JPH02124258A - Traction type polishing device for pipe inner face - Google Patents

Abstract

PURPOSE:To travel the bent part, cut and fitted part, dresser joint part, dislocation step difference part, etc., of a pipe line stably and smoothly without any inconvenience by providing a main body support 1 caterpillar plurally projected radially like sliding with the pipe inner face and elastically supporting the main body at the oder peripheral end part of a disk shaped device main body in smaller diameter than the pipe inner diameter. CONSTITUTION:A device main body 1 is made in the structure to be tracted by an automatic traveling device via a tracting joint provided at both ends of a spline shaft 3 projected in the pipe axial line to the main body center part. This main body 1 travels inside the pipe by plural main body supporting caterpillars 2 provided at the radial position on the outer peripheral end part. In case of grinding the welding bead of the pipe inner peripheral face by this traveling grinder, a rotating cylindrical body 4 is rotated via gears 4-9, 4-5 by driving motors 4-8 fitted integrally with the rotating cylindrical body 4. Also, in case of moving the grinder in the pipe axial direction, the motors 4-10 are driven and the rotating cylindrical body 4 of the above of the spline shaft 3 is moved.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an apparatus suitable for polishing the inner surface of pipes such as underground pipes that have many bent pipe parts and many joints. Repair welding from the inside,
The present invention also relates to a towed tube inner surface polishing device suitable for cutting and polishing unevenness on the inner surface of the tube and the welded part when welding from the inner surface of the tube in order to install a new pipe.

[Conventional technology]

As a polishing device for the inner surface of a tube, the main body of the device is generally a trolley type, and the following types of polishing mechanisms are known as typical polishing mechanisms. (a) A method in which an arm equipped with an air grinder with a polishing sump is rotated, bent, and moved forward and backward by a motor while moving inside the pipe to repair surface flaws in the bead grinder inside the pipe. (b) A method in which an air grinder is attached to the end of the rod of an air cylinder, and the air cylinder presses the grinder against the inner surface of the tube for polishing. (C) Connect the rod of the air cylinder attached to the device body to one end of the seesaw member, attach an electric milling cutter to the other end, and press the milling cutter against the inner surface of the tube by moving the air cylinder rod back and forth to cut the bevel. method. (d) A method in which an electric grinder is attached to a spline shaft rotated by an electric motor, the rotational torque of the grinder is detected by a current sensor, and this is controlled in conjunction with the forward and reverse rotation of the spline shaft rotation motor to perform grinding. However, these polishing and grinding methods have the following drawbacks. Method (a) requires a long arm to ensure a contact angle between the sander attached to the air grinder and the inner surface of the pipe, and the trolley that moves inside the pipe becomes longer, so the buried pipe is installed underground for a long time. It is not suitable for pipes that have bends (elbows) or cuts in the middle of the pipe, such as in pipes. In addition, the pressure contact force between the sander and the inner surface of the tube is adjusted by detecting the bending stress of the arm using a sensor and driving the motor to move the sander up and down based on the stress value, but it is difficult to make minute movements of the sander. When the pressing force exceeds the air motor output torque, the sander rotation will stop, so this situation will be observed on the monitor TV while grinding. However, this system has the disadvantage that when the pipe is long, from 50 to 100 m, the pressure loss is large, and in order to reduce this, an air hose with a large diameter is required, which impairs the tractability of the device. In the method (b), the pressure contact force between the sander and the inner surface of the tube is adjusted by an air cylinder, so in this case as well, as in the method (a) above, it is difficult to make minute movements of the sander, and the air pumping loss is large. There is a drawback. Method (C) requires checking the rotational torque limit of the electric motor that rotates the milling cutter, which results in poor smoothness of the grinding surface, and also requires adjusting the air cylinder rod forward and backward during milling. There is a drawback that the milling cutter may become jammed if it is not done accurately. Method (d) has no problem when grinding relatively smooth surfaces, but has the disadvantage that it cannot be applied when grinding weld beads or localized unevenness because the spline must be rotated frequently between forward and reverse rotations. be.

[Problem to be solved by the invention]

This invention was developed in view of the actual situation described above, and was developed to prevent weld beads and irregularities on the inner surface of pipes where there are bends or cuts in the middle of the pipe, such as long underground pipes. We are trying to propose a tube inner surface polishing device that can polish efficiently, solves the problem of air pressure loss by using an electric grinder, and also has the function of easily and accurately adjusting the pressure contact force of the polishing wheel. It is something. [Means for Solving the Problems] The present invention adopts a plurality of caterpillars in the tube support system of the device main body, and has a mechanism that can drive the electric grinder in the tube radial direction, the tube axis direction, and the tube circumferential direction, Furthermore, a method is adopted in which the electric grinder's pressure contact force on the inner surface of the pipe is controlled by adjusting the pressure of the air buffer tank. That is, the gist of the present invention is to provide a plurality of main body supporting caterpillars which are provided on the outer circumferential end of a disc-shaped device main body having a smaller diameter than the inner diameter of the tube and project radially so as to come into sliding contact with the inner surface of the tube, and resiliently support the device main body. A rotary whetstone that is moved forward and backward in the radial direction of the tube by an air cylinder connected to an air buffer tank is attached to a rotating cylinder that is fitted onto a spline shaft that protrudes from the center in the direction of the tube axis and is driven forward and backward and rotated by a motor. This is a towed tube inner surface polishing device equipped with a light for imaging inside the tube, a television camera, and a joint for towing the device.

[For production]

The main body of the apparatus has a structure in which it is towed by an automatic traveling device via traction joints provided at both ends of a spline shaft protruding from the center of the main body in the direction of the tube axis. The main body of the apparatus travels inside the pipe by a plurality of main body supporting caterpillars provided at radial positions on the outer peripheral end thereof. The reason why caterpillars are used as the in-pipe traveling support means of the main body of the device is to enable smooth travel over uneven parts such as pipe wall separation parts such as dresser joints, bends, and weld beads in the middle of piping. The main body supporting caterpillar is preferably one in which a band made of an elastic material such as urethane rubber is attached between two steel casters. The spline shaft protruding from the center of the machine body in the direction of the tube axis is hollow, and the work equipment (
It plays an important role in passing control cables and guide ropes for equipment such as traction and welding. The rotating cylinder attached to this spline shaft via a bearing is rotated around the spline shaft by a motor attached to the cylinder via a gear, and is also rotated via a gear by an electric motor attached to the main body of the device. Move in the direction of the tube axis. The air cylinder that moves the rotary grindstone forward and backward in the radial direction of the pipe is attached to the front end surface of the rotating cylinder attached to the spline shaft in the radial direction of the pipe via a slide rail, and the grinder is attached to the rod of this air cylinder. There is. The grinder is electric, and the inner surface of the tube is polished by a disc-shaped grindstone attached to an electric motor. Air is supplied from an air buffer tank attached to the rotating cylinder to the air cylinder that moves the grinder forward and backward in the radial direction of the pipe, and the pressure of the rotating grindstone is adjusted by adjusting the pressure inside the buffer tank. The reason why the pressure force of the rotary grindstone against the inner surface of the tube is controlled by the buffer tank is to prevent the rotary grindstone from getting caught in protrusions such as weld beads on the inner surface of the tube. That is, when grinding a protrusion such as a longitudinal bead or a circumferential bead in a pipe, when the grinder grindstone is bitten by the protrusion, the rotational torque rapidly increases. In order to prevent this, the present invention uses an air buffer to allow the grindstone to get over the protrusions. However, if the air cylinder operating pressure is low and the grinder operates in the reaction direction, the pressing force will be insufficient and the grinding performance will deteriorate. On the other hand, if the operating pressure is high, the contact force becomes strong, and unless the distance between the inner surface of the tube and the grinding wheel is minutely controlled, torque will be over, and the rotating grinding wheel will stop, making grinding impossible. Therefore, in order to prevent this, the operating pressure of the air cylinder must be controlled. Therefore, we connected the buff 7 tank to the air cylinder,
A method of controlling the operating pressure of the air cylinder was adopted so as to obtain a buff 1 that does not deteriorate its grinding performance even when the rotary grindstone collides with a protrusion. In addition, the adoption of an electric type grinder is due to the ease of maintenance and management.
This is because the cost can be reduced compared to an air grinder in terms of maintenance.

【Example】

FIG. 1 is a longitudinal sectional side view showing an example of the configuration of a towed tube inner surface polishing device according to the present invention, and FIG. 2 is a front view of the same device. (1) is a disc-shaped device main body, and a plurality of main body supporting caterpillars (2) for resiliently supporting the main body are attached to the outer peripheral end, and joints A and 8 are connected to a traction device (not shown). A spline shaft (3) having a spline shaft (3) is fixed to the center of the main body. The main body support caterpillar (2) is a side plate (2-3) to which two front and rear steel casters (2-2) are attached to a pair of left and right bearings (2-1) attached to the outer peripheral edge of the main body. The center part is supported at a point by a support shaft (2-4), and has a structure in which, for example, a urethane rubber band (2-6) is hung around steel casters. In other words, in this caterpillar, the urethane rubber band elastically contacts the inner surface of the tube, and the support shaft (
It has a structure that swings back and forth using 2-4) as a fulcrum. (4) is a rotating cylinder mounted on the spline shaft (3) so that it can move in the tube axis direction and can rotate around the spline shaft, and its structure allows it to move in the axial direction on the spline shaft (3). An inner cylinder (4-1) is fitted onto the outer cylinder, an intermediate cylinder (4-2) is attached to the inner cylinder, and a bearing (4-2) is attached to the intermediate cylinder.
-3) A gear mounted rotatably in the circumferential direction (
4-5) and an outer cylinder (4-4).
-4) has the same diameter as the main body (1), as shown in FIG. 2, and has a shape in which the top and bottom surfaces are cut out. A cover (4, -6) is integrally fixed to the intermediate cylinder (4-2), a motor (4-8) is attached to a plate member (4-7) protruding from this cover, and the gear (4-8) is driven by this motor. 4-9
) (4-5), the outer cylinder (4-4) rotates in the circumferential direction. In addition, the motor (4-10) installed in the device body (1)
The rod (4-
11) and another plate member (4-12) protruding from the cover (4-7). (5) is the air cylinder for operating the grinder,
It is fixed to a slide rail (5-1) attached to the front surface of the rotating cylinder (4) in the tube diameter direction. The lower end of the rod of this air cylinder (5) is connected to the slide rail (5-
1) is connected to a slide plate (5-2) that is movably fitted, and an electric motor (6) of the grinder is attached to this slide plate. (6-1) is a grindstone for polishing. Although an example in which two grinders are installed in parallel is shown here, it is needless to say that the grinders do not necessarily have to be of a double type, and that one grinder may be installed on each side. just,
In the case of a two-unit type, two units can be used at the same time to increase grinding efficiency, and one can be used as a paper whetstone and the other as a stone whetstone to polish rusted surfaces and grind uneven parts. When pre-treating the inner surface of a long-distance pipe, it is more efficient to prepare two types of abrasives. (7) is a buff 1 tank for supplying air to the air cylinder (5) for operating the grinder, and the rotary cylinder body (4)
It is installed integrally with the This buff 7 tank ('
7) is supplied with air (
or nitrogen gas) is supplied through a pressure hose and a solenoid valve (8). Further, the pressure inside the buffer 7 tank is adjusted by a regulator (pressure regulator). (9) is a light for illuminating the tube, (10 is a television camera, which is attached to the rotating cylinder (4). This is so that the grinding position and degree of grinding can be confirmed on a monitor outside the tube. (11) is a clamping device to prevent the device from moving in the tube axis direction during grinding, and is equipped with a caterpillar bearing (
2-1). When polishing the inside of the pipe with the above polishing device, while moving the polishing device using the traction device, check the polishing position with the TV camera (10), stop the device at a predetermined position, and fix it with the clamp device (moon). Grinding control is performed by controlling the pressure inside the buffer tank (with a regulator) to adjust the operating pressure of the air cylinder (5), that is, the contact pressure of the rotary grindstone (6-1) to the inner surface of the tube. For example, 15 mmφ x 200 mmr1. In the case of an air cylinder of ., a buffer of about 30 mm can be obtained at an operating pressure of about 3-4, so if a buffer tank of the same capacity is connected to the air cylinder, a buffer of about 60 mm can be obtained at an operating pressure of 3-4. Therefore, when supplying air to the polishing device from outside the pipe at a constant pressure of, for example, 7-4, the same pressure is supplied to one side to the clamp, and the other is supplied to the clamp at a constant pressure of 3-4 by the regulator.
It is sufficient to reduce the pressure to about -4, lead it to the buffer tank (7), and feed it to the air cylinder (5). This results in 6
Buff of about 0mm? is obtained, using a rotating grindstone (6-
Even if 1) collides with a protrusion inside the pipe, grinding can be carried out without any problem simply by controlling the pressure inside the buff 1 with a regulator. In addition, while the polishing equipment is running, the
m), if you come across a misaligned step, etc., if you use a general running roller, it will interfere with running and you may be unable to run, but in the case of caterpillar (2), the contact surface on the inner surface of the tube Since it is long in the direction of the tube axis, it runs smoothly without any problems. When grinding the weld bead on the inner circumferential surface of the pipe with a grinder, the motor (
By driving the gear (4-9) (4-8), the gear (4-9) (4
-5) to rotate the rotary cylinder (4). When moving the grinder in the tube axis direction, a motor (4-10) attached to the main body of the device is driven to move the rotary cylinder (4) on the spline shaft (3). [Effects of the Invention] As explained above, the present invention has the following effects. ■ By adopting a caterpillar system that has a single point support structure and uses a belt made of an elastic member as the running support means for the main body of the device, it is possible to prevent bends, cuts, dresser joints, etc. of pipes.
It is possible to run stably and smoothly on uneven steps, etc., without any problems. ■ An air cylinder is used as the operating means of the grinder, which has forward and backward movement and rotation functions, and the pressure contact of the grinder whetstone to the inner surface of the tube is controlled.By adopting a method that uses an arbor tank, the pressure contact of the grindstone is controlled. The force can be freely and easily adjusted using only a regulator, and grindability can be significantly improved. ■ By adopting an electric type for the grinder, there is no air pressure loss as with air grinders, and the air supply only requires an air cylinder to operate the grinder, allowing the diameter of the air hose to be reduced.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a configuration example of a tube inner surface polishing device according to the present invention, and FIG. 2 is a longitudinal sectional side view on the line I-(line), and FIG. 2 is a front view of the same device. 1... Disc plate Apparatus body 2...Body support caterpillar 3...Spline shaft 4...Rotating cylinder 5...Air cylinder 7...Air buffer tank 9...Light for lighting inside the tube 10...TV camera Applicant: Sumitomo Metal Industries, Ltd. Osaka Gas Co., Ltd.

Claims (1)

[Claims] A plurality of main body support caterpillars are provided on the outer peripheral end of the disc-shaped device main body having a diameter smaller than the inner diameter of the pipe so as to be in sliding contact with the inner surface of the pipe, and elastically support the main body, and the main body support caterpillars are provided protruding from the center of the main body in the direction of the pipe axis. A rotating cylindrical body fitted onto the spline shaft and driven forward and backward and rotationally by a motor is equipped with a rotating whetstone that is moved forward and backward in the radial direction of the tube by an air cylinder connected to an air buffer tank, and a light for imaging inside the tube. A towed pipe inner surface polishing device equipped with a television camera and a joint for towing the device.