KR20120017105A

KR20120017105A - Pipe connecting method using liner

Info

Publication number: KR20120017105A
Application number: KR1020100079582A
Authority: KR
Inventors: 정태화
Original assignee: 정태화
Priority date: 2010-08-18
Filing date: 2010-08-18
Publication date: 2012-02-28

Abstract

A method of jointing a resin-lined pipe, consisting of first joining the liners of two pipes to be jointed together and then assembling the joints to fit the pipes.

Description

Pipe Connecting Method Using Liner

The present invention relates to a jointing method which prevents leakage at the joint in the joint of the pipe and prevents fluid from directly contacting the pipe or the joint, and a joint structure suitable for such jointing.

In order to prevent corrosion of the pipe and improve other functions, technologies for painting, coating and lining the pipe with various materials have been developed. Especially, polyethylene, polyflopropylene, PVC, and fluorine resin, which are excellent chemical and abrasion resistant materials, have been developed. Many lining tubes using resins have been developed. These resins have a melting point lower than the melting point of the metal, and when lined with these materials, the liner is burned by the heat of welding at the time of welding seam, so the liner is removed with the liner in advance and the liner is applied to the seam after welding. Or lining the whole tube and mechanically joining the groove joint or ring joint other than welding. In the case of welded joints, the anticorrosive treatment of the inner surface near the weld is difficult to access inside the pipeline, especially for small diameters. Therefore, the joining of the lined pipe material has been developed a mechanical joint method other than welding. In general, a ring joint and a groove joint are used, and in a specific field, for example, in the joint of the coated steel pipe described in Korean Patent Registration No. 100527842, a low height cast steel flange having a packing receiving groove and a steel pipe inclined receiving groove at one end of the steel pipe is formed. It shows that the anti-corrosion material can be coated on the entire inner and outer surfaces of the steel pipe, which is welded and includes the cast steel flange.

1 is a conventional ring joint to prevent leakage of the fluid flowing in the pipeline is maintained by the airtight contact of the packing 120 in contact with the tube (101). In addition, the joint of the Republic of Korea Patent No. 100527842 coated steel pipe is welded in the field, so that the joint is an advantage that can be lining the entire pipe. All the joints of the ring joint or coated steel pipe block the leakage of fluid by the close contact with the pipe of the packing, but it is difficult to match the center of the pipe to be joined at a certain site where the environment is poor, or the pressure change in the pipe is large. Or, if the pressure applied to the packing is uneven in some parts due to the instantaneous negative pressure during opening and closing of the valve, this may cause a short time leakage. In particular, if the pipe is bent at a certain angle from the seam, continuous leakage is a concern.

Accordingly, an object of the present invention is to improve a jointing method and a jointing apparatus for blocking the leakage of fluid at the joint of a pipe lined with resin and enduring all mechanical loads related to the pipe.

In the present invention, when the tube is lined with resin for the above purpose, the liner is first bonded and sealed, and then a mechanical joint, that is, a groove joint or a ring joint, or a joint of the coated tube is applied to the liner having elasticity. In addition to the cladding function for the method, it has a function to block leakage, and in connection with the strength of the pipe, the structure and role of the mechanical joint such as the conventional ring joint or groove joint are changed to be suitable for the joint method according to the present invention. The above object can be attained by making it quench.

In spite of the disadvantages of construction site, the eccentricity of construction, poor straightness, etc. in the joint of lined pipe, it reduces the risk of leakage compared to the existing mechanical joint method and also improves The lining allows longer pipe life by preventing corrosion at the joints. In addition, when joining by liner only, it is economical to omit piping elements such as elbows.

1 is a cross-sectional view of a known ring joint.
Figure 2 is a tube lined with resin inside.
3 is a cross-sectional view of the liner bonded ring joint according to the present invention.
4 is another embodiment of the liner bonded ring joint according to the present invention.
5 is another embodiment of the liner bonded ring joint according to the present invention.
6 is another shape of the liner bonded joint packing according to the present invention.
7 is a cross-sectional view of the liner bonded groove joint according to the present invention.
8 is a cross-sectional view of the liner bonded flange joint according to the present invention.
9 is a cross-sectional view of the liner bonded flare joint according to the present invention.
10 is a cross-sectional view of a liner bonded 90 degree flare joint according to the present invention.
11 is a cross-sectional view of another embodiment of a liner bonded flare joint in accordance with the present invention.
12 is a cross-sectional view of another embodiment of a liner bonded flare joint in accordance with the present invention.
Fig. 13 is a sectional view of a liner bonded flare joint of a bare tube according to the present invention;
Figure 14 is an example of a joint by joining only the liner according to the present invention.

The jointing method of a pipe lined with resin according to the present invention is to first join the liners of two pipes to be jointed integrally, and then to assemble the joints according to the pipes. It consists of The resin is a synthetic resin, preferably polycondensation resins, such as polymerized resins such as polyethylene, polypropylene, acrylic, fluororesin, elasticity and high elongation, synthetic rubbers and polycarbonates. In addition, the resin may contain fibers, metal wires, etc. in the resin layer to improve the function. Referring to the cross-sectional view of the pipe lined with resin in the above, referring to the cross-sectional view of FIG. 2 is a pipe lined with resin 102 on the inner surface of the pipe 101 to prevent corrosion of the pipe or to improve other functions. Pipe lined with resin is shipped from the factory with a certain length at the end of the pipe to be welded. In addition, the outer surface of the pipe is also lining most of the case, but it is natural that the present invention can be applied, and does not affect the contents of the present invention, the description of the outer lining in the following examples will be omitted. In the above, the joining method is a fusion method in which a liner of two pipes is heated by a known heating means and the liners heated above the melting point are pressed against each other to be adhered to each other, and a liner of the two pipes is heated to separate the two liners having a molten surface. Welding methods for melting, filling, and bonding the filler metal, or other known methods for attaching two liners, such as ultrasonic welding or the use of an adhesive. In the above, the joint comprises a known mechanical joint, such as a groove joint, a ring joint, and the like, connecting the two pipes and a joint for joint according to the present invention.

1. Looking at the method (procedure) of the liner bonded joint,

1) Cleaning: Clean the liner at the ends of the two pipes to be jointed with a detergent such as alcohol.

2) Liner Bonding: The ends of the liner of two pipes are heated to bond and cool.

3) Assemble joint: Assemble joint by extrapolating to joint and tightening bolts.

2. Looking at the embodiment of the liner bonded ring joint according to the present invention,

2-1. Figure 3 is an embodiment of the liner bonded ring joint according to the present invention the inner surface and the end of the tube 101 is lined with a resin 102 and the liner junction 107 is a portion joining the ends of the liner of the two pipes In most cases, the butt joint has a convex projecting shape. The joint housing 110 preferably has a rigidity equal to or greater than that of the pipe jointed with synthetic resin or metal. The shape of the joint housing 110 is divided into two or more on the circumference according to the diameter of the pipe for the convenience of assembly and handling, and bolt holes (not shown) at both ends of the divided portion (hereinafter referred to as a split piece). Bracket (not shown), which is attached to the sieve, is formed to protrude and surround the joint as a whole, and the central part of the inner part covers the joint of the two pipes and is a straight line 114 parallel to the axis of the pipe. A ring housing groove 112 is provided to support the joint from deformation, and to receive the ring 104 formed at the ends of the two pipes at both edges.

The structure of this housing is also applicable to liner bonded groove joints. The procedure for carrying out the joints is according to paragraph 1 above.

2-2. In another embodiment according to the present invention shown in Figure 4 when the internal pressure of the pipe to be joined is large, if the expansion of the joint is concerned about the expansion of the packing 120 is inserted between the housing 110 and the joint 107, the packing 120 is It is preferable to have high elasticity and excellent restoring force, and the cross section is rectangular and annular. In the central portion of the inner surface of the housing 110, a packing accommodating groove 111 for accommodating a packing having a rectangular cross section is provided.

5 shows an example of the case where the length of the pipe is long and the temperature difference is large.

Comparing FIG. 5 with the cross-sectional view of the existing ring joint of FIG. 1, in FIG. 1, the inner liner 102a of one pipe is separated from the inner liner 102b of the other pipe so that the fluid in the conduit is packed with the packing 120 and the metal tube. In the liner-bonded ring joint according to the present invention of FIG. 5, the liner 102 is joined to each other to form a continuous resin pipe in the liner-bonded ring joint according to the present invention. Risk is eliminated.

The joint procedure is

1) Extrapolation of packing: Extrapolate the packing 120 to one pipe and separate it sufficiently over a certain distance from the joint to prevent interference with the liner.

2) Cleaning: Clean the liner at the ends of the two pipes to be jointed with a detergent such as alcohol.

3) Liner bonding: The ends of the liners of both pipes are heated to bond and cool.

4) Precise packing position: Push the packing and place it in the center of the joint part 107.

5) Joint assembly: The joint 110 is extrapolated to the joint 107 to be positioned so that the ring 104 is seated in the ring receiving groove 112 and assembled by tightening bolts.

2-3. The packing 120 shown in Fig. 5 is formed of an annular high elastic material having a trapezoidal cross section and a concave groove formed at the bottom and top. The bottom groove 121 in the cross section of the packing is to prevent the long-term stress on the liner adhesive portion 107 by applying excessive or continuous pressure on the liner adhesive portion 107 in response to the protrusion surface generated when the liner is adhered. The concave groove 122 is formed with the adhesive portion 107 of the liner when the liner made of a resin having a linear expansion coefficient larger than that of the metal is expanded when a shocking force, ie, a water hammer occurs, or when the length of the metal tube is increased due to a change in temperature. The packing 120 is to serve as a kind of air pressure tank to be pushed toward the housing 110 side at the same time.

The compression portion of the trapezoidal side of the packing, that is, the inclined portion 123, when the housing 110 is tightened, the packing 120 is also subjected to a compressive force acting on the packing 120 toward the edge of the packing 120 Since the compressive force is to be greater than or equal to the inclination of the groove 115 for receiving the packing 120 of the housing 110. The packing 120 may have various shapes as shown in FIG. 6 in addition to the trapezoid, but may include a groove 122 on the top surface, a groove 121 on the bottom surface, and a compression part 123 on the side surface. Since the packing 120 is annular, the resin of the two pipes to be joined should be fitted in advance on the outer surface of the pipe (indicated by 'extrapolation' in the present invention) and spaced apart from the joint 107 so as not to interfere with the bonding operation.

The packing 120 is elastic and may be rubbery, but it is a type corresponding to the type of transport fluid in the pipeline in case of leakage. Natural rubber, nitrile rubber, styrene- It is preferable to use any one of butadiene rubber, chloroplan rubber, butyl rubber, ethylene propylene rubber, acrylic rubber, fluorine rubber, silicone rubber and butadiene rubber.

2-4. The housing 110 of FIG. 5 has an annular groove (packing accommodation groove) 111 for accommodating the packing 120 at the center of the inner surface thereof, and a ring welded to the end of the pipe as a ring accommodation groove 112 at the inner edge thereof. An annular groove for accommodating 104 is formed. The center of the packing accommodating groove 111 is gradually inclined in parallel with the central axis of the housing 110 so that the edge of the packing 120 is compressed more than the center portion when the housing 110 is assembled. Therefore, the seal is larger than the inclination of the packing edge.

The ring receiving groove 112 has a trapezoidal cross section to constrain the ring 104 and the pipe to be in a constant position as the housing 110 is tightened. In addition, the ring receiving groove 112 is wider than the ring 104 to allow a certain degree of displacement so that it can cope with expansion and contraction due to thermal expansion or pressure change in the pipeline.

2-5 The housing (110) is a case surrounding the joint and is responsible for all the loads associated with the joint, and also for the convenience of manufacturing and handling depending on the diameter of the pipe to receive the packing 120, the ring 104 and the joint It consists of two or more separation pieces, and a bolt hole is formed in the opposing part of each separation piece, and the bolt is inserted into this bolt hole at the time of assembly to tighten the nut, and the housing constrains two pipes as one cylinder to realize a joint. .

2-6. The ring 104 of FIG. 5 is circular or rectangular or rounded outside of a square, and is welded to the pipe so that the ring receiving groove 112 of the housing 110 is caught therein to prevent detachment of the pipe. Done.

3. Looking at the embodiment of the liner bonded groove joint according to the present invention,

The joint procedure is as follows and the structure in which the joint is performed is shown in FIG.

3-1 Joint Procedure

1) Extrapolation of packing: Extrapolate packing 120 to one side pipe and separate it sufficiently over a certain distance from the joint so as not to interfere with the liner.

4) Packing Position: Push the packing 120 and place it in the middle of the joint.

5) Assembling the joint: Position the joint by extrapolating it to the joint, so that the key 113 of the liner bonded groove joint is seated in the groove 105 formed in the pipe, and the housing 110 and the two pipe are fixed by tightening the bolt. do.

3-2. The difference between the liner bonded groove joint of FIG. 7 and the conventional groove joint is that the liner of the existing groove joint is separated from the liner of the other pipe so that the fluid in the conduit is applied to the adhesion between the packing 120 and the outer surface of the tube 101. In the liner bonded groove joint according to the present invention of FIG. 7, the liner 102 is joined to each other to form a continuous resin pipe, so that the fluid in the pipe is sealed with the liner 102 to eliminate the risk of leakage. will be.

The structure of the 3-3 liner bonded groove joint is similar to that of the liner bonded ring joint, except that the groove 105 is formed instead of the ring 104 formed in the pipe, and the groove 105 is known in a known manner. It is mainly roll forming in thinner tubes and cutting in thicker tubes. The key 113 formed at the edge of the housing 110 of the liner bonded groove joint is annular so as to be coupled to the groove 105 of the pipe, but slightly smaller than the width of the groove 105 to expand and contract the pipe according to the temperature and pressure. To be absorbed. The remainder of the liner bonded groove joint is the same as the liner bonded ring joint.

4. In the embodiment of the liner bonded flange joint according to the present invention, the structure in which the joint is performed is as shown in FIG.

4-1. Looking at the joint procedure: 1) Cleaning: Clean the liner 102 at the ends of the two pipes to be jointed with a detergent such as alcohol.

2) Liner Bonding: The liner 102 at the ends of two pipes is heated to melt, glue and cool.

3) Insert the bolt 132 into the bolt hole 131 formed in the flange 130 and tighten with a nut 133. At this time, the liner joint is not subjected to excessive compressive force.

4-2. Compared to the conventional flanged joint liner shown in Figure 8, the conventional flanged joint seals between the flange and the flange to realize the seal, but in the liner-bonded flange joint liner 102 of one pipe The liner 102 of the other pipe is joined to each other to form a continuous resin pipe, so that the fluid in the pipe is sealed with a resin, thereby eliminating the risk of leakage.

5. In the embodiment of the liner bonded flare joint joint according to the present invention, the structure in which the joint is performed is shown in FIG.

5-1. The procedure of the joint is as follows: 1) Extrude the end of the pipe with a dilator (not shown). At this time, in the case of the fixed flange 130, first to extrapolate the flanges to the ends of the two pipes, respectively, expansion, but in the case of articulated or split flanges first to expand the pipes and then extrapolate the flanges to the ends of the pipes.

2) Cleaning: Clean the ends of the liners of the two pipes to be jointed with a detergent such as alcohol.

3) Liner Bonding: The liner ends of two pipes are heated to melt and bonded, and welded and cooled using filler materials made of the same resin as the liner, if necessary.

4) Insert the bolt 132 into the bolt hole 131 formed in the flange 130 and tighten the nut 133.

5-2. The liner bonded flare joint shown in FIG. 9 is a resin-lined tube that can be cut in situ and tightened soon after expansion. The flare 106 allows the flange 130 to have a function of a locking jaw to prevent the flange 130 from being separated from the pipe. Accordingly, the shape of the flare 106 can be various, and in FIG. 9, the inclination angle formed by the pipe axis and the flare 106 is less than 90 degrees, and an inclination angle of 10 to 45 degrees is generally preferable.

5-3 shows an example in which the inclination angle of the flare 106 is 90 degrees, and FIG. 11 shows an example of another embodiment according to the type of mechanical joint of another flare joint. The joint procedure is the same as 5-1.

5-4 shows another example of applying the housing to the flare joint.

Joining procedure 1) Extrapolation of packing: Extrapolate packing 120 to one side pipe and separate it sufficiently over a certain distance from the joint 107 so as not to interfere with the liner.

2) The end of the pipe is expanded with an expansion tube (not shown). At this time, in the case of the fixed flange 130, first to extrapolate the flanges to the ends of the two pipes, respectively, expansion, but in the case of articulated or split flanges first to expand the pipes and then extrapolate the flanges to the ends of the pipes.

3) Cleaning: Clean the ends of the liners of the two pipes to be jointed with a detergent such as alcohol.

4) Liner Bonding: The liner ends of two pipes are heated to melt and glued, if necessary, welded using natural filler made of the same resin as the liner and naturally cooled.

5) Packing position: Push the packing to the center of the joint 107.

6) Joint assembly: The joint is extrapolated to the joint 107, and the assembly is assembled by inserting and tightening the bolt 132 into the bolt hole 131 formed in the housing 110.

The length of the housing 110 is longer than the length between the latching jaws of the two pipes formed by the expansion pipe to correspond to the expansion and contraction of the pipe due to temperature and pressure.

6. Another example of the liner bonded joint method of pipe according to the present invention.

In the case of grooved joints or ring joint joints of metal tubes not lined with resin, in order to reduce the risk of leakage, the ends of the two pipes are expanded as shown in FIG. 13, and the liner 102 is bonded after lining the pipes with resin. And by combining the joint 110 can be applied to the liner bonded joint of the present invention.

7. Another example of the liner bonded joint method of pipe according to the present invention.

If the joints of the resin-lined tubes do not have too much force on the joints, additional mechanical joints may not be needed. In this case, simply joining the liners can end the joint. This eliminates the need for additional response to the expansion and contraction of pipes due to temperature in long lengths of pipes, which simplifies operation and is economical. In addition, it is possible to make pipes that are bent at an arbitrary angle without the need for separate elbows (90 degree elbows, 45 degree elbows, 22.5 degrees, etc.) by lengthening the joint lengths or connecting resin tubes made of materials such as lining. .

14 is a part of a cross-sectional view of the pipe showing a state in which the length of the joint is bent and bent at an arbitrary angle in the liner joint only joint.

100: resin lining tube 101: original tube
102: inner resin liner 103: outer resin liner
104: ring 105: groove
106: flare 107: liner junction
110: housing 111: packing receiving groove
112: ring storage groove 113: key
114: parallel portion 115: inclined portion
120: packing 121: bottom groove
122: top groove 123: side slope
130: flange 131: bolt hole
132: bolt 133: nut

Claims

A joint method for joining a liner in a joint of a tube lined with resin.

A jointing method of a pipe lined with resin, in which a liner is joined when the liner is joined, or a resin pipe made of the same material as the liner is connected.

A jointing method comprising joining a liner in addition to a mechanical joint in a joint of a tube lined with resin.

The housing of the joint, which is used for the mechanical joint of the liner-bonded joint, is generally annular, formed of two or more divided pieces on the circumference, and bolt holes for assembly are formed between the divided pieces, and the pipes are formed at the edges on both sides of the inner surface. Key or ring receiving groove corresponding to the formed groove or ring is formed in the center portion of the joint housing, characterized in that the straight portion parallel to the axis of the pipe is formed to cover the joint of the two pipes.

The structure of the joint housing according to claim 4, wherein a groove for accommodating the packing is formed in a central portion of the inner surface of the housing of the joint, and a straight portion parallel to the central axis of the housing and an inclined portion for crimping the packing.

The structure of the joint housing, characterized in that the packing interpolated into the housing of the joint used for the mechanical joint of the joint to which the liner is bonded is a highly elastic resin having an annular and rectangular cross section.

The packing interpolated into the housing of the joint used for the mechanical joint of the joint to which the liner is bonded is annular, and its cross section is either rectangular or trapezoidal, and the structure of the joint housing characterized in that a groove is provided on the upper and lower surfaces.

The packing interpolated into the housing of the joint used for the mechanical joint of the liner bonded seam is characterized by the inclination of the side of the joint being equal to or less than the inclination of the housing so that the edge of the packing is tightened more than the center part when tightening the housing. The structure of the joint housing.

A method of jointing a pipe lined with resin, characterized in that the pipe is expanded, the liner is joined, and a mechanical joint is added.

A method of jointing lined with resin, wherein the angle of inclination between the axis of the pipe and the flare is 90 degrees or less when expanding the tube for joining the liner of the lined tube with resin.

A method of joining a pipe, characterized in that the joint is expanded and the liner is lined with resin, or the liner is joined without expansion and the liner is joined.