inner diameter side of the O-ring 16, and the sealing surface 17A and A gap 18 is provided between the hollow tube 3 and the inner surface. This hole 17B and gap 18 allow the hollow tube 3
Cooling water or cooling gas inside can flow around the O-ring 16 to cool the O-ring 16. An inner thread 17C is formed on the inner surface of the lower end of the core 17, and a threaded member 19 having an outer thread 19A that engages with the inner thread 17G is rotatably held near the lower end inside the joint body 15. By tightening this screw member 19, the core 17 is tightened in a direction in which its sealing surface 17A approaches the end surface of the joint body 15.

The O-ring 16 can be compressed and pressed against the end face of the joint body 15 and the inner surface of the hollow tube 3. A spear 20 is provided on the part of the joint body 15 facing the hollow tube 3@, and an O-ring 21 for sealing is attached to the upper end surface of the lower droplet l, and a fixing bolt is installed near it. 22 are provided.

In order to connect the hollow pipe 3 to the lower droplet 1 using this joint jig 4, first insert the core 17 containing the O-ring 16 into the joint body 15, and insert the core 17 into the joint body 15 until the O-ring 16 is not crushed by the screw member 19. The tightening is fixed. After this, insert the O-ring 16 side into the end of the hollow tube 3, and firmly tighten the screw member 19 in this state. Due to this force, the O-ring 16 is compressed and strongly tightens against the inner surface of the hollow tube 3. Closely attached.

Enables sealing performance and transmission of strong rotational force. Incidentally, the spear 20 is also useful for transmitting rotational force, and if the necessary rotational force can be transmitted only by the O-ring 16, the spear 20 may be omitted. The second small diameter portion 15C at the lower end of the tool 4 is inserted into the lower droplet 1 and fixed with the fixing bolt 22. Attachment of the hollow tube 3 to the lower droplet 1 is completed when it is 0 or more. A similar operation may be performed to connect the upper dropper 2 to the hollow tube 3.

Next, referring to FIG. 1, a heat treatment operation for the hollow tube 3 installed linearly between the lower sacrificial piece 1 and the upper sacrificial piece 2 will be explained. A non-oxidizing gas such as argon is supplied from the non-oxidizing gas supply means 9 into the heating container 7 of the heat treatment jig 5 provided surrounding a part of the hollow tube 3, and residual air is exhausted from the gas discharging means 10. do. At this time, since the non-oxidizing gas supplied into the heating container 7 flows in a spiral around the hollow tube 3, it is effectively replaced with air, and the inside of the heating container 7 quickly and reliably becomes a non-oxidizing gas atmosphere. Naru 0 normal.

When the non-oxidizing gas is supplied in an amount of 10 to 15 times the internal space volume of the heating container 7 with the gas discharge means 10 open.

Since the inside of the heating container 7 becomes a non-oxidizing gas atmosphere, the heat treatment is started. Cooling water is injected into the interior from the lower droplet 1, the lower droplet 1 is rotated, the rotation is transmitted to the hollow tube 3, and while the cooling water is flowing out from the upper droplet 2, the heating means 6 in the heat treatment jig 5 is heated. The hollow tube is heated locally in an annular manner, and the hollow tube 3 is moved relative to the heat treatment jig 5, or the heat treatment jig 5 is moved relative to the hollow tube 3.

As a result, the heat treatment jig 5 moves relatively along the hollow tube 3, the heated portion moves along the hollow tube 3, and the hollow tube 3 is heat treated. At this time, since cooling water is flowing inside the hollow tube 3 and heating is performed from the outside, the heat treatment is performed with a predetermined temperature gradient created in the thickness direction of the hollow tube 3. Since the part is in a non-oxidizing gas atmosphere, non-oxidizing heat treatment is performed.

In addition, the hollow tube 3 is provided with anti-skid rollers 14 and upper and lower positioning rollers 12, 13, . Since the hollow tube 3 is set at the center of the heating means 6 by the center-holding seal rubber 8a and the like, and the hollow tube 3 is rotating relative to the heating means 6, uniform heat treatment is performed over the entire circumference.

In the embodiment described above, the heat treatment described above can be performed on any location in the longitudinal direction of the hollow tube 3, and can be performed even on the ends of the hollow tube 3, for example. B. Since the end of the hollow tube 3 is connected to the upper and lower droplets 1.2 of the same outer diameter by the joint jig 4 of the same outer diameter, the heating means 6 of the heat treatment jig 5 is connected to the upper and lower ends of the hollow tube 3. until it is located at the end.

The heat treatment jig 5 can be moved to heat up to the end of the hollow tube. Also, at this time, there is an O-ring 16 at the end of the hollow tube, but this O-ring 16 is in contact with the cooling water inside the hollow tube, and compared to the outside temperature of the hollow tube,
Since the temperature is maintained at a significantly low temperature, there is no heat deterioration, and in other words, high temperature treatment of the end portion of the hollow tube is also possible. In addition, when a high-frequency induction heating coil is used as the heating means 6, if the joint body 15 of the joint jig 4 is made of a non-magnetic material such as Cu, the heat generated in this part will be reduced, and the temperature of the O-ring 16 will be reduced. Further, if the O-ring 16 is made of a heat-resistant material such as metal, the heat resistance will further increase, which is preferable. Since the large-diameter portion 15A of the joint body 15 of the joint jig 4 exists between them, the upper and lower shims 1°2 are prevented from being heated to a high temperature when heating the end of the hollow tube. It is also effective in extending the lifespan of the upper and lower droplets.

In addition, in the above embodiment, the case where cooling water was flowed into the hollow tube was explained, but instead of this, cooling gas may be flowed, and the heating portion for heat treatment may be cooled.

This can be achieved with cooling water or cooling gas flowed into the hollow tube, but if necessary, the heating container 7 on the outer periphery of the hollow tube 3 may be used.
A cooling jacket capable of injecting non-oxidizing gas may be provided in the vicinity of the portion heated by the heating means 6, and the non-oxidizing gas for cooling may be sprayed immediately after heating to cool the portion.

〔Effect of the invention〕

As explained above, the heat treatment apparatus of the present invention rotates the hollow tube while flowing a cooling fluid inside the tube, and during the rotation, the heat treatment jig is moved relative to the hollow tube along the hollow tube. It is possible to move the hollow tube.

Uniform heat treatment can be performed with a temperature gradient generated in the thickness direction. Furthermore, when the heat treatment jig moves relatively while heating the hollow tube, the heated portion of the hollow tube is surrounded by a heating container and sealing means at both ends of the heating container, and non-oxidizing gas is supplied to that space. Therefore, it is also possible to subject hollow tubes to non-oxidizing heat treatment. Furthermore, the heating container used to create an oxidation-free atmosphere only needs to be large enough to surround only the parts that are likely to be oxidized by heating when the hollow tube is heated for heat treatment, making the entire device more compact. In addition, the amount of non-oxidizing gas consumed can be reduced, and equipment costs and running costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view showing an embodiment of the present invention, and FIG. 2 is a partially sectional side view showing an enlarged joint jig 4 used in the embodiment. DESCRIPTION OF SYMBOLS 1...Upper droplet 2...Upper droplet 3...Hollow tube 4...Jointing jig 5...Heat treatment jig 6...Heating means 7-...Heating container 8...Sealing means 9... Non-oxidizing gas supply means 9a-... Gas injection hole lO... Gas discharge means 15... Joint body 15
A-...Large diameter part 15B-...First small diameter part 15C...
・Second small diameter part 16...0 ring 17...core
17A...Seal surface 19-・Screw member representative Patent attorney Kyo Matsu 3rd figure 1st figure 2nd figure

Claims (3)

[Claims] (1) A hollow lower sachet and an upper sachet that are rotatably arranged on a substantially vertical straight line, the lower end of the hollow tube to be heat treated is placed on the upper end of the lower sachet, and the upper end of the hollow tube is placed on the upper sachet. a pair of joint jigs connected to their lower ends in a sealing relationship and capable of transmitting rotational force, and a heat treatment jig that is relatively movable along a hollow tube installed between the lower and upper sachets. The heat treatment jig includes a heating means for annularly heating the hollow tube, a cylindrical heating container surrounding a portion of the hollow tube heated by the heating means, and disposed at both ends of the heating container. a sealing means for sealing between the heating container and the hollow tube; a non-oxidizing gas supply means for supplying non-oxidizing gas into the heating container on one side of the heating means; and a non-oxidizing gas supply means on the other side of the heating means. 1. A heat treatment apparatus for hollow tubes, comprising: a gas discharge means for discharging gas from the inside of the heating container. (2) The non-oxidizing gas supply means has a gas injection hole that is inclined with respect to the center of the heating container so as to generate a spiral gas flow inside the heating container. The heat treatment apparatus for hollow tubes according to item 1. (3) The coupling jig includes a large diameter part having an outer diameter equal to the outer diameter of the hollow tube, a first small diameter part provided at one end thereof and fitting into the hollow tube, and an upper part provided at the opposite end. a hollow joint body having a small-diameter portion that fits into the sachet or the lower sachet; a seal ring disposed on the end face of the first small-diameter portion of the joint body and having an outer diameter approximately equal to the inner diameter of the hollow pipe; The core includes a core that is held movably in the axial direction with respect to the joint body and has a sealing surface that contacts the seal ring, and a screw member that tightens the core in a direction in which the sealing surface approaches the joint body. and when the core is tightened in a direction in which its sealing surface approaches the end surface of the joint body, the sealing surface compresses the seal ring and presses it against the end surface of the joint body and the inner surface of the hollow tube. A heat treatment apparatus for hollow tubes according to claim 1 or 2, characterized in that: