JPS6342115Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an apparatus for manufacturing an electric resistance welded steel pipe, and more particularly to a water cooling device for a seam portion of an inner surface of a tube for heat treatment when manufacturing a high strength electric resistance welded steel pipe.

When manufacturing high-strength electric resistance welded steel pipes, a heat treatment is performed in which the weld seam is annealed, then normalized, and then quenched in order to improve the strength of the welded seam. Conventionally, quenching in this heat treatment has generally been carried out by water-cooling the weld seam only from the outside of the pipe, and cooling from the inside of the pipe has not been done because it is difficult to target the seam. Nakatsuta.

However, with such cooling only from the outside of the pipe, there is a limit to the amount of heat removed by the cooling water injection, which makes it impossible to obtain the necessary cooling rate near the inside of the pipe, especially for thick-walled pipes, which reduces the effectiveness of heat treatment. The problem was that I couldn't give enough.

This idea was made in view of the above-mentioned conventional circumstances, and even when processing thick-walled pipes, it is possible to obtain the necessary cooling rate even for the inner surface of the pipe, and it is possible to obtain a high-strength electric current at the welded part. It is an object of the present invention to provide a water cooling device for the inner seam portion of an electric resistance welded steel pipe, which can produce a welded steel pipe.

In other words, the water cooling device for the internal seam of an ERW steel pipe according to this invention has rolls at the bottom and both sides, and the spray nozzle is mounted on a spray nozzle mount whose center of gravity is below the rolls on both sides. The spray nozzle mount is installed so as to face vertically above the center of gravity, and the spray nozzle mount is supported by a long body whose one end is supported at a position rearward of the welding point to the pipe along the pipe traveling direction, and The spray nozzle is characterized in that a water pipe introduced into the pipe from a position behind the welding point is connected to the spray nozzle.

An embodiment of this invention will be described below with reference to FIGS. 1 to 5.

The pipe 1 shown by the broken line in FIG. 1 is fed from the fin pass roll 2 to the squeeze roll 3 in an open pipe state, and during that time, the open pipe edge is heated and melted by the welding machine 4 at a position immediately before the squeeze roll 3. The welded seam is formed by compressing the molten edge with the squeeze roll 3. After the bead of the weld seam is cut by a cutter 5, it is heated by induction by a seam annealer 6, and then water-cooled by an outer water cooling device 7 and an inner seam water cooling device 8 of this invention.

The inner seam water cooling device 8 has a spray nozzle mount 9, and a mandrel bar 1 as a long body with one end attached to the spray nozzle mount 9.
The other end of 0 is fixed to a support frame 11 inserted into the pipe 1 through a gap at the edge of the open pipe between the fin pass rolls 2 located behind the welding machine 4 along the traveling direction of the pipe 1. has been done.

As shown in FIG.
has a side roll 15, with its bottom 12 and side 1
A spray nozzle 17 is arranged inside 4. Furthermore, this spray nozzle frame 9 has a center of gravity G of the entire weight of the spray nozzle frame 9, as shown in the figure, the side roll 15
The weight of the material is selected for the bottom 12 so that it lies in the bottom 12 of the bottom 12 . Also, the mouth portion 17a of the spray nozzle 17
The bottom part 1 should face in the same direction as the direction directly above the center of gravity G.
It is located on 2.

The mandrel bar 10 is supported at its midpoint by a cutter head 18 having a cutter 5, and the cutter head 18 is disposed within the pipe 1 with a roll 19 as shown in FIG. Further, the mandrel bar 10 itself is hollow inside as shown in FIGS. 2 and 4, and the support frame 1 of the mandrel bar 10 is
A pressure-resistant hose 2 inserted into the pipe 1 from between the fin pass rolls 2 through the gap at the open pipe edge part is inserted into the internal cavity near the fixing part for the pipe 1.
Further, as shown in FIG. 3, bypass water pipes 21 are provided on both sides of the cutter head 18, and the bypass water pipes 2
1 are communicated with the inner cavity of the mandrel bar 10 at the front and rear of the cutter head 18.
Further, the mandrel bar 10 in front of the cutter head 18 is directly connected to the spray nozzle 17, and the spray nozzle 17 is connected directly to the spray nozzle 17 by the pressure hose 20, the bypass water conduit 21, and the inner cavity of the mandrel bar 10 before and after the cutter head 18.
Water pipes will be constructed.

As shown in FIG. 1, a pipe 1 is located below the bottom roll 13 of the spray nozzle frame 9.
A fixed support roll 22 is disposed through the tube wall.

Therefore, if the above inner seam water cooling device 8 is used, the inner seam of the pipe 1 is cooled by injecting high pressure water supplied from the pressure hose 20 from the nozzle port 17a of the spray nozzle 17. be able to. At that time, as mentioned above, the center of gravity G of the spray nozzle frame 9 is
Since the nozzle port 17a is located at the bottom 12 below the mandrel bar 10 and faces in the same direction as the vertically upward direction of the center of gravity G, even if the mandrel bar 10 suddenly becomes twisted, it can be automatically Specifically, the spray nozzle frame 9 is centered, and cooling water is always sprayed from the nozzle opening 17a of the spray nozzle 17 toward the inner seam of the pipe 1.

During the cooling process for the inner seam of the pipe 1, the spray nozzle frame 9 is held in place by being pulled by the mandrel bar 10 while the side rolls 15 roll on the inner surface of the pipe 1. On the other hand, when the coil is off, that is, after the pipe 1 currently being processed passes and until processing of the next pipe starts, the spray nozzle mount 9 is in a state where the bottom roll 13 rolls on the fixed support roll 22. and is held in place by a mandrel bar 10.

As described above, according to the water cooling device for the inner seam part of an ERW steel pipe of this invention, the spray nozzle can be held in a fixed position during the treatment of the inner seam part of the pipe during the processing stop, and the nozzle of the spray nozzle can be Cooling water is always sprayed from the mouth, aiming at the inner seam of the pipe.
It is possible to cool the seam part of the ERW steel pipe from the inner surface, and it is possible to achieve a sufficient heat treatment effect even for thick-walled pipes, and to obtain ERW steel pipes with high strength at the welded seam part, regardless of whether the pipe is thin or thick. be able to.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a condition in which the inner seam part of an ERW steel pipe after normalization is water-cooled using a pipe inner seam water cooling device according to an embodiment of this invention, and Fig. 2 is a diagram showing the state in which the inner seam part of an ERW steel pipe after normalization is water-cooled. 3 is a sectional view taken along the line of FIG. 1, FIG. 4 is a sectional view taken along the line of FIG. 1, and FIG. 5 is a sectional view taken along the line of FIG. 1. 9... Spray nozzle mount, 10... Mandrel bar, 11... Support frame, 13... Bottom roll, 15... Side roll, 17... Spray nozzle, 17a... Spray nozzle mouth, 20...
Pressure resistant hose, 21... Bypass water pipe.

Claims (1)

[Scope of utility model registration request] Attach the spray nozzle to a spray nozzle stand that has rolls on the bottom and both sides, and whose center of gravity is below the rolls on both sides, so that the nozzle opening faces in the same direction as vertically above the center of gravity of the spray nozzle stand. The spray nozzle mount is supported by an elongated body whose one end is supported at a position rearward of the welding point to the pipe along the pipe traveling direction, and a feeder is introduced into the pipe from a position rearward of the welding point to the spray nozzle. A water cooling device for the inner seam part of an ERW steel pipe, characterized by connecting water pipes.