JP2001252617A - Rust preventive lining method on pipe inner surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a lining layer uniform and smooth in the circumferential direction in the case of forming the lining layer having a filler added in the resin layer on the inner surface of a metallic pipe as a rust preventive lining layer. SOLUTION: The lining layer is formed by supplying a rust preventive lining resin to the inner surface of the metallic pipe 3 rotatably supported around the shaft and uniformly dispersing into the inner surface of the metallic pipe 3 by centrifugal force, the filler 4 for the lining resin is uniformly spread in the circumferential direction by spreading the filler from the tip of a trough 2 inserted into the metallic pipe 3 radially with the trough 2 used as an axis and at the same time, the trough 2 is moved toward the axial direction of the metallic pipe 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anticorrosion lining method for an inner surface of a pipe.

[0002]

2. Description of the Related Art A metal pipe such as a ductile cast iron pipe is subjected to an inner lining treatment with a material made of a material having excellent chemical resistance and excellent physical strength from the viewpoint of inner corrosion protection.

As such excellent lining materials, for example, resins such as unsaturated polyester resins are known. In the meantime, the following method has conventionally been used to perform corrosion-resistant lining on the inner surface of a tube with a resin such as these unsaturated polyester resins.

That is, a target tube is rotatably supported, a liquid resin is supplied into the rotating tube, and the resin is diffused along the inner peripheral surface of the tube by centrifugal force to form a uniform resin layer. For example, a filler such as sand is scattered and supplied to the resin layer, and the resin layer is submerged in the resin layer using centrifugal force, and then the resin is cured.

In the above process, when the filler is sprayed, a spiral feeder 1 is provided in a metal tube 3 which is horizontally supported by rollers 7 and 7 and is rotated around an axis as shown in FIG. The trough 2 is inserted, and the support cart 8 of the trough 2 is moved at a constant speed in the direction of the arrow A while the filler 4 such as silica sand is dropped and supplied from the opening of the tip 2 a to move the metal tube 3 relative to the rotation direction. As a result, the filler 4 was uniformly dispersed over the entire inner surface of the pipe.

[0006]

However, since the supply of the filler 4 from the tip of the trough 2 is performed by spontaneous fall, the amount of the scattered material in the metal pipe 3 is reduced due to the pulsation of the spiral feeder 1 and the like. It is hard to be uniform in the circumferential direction, so the mixing ratio of resin and filler is not constant along the circumferential direction,
There was a problem that it was difficult to form a uniform and smooth lining.

Further, the metal tube 3 is made of, for example, GNo. When rotated at a high speed of 10 or more, the filler 4 flows and disperses along the inner surface of the pipe due to a large centrifugal force. In this case, if the metal pipe 3 itself is eccentric, the eccentricity causes the lining layer thickness to be reduced. This causes problems such as uneven wall thickness and separation of additives mixed with the resin.

[0008] The present invention solves the above-mentioned problems, and when adding and dispersing a filler to the lining layer, the filler is uniformly dispersed in the circumferential direction without causing adverse effects such as uneven thickness and separation of the additive in the lining resin layer. Therefore, it has been made to provide a uniform and smooth lining layer.

[0009]

According to the method of the present invention, a corrosion-resistant lining method for a pipe inner surface is provided in which a corrosion-resistant lining resin is supplied to an inner surface of a metal tube rotatably supported around an axis, and the resin is uniformly dispersed on the inner surface of the metal tube by centrifugal force. In the corrosion-resistant lining method in which a lining layer is formed and then a filler is supplied and settled in the lining layer, the filler is dispersed and supplied after the lining layer is formed. Are spread radially so as to be uniformly distributed in the circumferential direction of the inner surface of the metal tube, and at the same time, the trough is moved in the axial direction of the metal tube.

Therefore, according to the present invention, after the lining layer is formed by the resin, the filler such as silica sand is radiated from the tip of the trough in a radial manner. It is a smooth lining resin layer.

Further, it is not necessary to rotate the pipe at a high speed in order to uniformly disperse the filler in the lining layer, and the problem of uneven thickness of the lining resin and separation of additives due to the high speed rotation is eliminated.

[0012]

Next, an embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing an embodiment in which a filler is sprayed in the method for corrosion-resistant lining of a pipe inner surface according to the present invention, FIG. 2 is an enlarged cross-sectional view of a trough tip portion in FIG. 1, and FIG. It is.

In FIG. 1, reference numeral 5 denotes a tube rotation supporting device. The pipe rotation supporting device 5 is constituted by disposing rolls 7... 7 for supporting a metal pipe 3 such as a ductile cast iron pipe from a pipe outer surface on a base 6 in a horizontal posture along the axial direction of the metal pipe. One of these rolls 7 is a drive roll.

First, a metal pipe 3 such as a ductile cast iron pipe is placed horizontally on the pipe rotation supporting device 5, and a driving roll 7 is driven to rotate the metal pipe 3. Although not shown, a lining material such as a liquid unsaturated polyester resin is supplied into the rotating metal tube 3 by a resin supply device, and is dispersed in a layered manner on the inner surface of the tube by centrifugal force.

The number of rotations of the pipe when supplying the lining material may be such that the lining material is uniformly dispersed on the inner surface of the pipe, and the uneven thickness of the lining layer due to the eccentricity of the metal pipe 3. It is not necessary to produce high-speed rotation such that the additive material added to the lining material is separated by centrifugal force.

When the supply of the lining material is completed in this way, before the resin, which is the lining material, is cured, the filling material supply device is connected to the metal pipe 3 as shown in FIG.
Inserted into

This filler supply device is provided on a support carriage 8 and has a trough 2 having a spiral feeder 1 and a metal pipe 3.
Is disposed at an extended position of the metal tube 3 from the tube end 3b, and can reciprocate in the tube extending direction.

At the end of the trough 2 is provided a cone-shaped guide member 2a for guiding the filler 4 such as silica sand sent radially outward as shown in FIG. Are provided with window holes 2b... 2b through which the filler material 4 passes, and an impeller 2e having a plurality of radially provided blades 2d. In the figure, reference numeral 2f denotes a rotating shaft of the impeller 2e, which penetrates through the shaft 1a of the spiral feeder 1 and is connected to a driving device (not shown) installed on the carriage 8.

Then, before the lining resin is hardened, the support cart 8 is moved so that the end of the trough 2 is
At the same time, the spiral feeder 1 is operated, and at the same time, the impeller 2e is rotated at a high speed to feed the filler 4 to the tip of the trough 2 and move backward as indicated by the arrow A.

The filler 4 is guided from the tip of the trough 2 by the cone-shaped guide member 2a and is pushed out to the outside, and is impeller 2e.
The blades 2d... 2d are radially bounced off and radially spread over the entire circumferential direction.

Accordingly, the filler 4 moves along the axial direction of the metal tube 3 while being scattered radially from the tip of the trough 2 around the trough 2 while the metal tube 3 continues to rotate. Numerals 4 are uniformly distributed in the entire circumferential direction on the inner surface of the metal tube 3.

The uniformly dispersed filler 4 sinks into the lining resin layer by centrifugal force. in this way,
The filler is uniformly distributed in the lining layer, and a uniform and smooth lining layer is formed. Example A ductile cast iron pipe 3 was horizontally supported by a pipe rotation support device 5 and GNo. 0.5 to GNo. The tube was rotated at a low speed of about 10 to supply a liquid unsaturated polyester resin into the ductile cast iron tube 3 and uniformly diffused the inner surface of the tube by centrifugal force to form a lining resin layer.

The trough 2 is inserted to the innermost part of the ductile cast iron tube 3 rotating before the resin layer is hardened, and the filler 4 sent by the spiral feeder 1 is extruded from the tip of the trough 2 and extruded. Filler 4 is supplied at a peripheral speed of 0.1 m / sec.
Spraying was performed by radially scattering from the tip of the trough 2 with an impeller 2e rotating at a high speed of about 20 m / sec.

At the same time, the support cart 8 was retracted, and the filler 4 was sprayed uniformly on the inner surface of the ductile cast iron pipe 3. After checking the lining layer on the inner surface of the pipe after the resin has hardened,
All of the filler was in a state of being settled at the bottom of the resin layer at a constant spray amount at all points in the pipe, and a uniform and smooth lining layer was formed.

[0025]

As described above, according to the corrosion-resistant lining method for the inner surface of the pipe according to the present invention, the filler of the lining resin supplied to the inner surface of the pipe is radially supplied from the tip of the trough to the entire periphery. Even if the number of rotations of the tube is not high, it is constant at all points in the tube, and a uniform and smooth lining layer can be formed without separation of the resin hardener.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a supply state of a filler in a method for corrosion-resistant lining of a pipe inner surface.

FIG. 2 is an enlarged sectional view of a main part of an apparatus for supplying a filler in a method for corrosion-resistant lining of a pipe inner surface.

FIG. 3 is a sectional view taken along line XX of FIG. 2;

FIG. 4 is an explanatory sectional view of a conventional method.

[Explanation of symbols]

 Reference Signs List 1 spiral feeder 2 trough 2e impeller 3 metal pipe such as ductile cast iron pipe 3b pipe end of metal pipe 4 filler 5 pipe rotation support device 6 base 7 roll 8 support trolley

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16L 58/10 F16L 58/10 // B05C 11/08 B05C 11/08 F term (Reference) 3H024 EA01 EC02 ED06 EE03 4D075 AC19 AC64 CA33 DA15 DB01 EC13 4F042 AA03 DF32 EB00

Claims (1)

[Claims] An anticorrosive lining resin is supplied to an inner surface of a metal tube which is rotatably supported around an axis, and is uniformly dispersed on the inner surface of the metal tube by centrifugal force to form a lining layer. Then, a filler is added to the lining layer. In the anticorrosion lining method of supplying and sinking, in dispersing and supplying the filler after forming the lining layer, the filler is radially sprayed from the tip of the trough inserted into the metal pipe to thereby circumferentially surround the inner surface of the metal pipe. A corrosion-resistant lining method for the inner surface of the metal pipe, wherein the metal pipe is uniformly sprayed and the trough is simultaneously moved in the axial direction of the metal pipe.