JPS606433A - Method of joining pipe unit - Google Patents

Abstract

PURPOSE:To join joining sections perfectly, by closing an adhesive injecting section, and injecting an adhesive from adhesive injecting ports to exclude the air when a large diameter synthetic resin pipe is joined by the bell and spigot system. CONSTITUTION:A pipe unit 2 having adhesive injecting ports 7, 7' and air vents 8, 8' at the bell section 1 is arranged with the air vents' 8, 8' being at the highest position. Then after a spigot section 3 of another pipe unit 2 is inserted into the bell section 1 of the pipe unit 2, a corrosion-resistant layer is provided to cover the contacted sections of a spigot section lower surface 5 and the bell bottom section, and after a sealing layer 9 is provided throughout the circumferential contacted sections of the bell opening and the spigot section 3, an adhesive 4 is injected from the adhesive injecting ports 7, 7'. While the air is drawn from the air vents at the top of the closed section, the adhesive 4 is injected to completely fill the space.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for joining large-diameter synthetic resin pipes, particularly to a bell-and-spigot joining method.

[Prior art]

Traditionally, iron pipes or concrete pipes were used for large ducts to guide exhaust smoke to collective chimneys, etc., but in recent years, it has become necessary to remove BOX and NOx to prevent pollution. Desulfurization equipment and other equipment have been installed. When the removal method of 604 is a wet method, the exhaust gas outlet temperature of the flue gas desulfurization equipment is as low as 60 to 70C. Due to SOX, etc., these condensed water droplets are strongly acidic and tend to corrode the steel or concrete that is the material of conventional ducts.As a countermeasure against this corrosion, corrosion-resistant fiber-reinforced glass (hereinafter referred to as FRP) is used. abbreviated)
manufactured pipes began to be used.

The joining methods for FRP pigs include Chipal adhesive joining method, BU
There are various methods such as TT joining method, flange joining method, mechanical joint method, bell and spigot joining method, bell mouth taper joining method, etc., but the bell and spigot joining method is the best method for joining large diameter pipes. This method is the most suitable and has been adopted.

Figures 1 to 3 are schematic cross-sectional views showing a specific example of the conventional bell and spigot joining method. Figure 1 shows the state before joining, and Figures 2 and 5 show the state after joining. Indicates the condition.

Reference numeral 1 indicates a bell section, 2 indicates a pipe unit main body, 3 indicates a spigot section, 1' indicates a bell bottom, 5 indicates a lower end surface of the spigot section, 4 indicates an adhesive, and 6 indicates an inner layered section.

Conventionally, when building ducts to collective chimneys, etc., large diameter pipes had to be joined horizontally, but in this case -
The outer surface of the spigot section 6 of the pipe unit and the inner surface of the bell section 1 of the other pipe unit are sanded or blasted, or after applying adhesive resin putty to the inner surface of the bell section, the spigot section is It was inserted into the bell part, but even if the insertion clearance between the spigot part and the bell part was about 1% or more, the applied adhesive resin putty was pushed out, or the applied adhesive resin putty became uneven. Since the adhesive resin putty is not completely required, in many cases only about 10 to 15 pieces of the adhesive resin putty is effective when it is completely inserted.

For this reason, not only does gas leak from the joint, but also the cut surface of the glass fibers in FRP is often exposed at the lower end face 5 of the spigot part, so there is a tendency for corrosion to occur from this part. there were. In order to prevent this drawback, after joining the pipe units as described above, as shown in FIG.
It is also practiced to form a laminated part 6 made of FRP on the inner surface of the joint part of the pipe unit so as to cover the contact part with the pipe unit. In this case, in order to facilitate the formation of the laminated portion 6 made of FRP, the inner surface of the spigot portion 3 and the inner surface of the bell portion 1 are sanded or blasted in advance.

[Purpose of the invention]

This invention eliminates the drawbacks mentioned above,
The present invention provides a method for completely adhering a joint part to a design area, and also provides a method for rationalizing and reducing the cost of the joining method.

[Structure of the invention]

The present invention uses the bell and spigot joining method to
In the method of joining RP pipe units horizontally or in an inclined state with the pipe unit laid down, the pipe unit has an adhesive inlet and an air vent hole in the bell wall of the pipe unit, and the air vent hole is the highest. After installing the spigot part of the other pipe unit into the bell part, a corrosion-resistant laminated layer is applied to the inner surfaces of both pipe units so as to cover the contact area between the lower end surface 5 of the spigot part and the bottom part of the bell. After forming the sealing layer 9 (see Fig. 5) over the entire circumference of the contact area between the bell opening and the spigot part 3, apply adhesive from the adhesive injection port located at a lower position than the air vent hole. This is a method of joining FRP pipe units characterized by injection.

Next, the configuration of the present invention will be explained in more detail.

When directing exhaust smoke to a collective chimney, it is necessary to install a duct between the combustion furnace and the chimney. In this case, the duct must be installed horizontally or at an angle depending on the topography, but the present invention is particularly useful when installing such a duct by joining FRP pipe units.

In addition, to prevent corrosion inside the chimney, there is a method of joining and inserting an FRP nozzle unit, or a method of installing an FRP chimney itself.
Although it is often manufactured by joining RP and IIJ pipe units, the present invention is also useful in such cases where several pipe units are joined in advance.

The present invention will be explained based on the drawings.

Fig. 4 is a cross-sectional view of the part in which the spigot part of another pipe unit is inserted into the bell part of the - pipe unit according to the present invention, and Fig. 5 shows the lower end surface of the spigot part and the bell bottom part of the part shown in Fig. 4. 1 to 5.5 in the figure, a corrosion-resistant laminated layer is provided on the inner surface of the contact part to cover the contact part of
and 6 have the same meaning as in Fig. 5, 7 indicates the adhesive inlet, 8 indicates the air vent hole, 9 indicates the sealing layer (see Fig. 5), and 7' and 8' indicate the respective side implementations. The resin injection hole and the air vent hole in the embodiment are shown.

In the present invention, a pipe unit having an adhesive injection lower and an air vent hole 8 in the bell part of the pipe unit is arranged so that the air vent hole is at the highest position, and the spigot of another pipe unit is placed in the bell part 1. After inserting the spigot part, a corrosion-resistant layer 6 is provided to cover the contact area between the spigot lower end face 5 and the bell bottom part 1, and a sealing layer 9 is provided over the entire circumference of the outer periphery contact area between the bell opening and the spigot part 3. After press-fitting the adhesive through the adhesive injection lower and completely filling the space between the inner wall of the bell section and the outer wall of the spigot section with the adhesive, the pipe unit is made stronger by completely curing the adhesive. Can be joined.

In addition, in the embodiment shown in FIGS. 4 and 5,
The air vent hole 8 and the adhesive inlet are provided in the bell part of the sleeve unit so that the air vent hole 8 is at the highest position and the adhesive injection lower is at the lowest position. It only needs to be located below the hole 8, and does not need to be provided at the lowest position. Also, when installing the nokuib in an inclined position, for example, when installing the nokuib in a position where the left side is higher as shown in Figure 5, an air vent hole should be provided at position 8' near the bell opening. Moreover, the adhesive injection port may be provided at a lower position, for example, at a position 7'. The size of the resin injection port is preferably the same size as the outer diameter of the resin injection nozzle, and the size of the air vent hole may be any size, but it may be about the same size as the diameter of the resin injection port. It is preferable to make it somewhat larger. Further, the shape of the air vent hole may be any shape, and the number of air vent holes may be not just one but a plurality of holes.

The corrosion-resistant layer 6 can be obtained, for example, by impregnating string-like glass wool cloth with an adhesive, laminating it in several layers, and curing the adhesive. The sealing layer 9 is provided for the purpose of preventing the adhesive from leaking when injecting the adhesive, so it is sufficient to use resin putty, but if this alone is insufficient, use a glass coat after laminating the resin putty. 1 to 2 layers (8') of mats, etc. may be used.

The adhesive to be used is preferably one made of unsaturated resin of the same weight as the resin used in manufacturing the pipe unit, such as unsaturated polyester resin adhesive or epoxy resin adhesive, and for ease of injection. The viscosity is preferably 0.5 to 5 voids.

In order to improve the adhesion between the bell part and the spigot part or the adhesion of the corrosion-resistant layer 6, before inserting the spigot part into the bell part, the outer surface of the spigot part, the inner surface of the bell part, the inner surface of the spigot part, and the inner inner surface of the bell part are coated. It is preferable to roughen the surface by sanding or plastic processing.

〔Example〕

A pipe unit made of glass fiber reinforced polyester resin with a diameter of 120 crn, a thickness of lon, a length of IOm, and a length of the bell part of 10 crn.
A pipe unit with a 5 m resin injection port and an air vent hole with a diameter of 2 tyn at a position opposite to the hole in the diameter direction of the pipe is arranged horizontally, and the bell part of the pipe unit is equipped with another cylinder body. The spigot part was inserted. The distance between the inner surface of the bell portion and the outer surface of the spigot portion was 4 m.

Next, a string-like glass fiber cloth with a width of 10 tM is impregnated with an unsaturated polyester adhesive (trade name Ripoxy R-802, manufactured by Showa Kobunshi Co., Ltd. λ) so as to cover the contact area between the lower end surface 5 of the spigot and the bottom of the bell. A corrosion-resistant layer 6 was formed by laminating three layers on the inner surfaces of the contact areas of both cylinders.Next, a resin was applied to the entire circumference of the bell opening and the outer contact area of the spigot. After the corrosion-resistant layer and resin putty have hardened, an unsaturated polyester adhesive with a viscosity of 4 voids (trade name Ripoxy R-802, manufactured by Showa Kobunshi Co., Ltd.) is inserted from the resin injection port. Company H) was press-fitted at a rate of 5k19/min. Approximately 2
When the adhesive came out from the air vent hole after several minutes, the injection was stopped and the adhesive was left to harden. It can be seen from the amount of adhesive injected that the space between the bell section and the spigot section was almost completely filled with the adhesive.

(Effects of the Invention) In the present invention, after the adhesive injection part is sealed, the adhesive is injected from the adhesive injection port while removing air from the air vent hole in the upper part of the sealed part according to the amount of adhesive injected. Therefore, the space in which the adhesive is to be applied can be completely filled with the adhesive, and the adhesive can be bonded more completely than in the conventional method.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional views of two pipes to explain the conventional method of joining pipe units; Figure 4;
FIG. 5 shows a partial sectional view of two pipes for explaining the method of the invention. 1. Bell part, 2. Pipe unit, 3. Spigot part, 4. Adhesive, 5. Lower end surface of spigot part, 6
・・Inner surface layer part, 7.7・・Adhesive injection port, 8.8′・
・Air vent hole, 9...Sealing layer Applicant Fuji Kako Co., Ltd. Agent Hirodo Nakamoto Shodo Inoue Katsura Yoshimine Figure 1-1 Figure 5

Claims (1)

[Claims] 1. In the method of joining multiple pipe units horizontally or in an inclined state using the bell and spigot method, a pipe unit with an adhesive inlet and an air vent hole in the bell part is placed at the highest position of the air vent hole. After inserting the spigot part of another pipe unit into the bell part of the pipe unit, a corrosion-resistant layer is provided to cover the contact part between the lower end surface of the spigot and the bottom part of the bell, and a corrosion-resistant layer is provided to cover the contact part between the bell opening and the spigot part. A method for joining pipe units, which comprises: providing a sealing layer over the entire circumference of the outer circumferential contact area with the pipe unit, and then press-fitting an adhesive through an adhesive injection port.