JPS5927320B2 - Automatic sheathing and separation equipment for externally coated steel pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automatic sheath cutting and separation device for coated steel pipes;
More specifically, the present invention relates to an apparatus for continuously applying a coating of polyethylene or the like to the outer circumferential surface of steel pipes connected by a joint, and then cutting the coating at the joint to separate the steel pipes.

Coating work for externally coated steel pipes involves connecting the ends of the steel pipes with connectors to prevent mutual misalignment, and then continuously transporting the steel pipes in the axial direction. This is done by covering the steel pipe with a coating material such as polyethylene.

In this way, when the steel pipes are connected and their outer surfaces are coated continuously, the outer skin is also continuous, so it becomes necessary to cut it and separate the steel pipes.

Conventionally, there are two ways to cut the outer skin: mechanically and manually. The mechanical cutting method is for small-diameter steel pipes, and when the joints of the steel pipes are detected using an eddy current detector, a trolley is run at the same speed as the steel pipe, and a heat knife attached to the trolley is used to cut the joints. Press it against the outer skin of the part,
They apply heat to cut it.

However, such a device has a problem that it has a complicated structure and is large in size, has high equipment costs and operating costs, and requires a large working space. In addition, the artificial cutting method is for large-diameter steel pipes, and involves visually checking the joints and manually cutting the joints with a knife.

Such manual work is not only inefficient but also dangerous. In addition, applying the automatic cutting equipment for small diameter pipes to large diameter steel pipes has problems such as the equipment becomes large, equipment costs increase, and the steel pipe line speed has to be slowed down, resulting in high work costs. However, it can be said that its implementation is almost impossible. This invention was made to solve the above-mentioned problems, and by incorporating a cutter into the joint that connects the ends of steel pipes, it is possible to safely and economically cut the outer skin of large-diameter steel pipes. The purpose is to enable cutting to be performed automatically.

The basic structure of this invention is to incorporate a blade that can expand and contract freely into a joint that connects the ends of steel pipes, push this blade outward with a cone, and cut the outer skin at the connecting part after cooling and solidifying it. It is something to do.

Hereinafter, the present invention will be explained based on embodiments shown in the accompanying drawings. As shown in the figure, the connector main body 2 that connects the externally coated steel pipes 1 and 1 on both sides includes connector units 3 and 4 that are inserted separately into both steel pipes 1 and 1, and a fixture that connects the two units. It consists of a shaft 5.

The above-mentioned connectors 3 and 4 have a cylindrical shape with a tapered tip so that it can be easily inserted into the steel pipe 1, and the steel pipe 1 is attached to the outer peripheral surface of the rear end.
It is provided with a flange 6 for receiving the end of the steel pipe 1, and is formed to fit into the steel pipe 1 so as to be freely inserted into and removed from it, and disc-shaped cover plates 7 and 8 are provided inside the flange 6.

Both connectors 3 and 4 have their rear ends provided with flanges 6 aligned with each other, and with an appropriate gap 9 formed between the rear ends, are inserted between the cover plates 7 and 8 along the axis. They are connected by a fixed shaft 5 installed along the line.

The steel pipes 1 and 1 connected by the connector main body 2 are coaxial as shown in Fig. 1, and a gap is maintained by contact with the flange 6, and the coating applied to the outer surface is maintained. The outer skin 10 is applied continuously over both steel pipes 1 and 1, and also covers the outside of the gap 9 portion, and this portion will be cut by a cutter described later. A hollow screw shaft 1 is rotatably fitted onto the outside of the fixed shaft 5 while being supported by a bearing 12, and a gear 13 connected to one end of the screw shaft 11;
A gear 15 attached to the output shaft of a motor 14 fixed in the joint main body 3 is interlocked via an idle gear 16 pivotally fixed to the cover plate 7, and the activation of the motor 14 gives forward and reverse rotation to the screw shaft 11. It is now possible to do so.

A cone 17 is externally screwed onto the screw shaft 11.

This cone 17 is formed into tapered surfaces 1 and 8 whose outer circumferential surface faces the connector unit 3 and has a smaller diameter, and a female thread 19 formed on the inner circumferential surface is screwed into a male thread 20 of the screw shaft 11. When the screw shaft 11 is rotated without rotating the cone 17, the cone 17 moves in the axial direction. The tapered surface 18 of the cone 17 is formed, for example, in a hexagonal cross section as shown in FIG. 2, and a dovetail groove 21 is provided on each surface along the axial direction. Expansion procks 22 are arranged on the outer side of each tapered surface 18 of the cone 17 at positions on the same circumference.

As shown in FIG. 2, this block 22 is formed in a hexagonal shape close to a fan shape, and has a protrusion 23 that engages with the dovetail groove 21 at the inner end formed on an inclined surface equal to the tapered surface 18. A protrusion 24 along the radial direction of the joint unit 3 is provided on the side surface of each of the expansion procks 22 facing the joint unit 3, and a dovetail groove 25 in which the projection 24 engages is provided in the joint unit unit 3. Fixed guides 26 with mounting ribs 27 are provided in a radial arrangement.

The group of expansion blocks 22 can freely perform diffusion and collective movement in the radial direction around the fixed shaft 5 by engaging with the fixed guide 26, and this diffusion and collective movement can be achieved by moving the cone 17 back and forth. It turns out.

As shown in FIG. 1, the expansion proc 22 is held by a fixed guide 26 so as to face exactly the gap 9 between the connecting devices 3 and 4, and the cone 17 is held by the expansion proc 22. The fixed guide 26 is held in a non-rotating state by the handle rib 27, and is moved forward and backward in the axial direction by the rotation of the screw shaft 11. A fan-shaped plate-shaped blade 28 is fixed to the outer end of each expansion block 22. As shown in FIG. 2, each of the blades 28 has a circular cutting edge on its outer periphery, and is arranged so that its ends overlap alternately with adjacent blades to form a disk as a whole. The cutting edge of the cutting tool 28 faces the gap 9 as shown in FIG. Located inside, cone 17
When the expansion proc 22 is expanded on the larger diameter side, the cutting edge will expand and protrude outward from the gap 9 to cut the outer skin 10.

Note that if the blade 28 is heated using a heater or the like, the cutting effect of the outer skin 10 will be further improved.
A battery 29 for driving the motor 14 is built into the connector main body 2, and a timer 30 is provided in the middle of an electric circuit connecting the battery 29 and the motor 14. This timer 3
0 is for cutting by rotating the motor 14 by setting the time from the coating process to cutting the outer skin 10 in advance or by operating it by remote control or wirelessly. The cutting of the outer skin 10 need only be carried out after the cooling and solidification has progressed to a certain extent and before the separation roller immediately before the cross-feeding skid that feeds the steel pipes 1, 1, and there is no particular need for precision in the cutting timing. It is sufficient to start the motor 14 with the setting of the timer 30, taking into consideration the line speed, the hardening time of the outer skin, and the distance to the separating roller.

The cutting and separating device of the present invention has the above-mentioned configuration, and with the timer 30 set to a predetermined time, the joining tools 3 and 4 on both sides are inserted into each of the steel pipes 1 and 1, and are connected by the joining tool main body 2. The steel pipes 1, 1 are moved and the outer surfaces are coated along the way. When the outer skin 10 is cooled and solidified, the timer 30 is activated and the motor 14 is energized, so that the T-motor 14 starts and rotates the hollow screw shaft 11, and the cone 17 moves to the right in FIG. Push out the expansion block 22.

The diameter of the cutting edges of the group of blades 28 attached to each block 22 is expanded, and the outer skin 10 covering the gap 9 is cut by the cutting edges. When the cutting is completed, the motor 14 rotates in the reverse direction and moves the cone 17 to the left in FIG. If the steel pipes 1, 1 are separated from each other, they will come out of the joint body 2. As described above, since the present invention has the above configuration, it has the following effects.

Since the outer coated skin can be cut with a knife using a joint that connects one steel pipe, the work can be done without touching the steel pipe directly, and safety can be improved through automation.

Since two joints are used, it is not only possible to downsize, but also to reduce equipment costs, making it economical.

Since each member is housed in three joints, the whole is compact, and automatic cutting can be realized, especially for large diameter steel pipes.

Since the motor is started with a 4-timer, cutting can be performed in the most suitable condition for cutting the outer skin.

Since the 5-screw shaft, cone, and expansion block are used, each blade can be expanded and assembled accurately.

Note that the connector alone is not limited to a cylindrical shape with a tapered tip end as shown in Figure 1; for example, it can be split into two parts and biased in the diametrical direction by an elastic device such as a spring. If this is done, the outer circumferential surface of the joint tool alone will press against the inner circumferential surface of the steel pipe by this bullet when it is set into a steel pipe, allowing for more complete setting. It goes without saying that instead of the timer, a switch that can be turned on and off by remote control may be provided in the electric circuit connecting the battery and the motor, so that the device of the present invention can be operated from the outside.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of a cutting and separating device according to the present invention, and FIG. 2 is a sectional view taken along the arrow - in FIG. 1 is a steel pipe, 2 is a connector main body, 3 and 4 are connectors, 5 is a fixed shaft, 6 is a flange, 9 is a gap, 10 is an outer skin, 11 is a hollow screw shaft, 14 is a motor, 17 is a cone, 18 is a tapered surface, 19 is a female thread, 20 is a male thread, 21 is a dovetail groove, 22
2 is an expansion block, 23 and 24 are protrusions, 25 is a dovetail groove, 2
6 is a fixed guide, 27 is a mounting rib, 28 is a knife, 29 is a battery, and 30 is a timer.

Claims (1)

[Claims] 1 A screw shaft supported rotatably along the axial direction of the main body in a joint body for connecting externally coated steel pipes, a motor that rotates the screw shaft in forward and reverse directions, and this motor. a drive source, a cone screwed onto the screw shaft so as to be able to move forward and backward in the axial direction, and having a plurality of dovetail grooves along the axial direction on the tapered surface of the outer periphery; and an inner end disposed on the outside of the cone. is fixed to a plurality of expansion blocks that are engaged with the dovetail grooves and to the joint body, and each expansion block can be freely spread and collected in the radial direction of the joint body by moving the cone back and forth. a plurality of blades attached to the outer ends of each of the expansion blocks and arranged in a disc shape with adjacent ends overlapping each other; 1. An automatic sheath cutting and separation device for externally coated steel pipes, characterized by incorporating a timer connected between a drive source.