JPS5838216B2 - Kantai Menhi Fukusetsubi Niokeru Kantanbu Seal Hojisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for applying plastic coating to the inner surface of metal pipes such as steel pipes using plastic powder, or in other pipe inner surface coating equipment, for coating the ends of pipes of different diameters. This invention relates to a pipe end seal holding device that can rotatably hold the pipe in an airtight state while preventing slippage.

Conventionally, equipment that performs plastic coating by circulating plastic powder suspended in gas through a preheated and rotating metal tube and melting and adhering the plastic powder to the inner surface of the tube is as follows: As shown in FIG. 1, a front seal holding device 11 and a rear seal holding device 1 that can be moved in the tube axis direction by a fluid pressure cylinder or the like.
2, a rotary joint 15 and an expansion joint 16 are interposed in the pipe line that tightens and holds the metal pipe body 13 and connects the front seal holding device 11 and the plastic powder supply equipment 14, and the primary gas is introduced. A rotary joint 19 and an expansion joint 20 are provided in a conduit connecting the rear seal holding device 12 and a plastic powder separation and recovery equipment 18 such as a cyclone, and a secondary gas inlet 21 is provided.
The plastic powder separation and recovery equipment 18 and the plastic powder supply equipment 14 are connected by a reflux pipe 22, and the holding pipe 3 is rotatably supported by the casing 1 of the rear seal holding device @ 12 via a bearing 2. A tube end seal retaining member 24 with an elastic ring 23 is screwed together, and a drive device 25 connects the tube end in the rear seal retainer 12 via the rotary part in the front seal retainer and the tube body 13. A type in which the seal holding member 24 and the holding tube 3 are rotated is known.

However, in this type of tube inner surface coating equipment, the rotational force of the tube 13 is transferred to the rear seal holding device 1 due to the frictional force between the end surface of the tube 13 and the elastic ring 23 pressed against the end surface.
2, and the dead weight of the tube end seal holding member 24 and the holding tube 3 is relatively large.
However, since the torque for transmitting rotational force decreases in proportion to the pipe diameter, if the pipe diameter is small, a slip phenomenon will occur between the pipe body 13 and the elastic ring 23, which may cause the elastic ring 23 to break. This increases the rate of wear of the elastic ring 23, making it necessary to replace it frequently, and the replacement work shortens the operating time of the equipment, which is uneconomical and increases costs.

In addition, during the coating process, the airtightness may decrease due to damage or wear of the elastic ring 23, and uneven rotation of the holding tube 3 and tube end seal holding member 24 may occur, resulting in uneven coating thickness. There are drawbacks such as smearing and poor appearance.

SUMMARY OF THE INVENTION The object of the present invention is to provide a fitting for a tube end seal retaining device in a tube inner surface coating facility that eliminates the above-mentioned drawbacks.

Next, the present invention will be explained in detail using illustrated examples.

Figure 3 shows a large diameter pipe end seal holding unit 5 attached to the casing.
This figure shows a state in which a retaining tube 3 equipped with a connecting female thread is attached to a bearing 2 on a casing 1 of a rear seal retaining device 12 in the tubular inner surface coating equipment shown in FIG.
A male threaded portion of a holding member 27 having a circular cross section and a large diameter hole 26 at the front end is removably screwed into the holding tube 3, and the annular shape of the large diameter hole 26 A large-diameter elastic ring 4 made of fluorocarbon rubber for press-fitting the end surface of a large-diameter pipe is in contact with the bottom surface, and a large-diameter holding ring 28 screwed into the dog-diameter hole 26 is attached to the outer periphery of the front surface of the large-diameter elastic ring 4. A truncated cone 29 is formed on the inner periphery of the large-diameter restraining ring 28, which is pressed against the side portion and fitted onto the outer peripheral surface of the large-diameter elastic ring 4. The holding member 27, the large-diameter elastic ring 4, and the large-diameter restraining ring 28 constitute the large-diameter tube end seal holding unit 5.

FIG. 4 shows a state in which the large diameter tube end seal holding unit 5 is removed and the small diameter tube end seal holding unit 10 is attached, and shows the main holding member 6 screwed to the holding tube 3. A tubular support shaft of an auxiliary holding member 8 is rotatably fitted to the front end of the auxiliary holding member 8 via a bearing 9, and a ring-shaped bottom surface of a dog diameter hole 30 at the front of the auxiliary holding member 8 is made of fluoro rubber. A small-diameter elastic ring 7 for press-welding the end surface of a small-diameter pipe is brought into contact with the small-diameter elastic ring 7, which is held down by a small-diameter holding ring 31 having the same structure as the large-diameter holding ring 28, and is held by the main holding member 6, the auxiliary holding member 8, and the bearing. 9. The small diameter elastic ring 7 and the small diameter restraining ring 31 constitute a small diameter tube end seal holding unit 10.

According to experiments, when holding the rear end of a 15A tube, the torque required to rotate the tube end seal holding member 24 and the holding tube 3 in the conventional rear seal holding device shown in FIG. 9. While there is O Kyα, the third
The torque required to rotate the auxiliary holding member 8 and the parts fixed thereto in the embodiment of the present invention shown in the figure was 0.01 Ky, which was significantly smaller than that of the conventional one.

According to this invention, the small diameter tube end seal holding unit 10
When the small-diameter tube body 32 tightly gripped by the small-diameter elastic ring 7 rotates, the small-diameter tube end seal holding unit 10, which has a small self-weight, is only rotated by the small-diameter tube body 32, and the small-diameter tube end seal holding unit 10, which has a small self-weight, is rotated by the small-diameter tube body 32, and the small-diameter tube end seal holding unit 10, which has a small self-weight, Since the holding tube 3 and the large-diameter tube end seal holding unit 5 are in a stopped state or a state where they hardly rotate, it is possible to prevent a slip phenomenon from occurring between the end surface of the small-diameter tube body 32 and the small-diameter elastic ring 7. Therefore, it is possible to prevent the small diameter elastic ring 7 from being damaged or prematurely worn out, thereby solving the problem of uneconomical and high costs, and to ensure smooth rotation while maintaining a perfect seal at the pipe end. This makes it possible to form a coating with a uniform thickness and a beautiful appearance.Furthermore, when coating the inner surface of the large-diameter tube body 33, the small-diameter tube end seal holding unit 10 is removed and the large-diameter tube end is sealed. Since it is only necessary to install the seal holding unit 5, the casing 1 and the holding tube 3 can be used in common. Therefore, when applying plastic coating to the inner surfaces of large diameter pipes and small diameter pipes, it is necessary to install the coating equipment for large diameter pipes and the coating equipment for small diameter pipes. There is no need to use both pieces of equipment, and the main parts of the large-diameter pipe coating equipment can be shared and only some parts need to be replaced, resulting in benefits such as lower equipment costs.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing equipment for coating the inner surface of a tube body with yd plastic powder, and FIG. 2 is a longitudinal sectional side view showing a conventional rear seal holding device. 3 and 4 show an embodiment of the present invention, and FIG. 3 is a longitudinal sectional side view showing a state in which the large diameter pipe end seal holding unit is attached and the large diameter pipe body is held. FIG. 4 is a longitudinal sectional side view showing a state in which the small diameter tube end seal holding unit is attached and the small diameter tube body is held. In the figure, 1 is a casing, 2 is a bearing, 3 is a holding pipe,
4 is a large-diameter elastic ring for pressure-welding the surface of a large-diameter tube, 5 is a large-diameter tube end seal holding unit, 6 is a main holding member, 7 is a small-diameter elastic ring for pressure-welding the end surface of a small-diameter tube, 8 is an auxiliary holding member, and 9 is a bearing. ,
10 is a small diameter tube end sill holding unit, 11 is a front seal holding device, 12 is a rear seal holding device, 25 is a drive device, 27 is a holding member, and 28 is a large diameter restraining ring.

Claims (1)

[Claims] 1 A holding tube 3 which is rotatably supported by a casing 1 via a bearing 2, and a large diameter pipe which is removably connected to the holding tube 3 and is equipped with a large diameter elastic ring 4 for press-welding the end surface of the large diameter tube. An auxiliary holding member 8 having a small-diameter elastic ring 7 for press-fitting the end surface of a small-diameter tube rotates via a bearing 9 to the tube end seal holding unit 5 and the main holding member 6 which is detachably connected to the holding tube 3 . A combination of a tube end seal retaining device in a tube inner surface coating facility comprising a freely supported small diameter tube end seal retaining unit 10.