JPH0512603Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention relates to a connection structure for refractory lined tubes for connecting the refractory lined tubes at one end thereof.

(Prior Art) For example, the flue of a boiler is constructed by connecting a plurality of pipe bodies with refractory linings. These refractory lined tubes are made by forming an impermeable corrosion-resistant film such as epoxy resin or asphalt on the inner peripheral surface of a steel tube, and then forming a refractory lining such as a monolithic refractory on top of that. The end face of the refractory lining was exposed at its end.

Conventionally, the connection structure of such a pipe body with a refractory lining is such that, for example, the two pipe bodies are brought into a butt state and a gasket is sandwiched between the end faces of the refractory lining, and in this state, a flange portion provided at the end of both the pipe bodies is It was common to tighten the bolts with bolts.

(Problem to be solved by the invention) However, with the above configuration, the exposed end face of the refractory lining is directly affected by the strong tightening force of the bolts and the impact force caused by the vibration of the tube, which makes the refractory lining relatively brittle. There is a problem in that the lining is easily damaged and chipped. Moreover, since the sealing gasket is applied to the end face of the refractory lining which does not have sufficient smoothness, there is a drawback that the adhesiveness between the gasket and the end face of the refractory lining is insufficient and gas leaks are likely to occur. be. Furthermore, if an impermeable corrosion-resistant film is formed on the inner surface of the pipe, it will be in direct contact with the packing, so vibrations of the pipe will cause the impermeable corrosion-resistant film to be rubbed. There was also the problem that they would tear and gradually lose their corrosion resistance.

Therefore, the purpose of the present invention is to prevent damage to the refractory lining, maintain sufficient sealing performance, and prevent damage when an impermeable corrosion-resistant film is formed on the inner peripheral surface of the pipe. To provide a joint structure of a pipe body with a fireproof lining that can prevent the above-mentioned problems.

[Structure of the invention] (Means for solving the problem) The connection structure of the pipe body with refractory lining according to the present invention includes a flat annular plate covering the end face of the refractory lining and an inner circumferential surface of the end of the refractory lining. A reinforcing metal fitting with an L-shaped cross section that integrally has a short cylindrical part that is attached to the
It is characterized by a structure integrated with the pipe body (Claim 1
invention).

In addition, when an impermeable corrosion-resistant film is formed on the inner circumferential surface of the tube, the impermeable corrosion-resistant coating applied to the inner circumferential surface of the tube is continuous at least on the annular plate portion of the reinforcing metal fittings. It may also be in a formed form (device of claim 2).

(Function) Since the end face of the refractory lining is covered by the annular plate of the reinforcing metal fitting, the impact force due to the clamping force and vibration at the connecting part of the pipe body is not applied to the end face of the refractory lining but to the annular plate. However, it is not as strong as the refractory lining. Moreover, since the inner circumferential surface of the end portion of the refractory lining is covered with the short cylindrical portion of the reinforcing metal fitting, the refractory lining is suspended, especially at the upper part, so that peeling of the refractory lining can be reliably prevented.
Moreover, since the flat annular plate portion can be used for sealing, the adhesiveness with the sealing parts is improved, and excellent sealing performance can be obtained.

Furthermore, when an impermeable corrosion-resistant film is formed on the inner peripheral surface of the tube, by forming the impermeable corrosion-resistant film in series on the annular plate part, the impermeable corrosion-resistant film can also be formed. It can now be protected by the reinforcing member, and its tearing etc. can be prevented.

(Example) Hereinafter, a first example in which the present invention is applied to a connection structure of a refractory lined pipe constituting a flue of a boiler will be described with reference to FIG. 1.

1 is a cylindrical steel tube, 2 is a flange portion provided by welding on the outer periphery of the connecting end thereof, and 3 is a plurality of connecting holes formed in this flange portion 2. As shown in FIG. An impermeable corrosion-resistant film 4 such as epoxy resin or asphalt is continuously formed on the inner peripheral surface of the tube 1 on the side of the flange portion 2 and on the end surface of the flange portion 2, spanning both sides. A similar impermeable corrosion-resistant membrane 5 is formed over the entire inner peripheral surface of the tubular body 1.

Reference numeral 6 denotes a refractory lining formed by spraying a monolithic refractory, for example, and is formed in a cylindrical shape over the entire inner circumferential surface of the tube body 1, overlapping the impermeable corrosion-resistant film 5. Incidentally, the thickness dimensions of the impermeable corrosion-resistant film 5 and the refractory lining 6 are, for example, 3 mm for the former and 50 mm for the latter when the diameter of the tubular body 1 is approximately 5.8 m. Reference numeral 7 denotes a reinforcing metal fitting made of a material with excellent corrosion resistance and heat resistance.This metal fitting has an L-shaped cross section by integrating a short cylindrical part 9 on the inner peripheral side of a flat annular plate part 8 by welding. Further, the impermeable corrosion-resistant film 5 described above is formed in a continuous manner from the inner circumferential surface of the pipe body 1 to the annular plate portion 8 of the reinforcing metal fitting 7. Therefore, the impermeable corrosion-resistant film is formed at the connecting side end of the pipe body 1. There are two layers on the inner periphery. 10 is an expansion bellows provided between the tube body (not shown), and 11 is a destination plate. The reinforcing metal fitting 7 has an annular plate portion 8 whose inner peripheral side covers the end face of the fireproof lining 6, and a short cylindrical portion 9 which covers the fireproof lining 6.
The flange portion 10a of the expansion bellows 10 and the destination plate 11 are placed on top of the expansion bellows 10 and are tightened with bolts 12. As a result, the reinforcing metal fitting 7 and the expansion bellows 10 are fixed to the tube body 1. Incidentally, reference numeral 13 designates a number of anchors protruding from the inner circumferential surface of the tube body 1 in order to improve the adhesion of the refractory lining 6.

With the above configuration, the end face portion of the fireproof lining 6 is covered and protected by the annular plate portion 8 of the reinforcing metal fitting 7, so that, for example, even if the bolt 12 is strongly tightened to increase the connection strength, too,
Flange portion 10 of expansion bellows 10
a etc. are not directly pressed against the end face portion of the refractory lining 6. Furthermore, even if the pipe body 1 vibrates, the flange portion 10a of the expansion bellows 10 is not the end face portion of the refractory lining 6;
This will collide with the annular plate portion 8 of the reinforcing metal fitting 7.
Therefore, it is possible to reliably prevent the end face portion of the refractory lining 6 from being damaged by the tightening force from the bolt 12 or impact caused by vibration, and to prevent the occurrence of chipping or cracking. . Moreover,
The inner circumferential surface of the end of the refractory lining 6 is covered by the short cylindrical portion 9 of the reinforcing metal fitting 7, so that the refractory lining 6 is suspended, especially at the upper part, so that the refractory lining 6 is prevented from being damaged and falling off. This can be reliably prevented from occurring. Furthermore, since the flange portion 10a of the expansion bellows 10 comes into close contact with the flat annular plate portion 8 rather than with the refractory lining 6, which lacks smoothness, the sealing performance is greatly improved compared to the conventional one. In addition, since the impermeable corrosion-resistant film 5 is formed in a continuous manner from the inner peripheral surface of the pipe body 1 to the annular plate portion 8 of the reinforcing metal fitting 7, it is possible to protect the impermeable corrosion-resistant film 5, and Corrosive liquid is reliably prevented from penetrating into the gap between the plate part 8 and the pipe body 1,
Corrosion resistance can also be improved.

Next, a second embodiment of the present invention will be described with reference to FIG. This embodiment differs from the first embodiment in that the two tube bodies 1, 1 are directly butt-connected without using an expansion bellows, and the other points are the same as in the first embodiment. The structure is similar to that of the embodiment. In the same figure, 1
4 is a ring-shaped gasket, which is attached to both tube bodies 1.
It is arranged so as to be sandwiched between the annular plate parts 8, 8 of the reinforcing metal fitting 7, and is tightened and fixed with bolts 12.

Even with this configuration, like the above embodiment,
Since the end face portion of the refractory lining 6 can be prevented from being damaged by the impact caused by the tightening force from the bolts 12 or vibrations, it is possible to reliably prevent chipping, cracking, or peeling of the refractory lining 6. Also,
Since the packing 14 comes into close contact with the flat annular plate portion 8, the sealing performance is greatly improved, and the impermeable corrosion-resistant film 5 also improves the corrosion resistance.

In each of the above embodiments, an impermeable corrosion-resistant film is formed on the inner peripheral surface of the pipe body 1, but the present invention can also be applied to cases where this impermeable corrosion-resistant film is not necessarily formed. Needless to say, it is possible to obtain effects such as preventing damage to the fireproof lining and improving sealing performance. Further, in each of the above embodiments, the reinforcing metal fittings are fastened to the tube body using bolts, but in cases where there is a lot of vibration, the reinforcing metal fittings may be integrated with the tube body by welding.
In addition, the size and shape of the tube body of the present invention is not limited to those of the above-mentioned embodiments, and various modifications can be made without departing from the scope of the invention.

[Effects of the invention] As described above, according to the structure of the invention, the end face portion and the inner circumferential surface of the end portion of the fireproof lining are covered by the annular plate portion and the short cylindrical portion of the reinforcing metal fitting.
To be able to prevent the impact force caused by the clamping force and vibration at the connecting part of the pipe body from reaching the refractory lining and causing it to damage or fall off, and to obtain excellent sealing performance by using the flat annular plate part. I can do it.

In addition, when an impermeable corrosion-resistant film is formed on the inner peripheral surface of the pipe body, if the impermeable corrosion-resistant film is formed in series on the annular plate, the impermeable corrosion-resistant film is also reinforced. This allows the member to be protected, prevents it from breaking, and improves corrosion resistance.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part showing a first embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of a main part showing a second embodiment of the present invention. In the drawing, 1 is a pipe body, 4 and 5 are impermeable corrosion-resistant membranes,
6 is a fireproof lining, 7 is a reinforcing metal fitting, 8 is an annular plate portion, 9 is a short tube portion, 10 is an expansion bellows, and 14 is a packing.

Claims (1)

[Claims for Utility Model Registration] 1. A structure for connecting pipes with refractory lining provided on the inner circumferential surface of the pipes at one end thereof, the structure comprising a flat pipe covering the end face of the refractory lining. A connection of a tube body with a refractory lining, characterized in that a reinforcing metal fitting having an L-shaped cross section and integrally having an annular plate portion and a short tube portion facing the inner circumferential surface of the end portion of the refractory lining is integrated into the tube body. Departmental structure. 2. The pipe body with a refractory lining according to claim 1, wherein at least the annular plate portion of the reinforcing metal fitting is formed with a series of impermeable corrosion-resistant films applied to the inner circumferential surface of the pipe body. connection structure.