JPH0343326B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an apparatus for hardening so-called long materials such as steel pipes, and in particular, a rotary hardening method in which the material to be hardened is cooled while rotating around its axis. It is related to the device.

Conventional Technology For example, when quenching a steel pipe, if a red-hot steel pipe is simply immersed in cooling water, a steam film due to the boiling of the cooling water will irregularly cover the surface of the steel pipe, or the outer circumferential surface of the steel pipe may A situation may arise in which the portion of the material that is in contact with the pedestal is not cooled, resulting in the inconvenience that uniform hardening cannot be achieved. Further, a similar problem occurs in a cooling method in which cooling water is injected onto red-hot steel pipes.

Conventionally, a rotary hardening apparatus has been known as an apparatus that can eliminate the above-mentioned disadvantages. This system uses a rotationally driven turning roller and a pinch roller that approaches and moves away from the turning roller to pinch the material to be hardened, such as a steel pipe, and cool it while rotating around its axis. Compared to the case where the material to be quenched is left to cool, more uniform quenching can be achieved.

In addition, conventional steel pipe quenching equipment was
This method uses a clamp mechanism to grip the end of a steel pipe that is rotatably supported by a clamp roller, and rotates the steel pipe using these clamp rollers and the clamp mechanism. The structure is such that cooling water is injected onto both the inner and outer circumferential surfaces of the steel pipe to harden it while reciprocating in the axial direction.

Problems to be Solved by the Invention However, in the conventional rotary hardening apparatus described above, the lower pair of turning rollers 1a, 1b and the upper pair of pinch rollers 2a, 2b are arranged as shown in FIGS.
As shown in the figure, since they are arranged in the same plane along the radial direction of the steel pipe 3, these turning rollers 1 are located on the outer peripheral surface of the steel pipe 3.
a, 1b and the portions that contact the pinch rollers 2a, 2b, even if the steel pipe 3 is rotated,
The degree of contact with the cooling water was lower than that of other parts, and as a result, the cooling of the steel pipe 3 as a whole became uneven, and in extreme cases, there was a high possibility that the steel pipe 3 would be bent significantly. Furthermore, conventional rotary hardening equipment generally has a configuration in which the turning rollers 1a and 1b are fixed, and the pinch rollers 2a and 2b are moved up and down to pinch the steel pipe 3 and release the pinching. However, when setting the pinch rollers 2a, 2b when starting hardening, the axes of the pinch rollers 2a, 2b are aligned with the steel pipe 3 as shown in FIG.
If the pinch rollers 2a, 2b are not parallel to the axis of the
With the rotation of the steel pipe 3, a thrust force is generated along the axial direction of the steel pipe 3, and as a result, the steel pipe 3 moves in the axial direction, causing a change in the relative position between its end and the inner nozzle 4. There was a problem that the required amount of cooling water could not be obtained and the steel pipe 3 would bend.

On the other hand, in the quenching apparatus according to the above-mentioned Japanese Patent Application Laid-Open No. 57-185924, the target steel pipe is simultaneously rotated and actively reciprocated in its axial direction.
Even the parts hidden behind the clamp rollers can be cooled, allowing for uniform hardening. However, in the apparatus according to the above proposal, since the end portion of the steel pipe is continuously held by the clamp mechanism, there is a problem in that the end portion of the steel pipe is insufficiently quenched. In addition to the mechanism for reciprocating the steel pipe in the axial direction, it is also necessary to have a mechanism to stably supply cooling water to the inner surface of the steel pipe even when it moves in the axial direction, so the equipment as a whole is large-scale. Another problem was that it was expensive.

Means for Solving the Problems In order to achieve the above object, the present invention provides that each of a plurality of sets of holding mechanisms provided to rotatably hold a material to be hardened such as a steel pipe is connected to two lower rollers. and two upper rollers that approach and separate from the lower roller.
The two lower rollers are arranged offset from each other in the axial direction of the material to be hardened, and each of the two upper rollers is arranged so as to be substantially opposed to each lower roller on the diameter of the material to be hardened. The holder, which is arranged offset from each other in the axial direction of the material and to which the upper roller is rotatably attached, is moved close to and away from the lower roller so that it can rotate freely around the axis along the radial direction of the upper roller. It is characterized by being attached to a movable seat.

Function Therefore, in the rotary hardening apparatus of the present invention, at specific locations on the outer circumferential surface of the material to be hardened, one
Since only one roller is in contact with the other to support and rotate the material to be quenched, the area covered by the rollers at a specific location on the outer circumferential surface is reduced. In addition, by making the holder to which the upper roller is attached freely rotatable around the axis along the radial direction of the upper roller, the external force accompanying the rotation of the material to be quenched is balanced, and the upper roller is attached to the material to be quenched. It is automatically set to be parallel to the quenching material, so no thrust is generated in the axial direction of the material to be quenched.

Embodiment Next, an embodiment of the present invention is shown in FIGS. 1 to 3.
This will be explained with reference to the figures. FIG. 1 is a schematic diagram showing an embodiment of the present invention, in which a steel pipe 10 as a material to be quenched is held substantially horizontally by a plurality of holding mechanisms 11 and rotated around its axis. In this state, the steel pipe 10 is immersed in cooling water, or cooling water is injected from the outer circumferential side, and a flow of cooling water is applied to the inside to perform quenching.
As shown in FIGS. 2 and 3, each holding mechanism 11 includes two lower rollers 12a, 12b and two corresponding upper rollers 13a, 13b. The lower rollers 12a, 12b are arranged slightly offset from each other in the axial direction of the steel pipe 10, and are attached to mutually parallel rotating shafts 15a, 15b rotated in the same direction by the motor 14. Therefore, the lower rollers 12a and 12b serve as turning rollers on which the steel pipe 10 is placed and rotated. On the other hand, the upper rollers 13a, 13b are pinch rollers that press the steel pipe 10 against the lower rollers 12a, 12b. They are placed almost facing each other. That is, the upper rollers 13a and 13b are the steel pipes 10
are arranged slightly shifted from each other in the axial direction, one upper roller 13a is substantially opposed to one lower roller 12a on the diameter of the steel pipe 10, and the other upper roller 13b is opposed to the other lower roller 12b. They are arranged so as to be substantially opposed to each other on the diameter of the steel pipe 10. Further, as shown in FIG.
Pins 17a and 17b so that their axes are horizontal to 6b.
The holders 16a, 16b are rotatably attached to the upper rollers 13a, 13b.
The movable seat 19 is rotatably attached to the lower surface side of the movable seat 19 via rotating shafts 18a and 18b facing in the radial direction. Therefore, each upper roller 13a, 13b rotates around a horizontal axis, that is, pin 17a, 17b, and rotates around a vertical axis, that is, rotation axis 18a, 1.
It is configured to rotate around 8b. Further, the movable seat 19 is attached to the rod tip of a hydraulic cylinder 20 which is arranged above the movable seat 19 and faces downward.
Furthermore, in order to move the movable seat 19 up and down while keeping it in a horizontal state, two guide rods 21 are provided upright on the upper surface of the movable seat 19.
1 is slidably inserted into the guide bush 22.

Next, the operation of the device configured as described above will be explained. With the upper rollers 13a and 13b pulled up together with the movable seat 19 by the hydraulic cylinder 20, the steel pipe 10, which has been red-hot in advance, is moved to the lower roller 12.
Place it on top of a and 12b. Then upper roller 13
a, 13b are lowered by the hydraulic cylinder 20, the steel pipe 10 is moved between the upper and lower rollers 12a, 13b.
The steel pipe 10 is rotated by holding it between the lower rollers 12b, 13a, and 13b and rotating the lower rollers 12a and 12b by the motor 14.
In this state, the steel pipe 10 is immersed in cooling water, or cooling water is injected from the outer surface, and a cooling water flow is applied to the inner surface to perform quenching.

In such a cooling process, a specific location on the outer circumferential surface of the steel pipe 10 comes into contact with the roller repeatedly, but in the above-mentioned device, the lower roller 12
Since the rollers a and 12b and the upper rollers 13a and 13b are shifted from each other in the axial direction,
There are a total of two rollers that come into contact with a specific location on the outer peripheral surface, one lower roller 12a (or 12b) and one upper roller 13a (or 13b),
Therefore, even if a specific location on the outer circumferential surface repeatedly contacts the roller, the extent to which it is hidden from the cooling water by the roller is small, so that it is cooled as necessary and sufficient as other locations. That is, steel pipe 1
The entire outer circumferential surface of the 0 can be cooled uniformly.
Further, in the above device, the upper rollers 13a, 13b are configured to be able to freely rotate around the rotating shafts 18a, 18b. , becomes parallel to the steel pipe 10 by an external force such as frictional force, and misalignment during setting or misalignment due to uneven wear can be automatically corrected. Therefore, in the above device, even if a thick-walled pipe is cooled for a long time, the steel pipe 10 will not move in the axial direction due to thrust during cooling, and even if the inner nozzle is arranged at the end of the steel pipe 10, Even if they are set, their relative positions do not change.

Effects of the Invention As is clear from the above explanation, according to the rotary hardening apparatus of the present invention, the upper and lower rollers are arranged so that one roller each is positioned at the same cross-sectional position along the radial direction of the material to be hardened. Because of this arrangement, the degree to which specific parts of the outer circumferential surface of the material to be quenched are hidden from the cooling water by the rollers that hold and rotate the material to be quenched is extremely small, thus reducing unevenness in heating and hardness. It is possible to perform uniform hardening without causing unevenness, and to obtain a product without bending. Moreover, since the apparatus of the present invention does not require reciprocating the material to be hardened in the axial direction, the structure can be simplified.
In addition, by configuring the upper roller, which is a pinch roller, to rotate around its radial axis, misalignment of the upper roller with respect to the material to be quenched is automatically corrected, and therefore the rotational force is reduced. Since no thrust force is generated in the axial direction of the material to be quenched, even when the material to be quenched, such as thick-walled products, requires long rotation and cooling, there is no thrust in the axial direction of the material to be quenched. There is no movement, so there is no change in the relative position with the nozzle that supplies cooling water to the inner surface, and as a result, uniform cooling can be achieved from both the inner and outer surfaces, making it possible to obtain a product without bending. Become.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing one embodiment of the present invention, Fig. 2 is a front view showing an example of the holding mechanism, Fig. 3 is a view taken along the - arrow in Fig. 2, and Fig. 4 is a conventional rotation FIG. 5 is a schematic view showing the arrangement of rollers in the hardening device, FIG. 5 is a view taken along the line - in FIG. 4, and FIG. 6 is a schematic view showing a state where misalignment has occurred. 10... Steel pipe, 11... Holding mechanism, 12a, 1
2b...Lower roller, 13a, 13b...Upper roller, 16a, 16b...Holder, 18a, 18b
...Rotating axis, 19...Movable seat.

Claims (1)

[Claims] 1 Supports a cylindrical or columnar material to be hardened 2
It has multiple sets of holding mechanisms each consisting of a lower roller and two upper rollers that approach and move away from the lower roller, and the material to be hardened is held and rotated by the holding mechanism. In the rotary hardening apparatus configured to perform cooling, the two lower rollers are arranged offset from each other in the axial direction of the material to be hardened, and
Each of the upper rollers is disposed offset from each other in the axial direction of the material to be quenched so as to substantially oppose each of the lower rollers on the diameter of the material to be quenched, and each of the upper rollers is The holder is rotatably attached to the tool, and the holder is attached to a movable seat that moves toward and away from the lower roller so as to be rotatable about the axis along the radial direction of the upper roller. Characteristic rotary hardening equipment.