JPS6012219B2 - Structure of pipe lining - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pipe lining structure that is simple and easy to manufacture, and that can prevent the lining material from falling off.

Conventionally, in this type of lining structure, as shown in FIG. Both ends 3a and 3b are connected to the flange part 4a from each closed part of the pipe 1.
, 4b, or, as shown in FIG. 2, a porous cylindrical reinforcing member 5 is embedded in the lining material 3 lined on the inner wall la of the pipe 1 (Utility Model Act 53-51181). No.) is known.

However, in the former case, since the distance between the dovetail grooves 2 is relatively long, when the lining material 3 expands and contracts in the mari direction due to thermal changes in the fluid flowing inside the pipe 1, the distance between the dovetail grooves 2 and the oblique side surface There is a drawback that if a gap is created in the tube and a force is applied in a direction perpendicular to the axis, the lining material 3 easily falls off from the tube inner hole. On the other hand, in the latter case, the inner and outer lining materials of the cylindrical shape are connected through the lining material filled in each hole 6 of the reinforcing member 5, so by increasing the density of the holes 6,
Although the inner and outer lining materials can be firmly bonded and peeling can be prevented, there is a drawback that the thickness of the lining material 3 becomes unnecessarily thick. The present invention was made in view of the above-mentioned drawbacks of the secondary pipe, and involves forming a large number of grooves with a small pitch on the inner wall of the pipe, and extending the tops of the peaks left between the grooves above each groove. By tilting or crushing the tube in the axial direction so as to close it, and lining the inner wall of the tube including the groove with the lining material, the bonding strength between the lining material and the tube is increased and the lining material is prevented from peeling off or falling off due to expansion and contraction, etc. The present invention provides a pipe lining structure as described above.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 3 is a sectional view of a main part showing the basic structure of the pipe lining according to the present invention.

In the figure, 10 is a V-shaped thread groove with a small pitch formed on the inner wall of the tube 1, 11 is the portion left between the thread grooves 10, that is, the mountain portion forming the thread groove 10;
Reference numeral 2 denotes a lining material that lines the entire inner wall of the pipe including the thread groove 10, and the top portion 11a of the mountain portion 11 is lined with the thread groove 1.
The tube axis is tilted in all directions so as to block the upper part of 0. As the lining material 12, a strong thread-like substance such as polytetrafluorethylene is suitable, but various known materials such as rubber and polyurethane may also be used.
The key is to select and use them according to the fluid flowing inside the pipe. Next, an embodiment of a method for manufacturing a lining with the above structure will be described with reference to FIG. 4. After forming the thread groove 10 on the inner wall of the tube 1, a diameter R(D,
<R<D2) is pressed into the steel ball 15 as a pressing member using a hydraulic press or the like, and the top 11a of the mountain portion 11 is laid down sideways in the direction of the pipe axis, and then the lining material 12 is inserted into the pipe as shown in FIG. Line the inner wall of 1. The steel ball 15 is the tube 1
Although it may be press-fitted from one closed portion 13 and taken out from the other opening portion 14, the horizontal direction of the top portion 11a of the mountain portion 11 may be changed. In this case, the steel ball 15 is press-fitted from one entrance part 13 to the center of the inner hole of the pipe 1 and taken out from the same open part 13, and then the pipe 1 is turned over and inserted from the other entrance part 14 as shown by the chain line. Press-fit the steel ball 15' into the remaining peak part 1.
What is necessary is just to lay down the top part 11a of 1 in the opposite direction. When taking out the steel ball 15' that was press-fitted from the entrance part 14, since all the peak parts 11 are turned sideways, which opening 13,
It is possible even from 14. Thus, according to the structure of the pipe lining having such a configuration, the lining material 12
Since the screws bite into the inner wall of the pipe finely at the thread pitch interval and are joined together, the bonding strength is large, and even if the lining material 12 expands or contracts due to thermal changes, the dimensions between each biting part are short, so dimensional changes can be ignored. It is possible,
Therefore, peeling and falling off of the lining material 12 can be prevented.

Further, as described above, if the horizontal directions of the top portions 11a of the mountain portions 11 are made in opposite directions in the upper and lower halves of the tube inner hole, a stronger peeling prevention structure can be achieved. Further, thread processing and insertion of the steel balls 15 are very easy, and manufacturing is possible at low cost. Figures 5a, b, and c show other embodiments of the molding method.

In this embodiment, the thread grooves 10 are formed deeply, and the tops 11a of the crests 11 are intermittently laid down at equal pitches so as to be close to or in contact with adjacent ridges 11. In this case, as shown in FIG.
The spaced apart portion 12A filled between the tubes is firmly and integrally connected at both ends to a lining layer lining the inner wall of the tube. Thus, by providing such a separated portion 12A, the lining material 12 is sewn over the entire surface of the inner wall of the pipe, so the bonding strength is extremely high, and even if an external force is applied in any direction, the lining material The material 12 will not peel or fall off.

FIG. 6 is a front view showing the cutting edge of a tool used to intermittently topple the top portion 11a of the mountain part 11 shown in FIG. 5 sideways at equal pitches.

This tool 2 is formed into a cylindrical shape, and a plurality of large diameter portions 21 having an outer diameter somewhat larger than the outer diameter of the tool 20 are integrally formed on the outer circumferential surface of the cutting edge portion 20A at the tip thereof and in the axial direction. A slit portion 22 is formed between these large diameter portions 21 . Therefore, when the cutting edge portion 20A of this tool 20 is press-fitted into the inner hole of the tube 1, the top portion 11a of the ridge portion 11 corresponding to the large ridge portion 21 is tilted sideways, and the ridge portion 11 corresponding to the slit portion 22 is tilted sideways. The peak portion 11a shown in FIG. 5 is left as it is, and the peak portion 11 shown in FIG. 5 is formed into a predetermined shape at once. Therefore, even in this case, machining is extremely simple, and known broaching can be applied. FIG. 7 is a sectional view of a main part showing still another embodiment of the molding method.

In this embodiment, the top portion 11a of the mountain portion 11 is crushed as shown in the figure to simultaneously close the upper portions of two adjacent thread grooves 10. In this case, the lining material 12 has a thick annular locking portion 23 formed at the thread groove 10 portion, and is joined to the lining layer at the neck near the top of the mountain portion 11 over the entire circumference. Therefore, even in this case, a strong bond is obtained, so that even if an external force is applied to the lining material 12 in any direction, there will be no dust that will cause the lining material 12 to peel or fall off.

As a method for forming such a peak portion 11, a secondary processing method called burnishing can be applied, as shown in FIG.

That is, in the inner hole of the tube 1 in which the thread groove 10 is formed, the tapered main drive shaft 25 whose tip is formed with a small diameter is connected to the tube axis and the shaft 0.
Align and insert the top part 11 of the mountain part 11 around it.
When a plurality of roller rods 26 are arranged for crushing a and the tapered main drive shaft 25 is rotated in the direction of the arrow, the roller rods 26 are rotated in the opposite direction with the rotation of the main drive shaft 25. The neck 11a of the portion 11 is gradually crushed as shown in FIG. Incidentally, in the above embodiments, the case where the thread groove 10 is formed on the inner wall of the pipe 1 has been described, but the present invention is not limited to this in any way, and a large number of ring-shaped grooves may be formed. .

In addition, the groove is not limited to the V-shape, but the square groove 3 shown in FIGS. 9a and 9b.
It is possible to make it into various shapes such as 0, U-shaped ledger 31, etc. Further, in the present invention, it is not necessary to form grooves all around the inner hole of the tube 1, and the grooves can be formed only in the necessary portions. As explained above, according to the structure of the pipe lining according to the present invention, a plurality of grooves with a small pitch are formed on the inner wall of the pipe, and the top of the mountain portion left between each groove is Since the tube is tilted or crushed in the tube axis direction so as to close the upper part, and the inner wall of the tube including the inside of the groove is lined with the lining material, the lining material can be firmly bonded to the tube.

Therefore, even if the lining material expands or contracts due to thermal changes or external force is applied, it will prevent the lining material from peeling off or falling off.
In addition to improving the durability of the product, it is extremely easy to process and mold and can be manufactured at low cost.

[Brief explanation of drawings]

1 and 2 are a longitudinal sectional view and a partially cutaway perspective view showing an example of the lining structure of a subordinate pipe, and FIG. 3 is a sectional view showing the basic structure of the pipe lining according to the present invention, 4
The figure is a diagram for explaining the method for forming the pipe lining, and FIG. Fig. 6 is a front view of the main part of the tool used to process the mountain portion shown in Fig. 5, and Fig. 7 shows still another embodiment of the forming method. FIG. 8 is a diagram showing a processing method for the mountain part shown in FIG. 7, and FIGS. 9a and 9b are sectional views of main parts showing other embodiments of the groove. 1...Pipe, 10...Thread groove, 11...Mountain part, 11
a... Neck part, 12... Lining material,
15... Steel ball, 20... Tool, 21...
・・・Large diameter part, 22...Slit part, 25...○ Active spinal cord with napa, 26...Roller rod. 1 figure, 2 figures, 3 figures, 3 figures, 4 figures, 5 figures, 6 figures, 7 figures, 8 figures, 9 figures

Claims (1)

[Scope of Claims] 1. A large number of relatively narrow grooves provided on the inner wall of the pipe, and ridges left between the grooves that are collapsed or crushed in the axial direction so that the tops close the upper portions of the grooves. and a lining material stretched over the inner wall of the pipe including the inside of the groove. 2. The pipe lining structure according to claim 1, wherein the top of the mountain portion is intermittently tilted or crushed in the axial direction so as to intermittently close the upper part of the groove.