JPH07164445A - Lining peeling method - Google Patents

Abstract

PURPOSE:To separate and recover a lining material and a steel tube by cooling a lining steel tube to an embrittle temperature or lower, and applying an impact to peel the lining material from the tube. CONSTITUTION:A lining steel tube 1 is introduced into a cooling tank 2 and cooled to an embrittle temperature or lower. The cooled tube 1 is taken out from the tank 2, both the tube 6 and a lining material 7 are crushed by an impact of a hitting unit 5 such as a hammer, etc., and separated from one another to become small pieces. In this case, an indoor temperature measuring thermometer 4 is provided in the tank 2, a refrigerant supply amount is controlled by a temperature regulator 3 in response to a measured temperature output from the thermometer 4, its temperature is regulated to an optimum cooling temperature of the material 7, to be at the embrittle temperature or lower, and they are crushed and separated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to waste treatment,
TECHNICAL FIELD The present invention relates to a separation technique for separately collecting metal and plastic, and more particularly to a lining peeling method for separating a lining material from a steel pipe member made of metal and a lining steel pipe provided with a plastic lining material on its surface.

[0002]

2. Description of the Related Art In a lining steel pipe used as a gas pipe, a resin such as plastic is coated as a lining material on the surface of the steel pipe to prevent corrosion. If you try to peel the lining material from the waste lining steel pipe and run it with a crusher at room temperature, the lining will deteriorate due to the heat generated when the steel pipe part is crushed, or it will be fused to the crushed pieces of the steel pipe The subsequent separation of the steel pipe and the lining material cannot be performed well. A technique for crushing and separating two kinds of metals, iron and copper, by utilizing low-temperature brittleness is described in Japanese Patent Publication No. 59-12354, but crushing and separating between iron and plastic is completely absent. Not touched.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a plastic lining peeling method capable of favorably separating a steel pipe and a lining material.

Another object of the present invention is to crush into small pieces of a size that can be separated by simple magnetic sorting and the like.
Another object of the present invention is to provide a plastic lining peeling method capable of separating a steel pipe and a lining material.

Further, another object of the present invention is to provide a plastic lining peeling method capable of separating a steel pipe and a lining material with smaller impact energy and cooling energy.

[0006]

In order to achieve the above object, the present invention is provided with a step of cooling the lining steel pipe to a temperature not higher than the brittle temperature of the material and then applying an impact.

The impact force applied to the lining steel pipe is preferably selected so as to crush only the lining material without crushing the steel pipe which is the mother pipe.

Further, the cooling temperature causes brittle fracture in each case such as crushing the steel pipe, crushing only the lining material without crushing the steel pipe, and different kinds of lining materials of the lining steel pipe. It is desirable to be able to adjust the cooling temperature so that the temperature is suitable for.

[0009]

In the peeling method according to the present invention, since the lining steel pipe is cooled to the embrittlement temperature or lower, the lining steel pipe is crushed by a simple impact load, and as a result, the lining material can be peeled from the steel pipe.

Further, by adjusting the impact load to the extent that the mother tube is not crushed, the lining material can be peeled off with a smaller impact force.

Also, by adjusting the cooling temperature according to various cases, an appropriate cooling temperature can be given in each case, so that the lining steel pipe can be prevented from being overcooled and the cooling energy can be saved. .

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. Figure 1
FIG. 3 is a schematic system diagram showing an embodiment of a lining peeling method according to the present invention.

The lining steel pipe 1 is put into a cooling tank 2 and cooled to a predetermined temperature. Cooled lining steel pipe 1
Is taken out of the cooling tank 2 and impacted on the lining steel pipe 1 by a hammer (hammer) 5. The steel pipe 6 and the lining material 7 constituting the lining steel pipe 1 are crushed together by the impact of the impacting machine 5, and become small pieces separated from each other. The cooling tank 2 is provided with a thermometer 4 for measuring the temperature inside the tank, and the temperature controller 3 controls the amount of refrigerant supplied to the cooling tank 2 according to the temperature measurement output from the thermometer 4. By this control, the temperature of the cooling tank 2 is adjusted so as to reach the optimum cooling temperature of the lining material 7. When the lining material 7 is formed of, for example, polyvinyl chloride, the embrittlement temperature is about −20 ° C. to −30 ° C. Therefore, the temperature in the cooling tank 2 is about −30 ° C. to −40 ° C. If it is made of polyethylene, the embrittlement temperature is about -60 ° C to -70 ° C, so the temperature in the cooling tank 2 is selected to be about -70 ° C to -80 ° C. Is preferable from the viewpoint of energy efficiency. Further, in order to use the difference in the coefficient of thermal expansion between the steel pipe 6 and the lining material 7 so that a large stress is generated in the lining material 7 so that the lining material 7 is easily crushed, the lower the temperature in the cooling tank 2, the better,
It is preferable to select about 00 ° C to -150 ° C.

Next, FIG. 2 shows another method as a load applying method for peeling the lining material. The lining steel pipe 1 cooled to a predetermined temperature is strongly pressed against the gap between the rollers 101 and 102 provided so as to sandwich the lining steel pipe 1 and is passed from the left side to the right side in the figure. As a result, the lining steel pipe 1 is deformed. Further, even if the lining steel pipe 1 is not deformed, a concentrated load is applied to a portion where the lining material 7 and the rollers 101 and 102 are in contact with each other. As a result, the lining material 7, which is brittle due to cooling, is easily crushed and separated from the steel pipe 6.

The force for pressing the rollers 101 and 102 against the lining steel pipe 1 at this time is preferably selected so as not to crush the steel pipe 6 itself.

FIG. 3 shows another example of the load applying method for peeling the lining material. The lining steel pipe 1 cooled to a predetermined temperature is put into a peeling machine 201 having protrusions 202 inside. The peeling machine 201 includes a spring 204 and a damper.
It is supported by 205 and is vibrated by an exciter 203. Due to this vibration, the peeling machine 201 and the lining steel pipe 1 in the main body vibrate and jump, and as a result, the lining steel pipe 1 collides with the projection 202 and the lining material 7 is crushed and peeled from the steel pipe 6.

FIG. 4 shows still another example of the load applying method for peeling the lining material. By launching a small steel ball 302 onto the surface of the lining steel pipe 1 cooled to a predetermined temperature by a launching device 301 that continuously launches at high speed, the lining material 7 embrittled by cooling is easily crushed. The steel pipe 6 is peeled off.

[0018]

As described above, according to the present invention, the lining steel pipe 1 can be easily crushed by cooling the lining steel pipe 1 to the embrittlement temperature or lower.
Can be easily separated from the steel pipe 6.

Further, the crushing energy can be reduced by applying an impact force to the extent that the steel pipe main pipe is not crushed. Further, in the case where only the lining material 7 is crushed without crushing the mother pipe, or when the type of the lining material 7 of the lining steel pipe 1 is different, the cooling temperature is set so as to be a temperature suitable for brittle fracture of the material. By adjusting, cooling energy can be saved.

[Brief description of drawings]

FIG. 1 is a schematic system diagram showing an embodiment of a lining peeling method according to the present invention.

FIG. 2 is a conceptual diagram showing an example of a method for applying a load to a lining steel pipe by using rollers.

FIG. 3 is a conceptual diagram showing an example of a lining peeling method by vibration.

FIG. 4 is a conceptual diagram showing an example of a lining peeling method by continuous collision of steel balls.

[Explanation of symbols]

1 ... Lining steel pipe, 2 ... Cooling tank, 3 ... Temperature controller, 4
… Thermometer, 5… Impactor, 6… Steel pipe, 7… Lining material,
101, 102 ... Rollers sandwiching a lining steel pipe, 20
1 ... Peeling machine, 202 ... Protrusion, 203 ... Exciter, 204 ...
Spring, 205 ... Attenuator, 301 ... Steel ball launching device, 302
…wrecking ball.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroaki Kobayashi, Hiroaki Kobayashi 794, Higashitoyoi, Kudamatsu City, Yamaguchi Prefecture, Ltd. Inside the Kasado Plant, Hitachi, Ltd. (72) Takao Okuma 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. (72) Inventor Kyoji Tomita 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. (72) Inventor Yuichi Oki 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. In the company

Claims (6)

[Claims] 1. A step of cooling a steel pipe member and a lining steel pipe provided with a lining material on its surface to a temperature lower than its embrittlement temperature, and an impact is applied to the cooled lining steel pipe to remove the lining material from the steel pipe member. A lining peeling method, which comprises a peeling step. 2. The impact applied to the lining steel pipe is given by applying a force to the lining steel pipe, which is large enough to crush the lining material without crushing the steel pipe member. Lining peeling method. 3. The lining peeling according to claim 2, wherein the impact applied to the lining steel pipe is given by sandwiching the lining steel pipe with one or more sets of rollers which face each other across the lining steel pipe. Method. 4. The impact applied to the lining steel pipe is provided by placing the lining steel pipe in a box having a plurality of projections inside and vibrating the box itself. 2. The lining peeling method described in 2. 5. The impact applied to the lining steel pipe is provided by continuously colliding the steel balls having a diameter smaller than the pipe diameter with the lining steel pipe at a high speed. Lining peeling method. 6. The lining peeling method according to claim 1, wherein a temperature for cooling the lining steel pipe is a temperature slightly lower than an embrittlement start temperature determined by a material of the lining material.