JPH07276197A - Internal face grinding method for pipe and device therefor - Google Patents

Abstract

PURPOSE:To grind a metal pipe across its entire length always uniformly and stably by forming a grinding brush by planting the bristle grinding material made of a synthetic resin containing grinding grains therein and expandingly contacting at least one part of the grinding brush with the inner surface of the pipe. CONSTITUTION:A bristle planted member 14 planted lots of bristles 6 is inserted loosely to a grinding tool main body 11 A rotary shaft 13 is so hollow that air or liquid, etc., can be passed through thereinside. An operation liquid is sent in the hollow part of this rotary shaft 13 and gives a pressure to a rubber type elastic bag 15 assembled in the grinding tool main body 11 and expands the bristle planted member 14 in a diameter direction. An expanding pressure, namely a grinding force is regulated by the regulation of a given water pressure so that the grinding finish can be controlled freely from even the outside. Thereby, the inner surface of a long metal pipe can be ground uniformly without any unevenness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polishing an inner surface of a metal tube with abrasive grains, and more specifically, a synthetic resin thread-like or string-like bristle polishing material containing abrasive grains for polishing a grinding brush. The present invention relates to a method for polishing an inner surface of a pipe and a polishing apparatus for polishing the inner surface of a metal tube by rotating the grinding brush in the metal tube and moving it as necessary.

[0002]

2. Description of the Related Art The conventional polishing of the inner surface of a metal pipe with abrasive grains
As shown in FIG. 1, a sanding tool (sandpaper wheel) 1 in which sandpaper is radially formed is inserted into a metal tube, and then the shaft of the sanding tool is rotated and moved in the metal tube. I was polishing.

Alternatively, as shown in FIG. 2, a sandpaper 3 is attached to a gourd-shaped or hourglass-shaped polishing tool (top) 2.
Polishing was performed by swinging the steel tube 5 in the metal tube 4 in the axial direction.

Further, conventionally, as shown in FIG. 3, a synthetic resin bristle containing abrasive grains is cut into a predetermined length, which is sandwiched between two wires and twisted like a rope. There is a "twisting brush" that I made, but this "twisting brush"
Is used mainly by grasping it with a "drilling machine chuck" and rotating it. The purpose is to polish the length of the "brush" of 50 to 200 mm at most, and only the short one is polished. could not.

In addition, since the middle of one to several bristles is fixed by sandwiching it with a wire, this product not only easily breaks due to its resistance when contacted with the entire circumference of the inner surface of the pipe, The abrasion caused "unevenness and unevenness" in polishing like the paper wheel. Furthermore, if this is forcibly applied to a long tube, there is a risk that the "twisting brush" will dance like hitting the tube at the tip of the long rotating shaft and damage the inner surface of the tube.

Therefore, there has been no example of polishing the inner surface of a long and thin metal tube with bristles made of synthetic resin containing abrasive grains inside.

[0007]

The sanding work using sandpaper is also called a dirty, tight, and dangerous thing. Abrasive grains and sandpaper powder are turned into a large amount of dust, dust, and the like. Not only wipe the whole body of the worker and damage the health, but also when the abrasive grains of the sandpaper are not completely wiped off from the product,
This has a major drawback that it adheres to the inner surface of the metal tube during or after polishing to scratch the finished surface and ruin the product.

A further major drawback is that the abrasive grains of sandpaper, which is an abrasive, are easily separated from the main body of the polishing tool during the polishing operation. Due to the fate that the abrasive grains of the sandpaper are peeled off and the polishing tool is rounded, the sandpaper of the polishing tool must be replaced frequently.

Due to the removal of the abrasive grains of the sandpaper, the polishing tool must be frequently replaced in a long metal tube, so that the polishing of the inner surface of the long metal tube is not uniform. For example, a small diameter and a long length (for example, a diameter of 2
7.2 mm x wall thickness 2 mm x length 2000 mm)
There is always a fear that polishing leakage may occur in the middle of the (23.2 mm) metal tube. When an inspection is performed by cutting the middle of a metal tube that has actually been polished or an endoscope is used, it is found that, in a severe case, an unpolished portion is found.

The reason why sandpaper is used in spite of such drawbacks is that the polishing of the inner surface of a metal tube having a small inner diameter (diameter of 40 mm or less) has conventionally been accomplished only by polishing the sandpaper with abrasive grains. is there.

Therefore, the above-mentioned outer diameter 27.2 mm ×
2000 mm for polishing the inner surface of a thin metal tube with a wall thickness of 2 mm
The limit was to grind those with a length of mm 2.

[0012]

The problem to be solved by the present invention is to solve the conventional problem of dirty dust.

More importantly, it is necessary to always carry out uniform and stable polishing over the entire length of the metal tube without polishing leakage.

Further, it is a main object to increase the efficiency of polishing at the same time as extending the life of the grinding brush to eliminate unevenness of polishing due to replacement of the polishing tool.

[0015]

SUMMARY OF THE INVENTION According to the present invention, a bristle (bristles) abrasive material made of a synthetic resin containing abrasive grains is implanted to form a grinding brush. This is accomplished by making expanded contact with the inner surface of the tube.

Further, it is achieved by bundling a predetermined amount of bristles, implanting and fixing the bristles to form bristle bristling members, loosely fitting the bristle bristling members into the polishing tool body, and then expanding the bristle bristling members onto the inner surface of the tube.

Further, a predetermined amount of bristles are bundled, and the flocking / polishing tool main body having the bristles fixed thereto, that is, the grinding brush, is directly
This is accomplished by splitting two or more axially, and then expanding this to the inner surface of the tube.

Furthermore, it is achieved by enlarging and expanding the diameter of a spirally wound channel type bristle block on the inner surface of the tube.

[0019]

[Function] The bristle block configured as described above,
Or, by the centrifugal force due to the rotation of the bristle flocking member or the grinding brush, by the expanding force of the grinding brush itself,
Also, the bristles can be strongly pressed against the inner surface of the metal tube by the force of a screw incorporated in the shaft core, the action of a spring, or the pressure of a fluid.

The bristles are perpendicular to the inner surface of the tube,
Also, it is desirable to press strongly in the axial direction of the bristles, but this is not necessary. At this time, the bristles continuously wear, and preferably wear in the axial direction, continuously create a new abrasive grain surface and strongly polish the inner surface of the metal tube.

The bristle core material yarn in which the abrasive material is mixed is made into a filament material by uniformly mixing abrasive particles of a predetermined particle size such as silicon carbide, alumina, carborundum, and alundum into a nylon base material. It is processed into a string shape.

The thickness of the bristle core material yarn is usually one or several yarns as a unit, and when used, the diameter is
0.3-3.0 mm. When using a thin thread, 20
When bundling ~ 800 pieces as one unit to form a core material, 1
A denier of 10 to 10 is used.

One to a plurality of core yarns are prepared and are covered with a covering tape or a covering yarn, which are braided in a cylindrical shape, a spiral shape, or a cord shape, wound, fixed, and covered. It is desirable to be done.

The covering thread is preferably nylon type. The covering thread may be an adhesive obtained by dissolving a nylon resin in alcohol, and may be bonded and fixed to the bundled core material thread.

In the bristle block in which flocking is applied to the channels, a non-woven fabric, knitted fabric, or other nylon tape is sewn on with a squeezing thread as a covering tape on one side or both sides, and further adhered if necessary to cover. You should ring.

The present invention will be described in detail with reference to the following examples, but it goes without saying that the present invention is not limited to these examples. Further, in this embodiment, the same components are designated by the same reference numerals and the description thereof will be omitted.

[0027]

Example 1 The bristle shown in FIG. 4 (a) is a sun grit manufactured by Asahi Kasei Corporation and is composed of bristle yarn in which # 500 alumina abrasive grains are dispersed and mixed. The bristle 6 has a diameter of 0.45 mm and is planted on a channel fitting 7 having a width of 6 mm and a height of 7 mm to form a channel-type bristle block 8. 9 is a covering tape and 10 is a squeezing thread.

As shown in FIG. 4B, the channel type bristle block 8 is freely removably fitted and housed in the recess 12 of the main body 11 of the polishing tool so that the tip of the bristle 6 is slightly exposed. It becomes brush A.

Cooling air and cooling water are preferably fed into the metal tube so that the bristles 6 are not softened by the frictional heat of grinding and the tip is not melted. Further, the rotary shaft 13 is
If necessary, the processing liquid, the cooling liquid, the cooling air, etc. can be sent to the inside without forming the hollow.

The metal tube (not shown) may be fixed,
It can be rotated, preferably the tube end is sealed.

The inner surface of the metal tube is polished with this grinding brush A. The metal tube is a SUS304 stainless steel tube,
Both the outside diameter and the inside diameter are precisely drawn with a tolerance of ± 0.05 mm, and the outside diameter is 38.1 mm and the inside diameter is 33.7.
mm Thickness: 1.2 mm Length: 4000 mm Solution heat treatment (quenching at 1010 ° C. or higher) Pickling.

In the grinding brush A, the outer diameter of the grinding brush A is slightly smaller than the inner diameter of the stainless steel pipe when it is inserted into the pipe, and when the grinding brush A is rotated, it is against the inner surface of the stainless steel pipe. It is preferable that the bristles 6 are expanded by centrifugal force and pressed against the bristles 6 in the axial direction to bring them into contact with each other. Alternatively, the grinding brush A may be made larger than the inner diameter of the tube by a predetermined amount from the beginning.

The peripheral speed of the grinding brush A is generally 1000.
m / min or more is desirable, but in this case
It is 50 to 5000 rotations, preferably 2000 rotations.
The bristle block 8 can be further pressed from below by a spring (not shown) against the inner surface of the stainless steel pipe.

[0034]

[Embodiment 2] Embodiment 2 is shown in FIG. The bristle flocking member 14 in which a large number of bristles 6 are flocked is loosely fitted to the polishing tool body 11.

The rotary shaft 13 is hollow and allows air or liquid to pass through it. In this embodiment, the operation liquid is fed into the hollow of the rotary shaft 13 and pressure is applied to the rubber-like elastic bag incorporated in the polishing tool body 11 to expand the bristle bristle implanting member 14 in the diameter direction. By adjusting the applied water pressure, you can adjust the expanding pressure, that is, the grinding force,
The finish of polishing can be freely controlled from the outside.

[0036]

Fourth Embodiment A fourth embodiment shown in FIG. 6 is a polishing tool body 11 in which a large number of bristles are planted, and a direct grinding brush A is axially divided into two or more parts.
The divided grinding brush A expands to the inner surface of the tube and contacts the inner surface of the metal tube by the liquid pressure from the hollow shaft 13 and / or the centrifugal force due to the rotation of the shaft 13.

[0037]

Fifth Embodiment A fifth embodiment shown in FIG. 7 is a bristle block of a coil brush type, in which bristles having hairs implanted in a channel are spirally wound and loosely fitted on a shaft core 16. The outer diameter of the spiral bristle block 17 can be increased by pinching from both sides of the spiral. Alternatively, the spiral winding of the spiral bristles block 17 can be twisted and expanded to unroll. The width of this unroll can be adjusted freely. Furthermore,
The spiral bristle block 17 tightly fitted to the shaft core 16 can also be unrolled and expanded together by compressing and thickening the shaft core 16. The shaft core 16 includes a rod, a shaft, a wire, and the like, as long as it is a member capable of enlarging or reducing the spiral bristles block.

The above-mentioned polishing tool body 1 of the grinding brush A
1 and / or the shaft core 16 is internally mounted as necessary, spring repulsion, rubber member, rubber elastic bag expansion, wedge member press fitting, screw shaft compression (not shown), etc. It can be expanded by the method of.

The present invention is not limited to the above-mentioned embodiment, and various kinds of bristles can be used, and the bristle block is not only a straight flocked channel or flocked roll, but also a spiral channel-shaped bristle block or a special bristle block. JP-A-62-216680, JP-A-4-
It goes without saying that the bristle of the known aspect described in Japanese Patent No. 315582 and the like can be applied as the bristle block. The spiral winding method is not limited to the embodiment, and a known winding method can be applied from dense coil winding to loose helical winding. The hollow rotating shaft can not only allow liquid to pass therethrough, but can also operate to expand or contract the bristle block by passing a rod, wire, or the like. The work material is not limited to stainless steel pipe,
Applicable to aluminum alloys and other metals. At the time of grinding with this bristle block, an appropriate fluid such as cooling air, cooling water, processing liquid, cleaning liquid can be flowed in the metal pipe.

As bristle mixed with abrasive grains, Sungrid (Asahi Kasei), Tynex (DuPont), Trigret (Toray) and others can be used.

Although the above description has been given with reference to the embodiment for dealing with a thin pipe, the present invention is not limited to this, and it is needless to say that the present invention can be applied to a large-diameter pipe which is easier to polish. The grinding brush does not need to expand and contact the entire inner surface of the tube for polishing, and the tube may be rotated while contacting and polishing a part of the circumference.

As described in detail above, according to the present invention,
Various effects as listed below can be obtained.

(1) Dust pollution that has been caused by conventional buffing and sandpaper wheel polishing, which are typified by dirt, severeness, and tightness, can be eliminated. (2) Since the working fluid can be used, the grinding brush can be cooled. (Deformation temperature of nylon base material ・ 90 ℃ melting temperature ・ 210
(° C) Rotating at high speed requires cooling due to frictional heat from grinding. (3) The life of the grinding brush is significantly extended. (4) The inner surface of the long metal tube is uniformly polished without unevenness. (5) Polishing of the inner surface of a metal pipe having a small diameter and a long length, which has been extremely difficult in the past, comes. (It is possible to polish the inner surface of a metal tube that is twice or three times as long as the conventional one.) (6) Obviously, there will be no polishing leakage and no defective products. (7) It can be automated. (8) The polishing rate is increased 2-3 times, the productivity is remarkably increased, and the cost is reduced. (9) If the product of the present invention is further electropolished, the time required for expensive electropolishing is greatly shortened, and the electrolytic polishing finish becomes less expensive.

[Brief description of drawings]

FIG. 1 is a perspective view of a conventional sandpaper foil.

FIG. 2 is a perspective view of a top wound with a conventional axial swing type sandpaper.

FIG. 3 is an explanatory view of a conventional “twist brush”.

FIG. 4A is a perspective view of a channel type bristle block. (B) is a perspective view showing a state in which a channel type bristle block is loosely fitted in the polishing tool body.

FIG. 5 (A) is a perspective view of a bristle-implanted bristle block. (B) is a partially longitudinal perspective view showing a state in which the flocked bristle block is loosely fitted to the polishing tool body.

FIG. 6 is a perspective view of a grinding brush in which bristles are directly planted on a polishing tool body and can be enlarged.

FIG. 7 is a vertical cross-sectional explanatory view of a grinding brush in which a spiral wound bristle block is loosely fitted.

[Explanation of symbols]

 A Grinding brush 1 Sandpaper wheel 2 Sandpaper 3 Sandpaper 4 Metal tube 5 Steel wire 6 Bristle 7 Channel 8 Bristle block 9 Covering tape 10 Tightening thread 11 Abrasive tool body 12 Recess 13 Rotating shaft 14 Bristle flocking member 15 Rubber elasticity Bag 16 shaft core 17 spiral bristle block

Claims (12)

[Claims] 1. In the inner surface polishing of a tube with abrasive grains, a bristle block is formed by flocking synthetic resin thread-shaped or string-shaped bristle (bristles) polishing material containing abrasive grains inside, to form a bristle block. The block is loosely fitted to the body of the polishing tool to form a grinding brush, and the grinding brush at least partially expands and contacts the inner surface of the tube to polish the inner surface of the tube and to successively wear it while wearing it. A method for polishing the inner surface of a pipe, characterized in that a new abrasive grain surface is created. 2. The bristle block is planted in a channel to form a spiral bristle block, and the bristle block is loosely inserted, loosely fitted, or tightly fitted to a shaft core,
The inner surface of the tube according to claim 1, wherein a grinding brush is configured so as to be expanded to the inner surface of the tube, the grinding brush is inserted into the inner surface of the tube, which is rotated and moved as necessary. Polishing method. 3. A bristle block is formed by bristling said bristles into a channel, and the bristles block is loosely fitted and housed in a recess provided in a grinding brush body to form a grinding brush. The method for polishing an inner surface of a pipe according to claim 1, characterized in that the inner surface of the pipe is inserted into a tube, the tube is rotated and, if necessary, moved. 4. A grinding brush is constructed by inserting two or more bristle bristle implanting members into a recess formed in a grinding brush body in the axial direction so as to be loosely fitted therein, and the grinding brush is formed on the inner surface of the tube. The method of polishing an inner surface of a pipe according to claim 1 or 3, wherein the method is inserted, rotated, and moved as necessary. 5. A grinding brush is constructed by dividing a flocked grinding brush main body, in which bristles are directly flocked by implantation, into two or more parts in the axial direction of the grinding brush main body, and expanding this into the inner surface of the tube. 5. The method for polishing an inner surface of a pipe according to claim 1, 3, or 4, wherein the grinding brush is inserted into the inner surface of the pipe, and the brush is rotated and moved if necessary. 6. The thread-shaped or string-shaped bristle is pressed against the inner surface of the tube in the axial direction of the bristle, is consumed in the axial direction, and is created.
The method for polishing an inner surface of a tube according to claim 5. 7. The thread-shaped or string-shaped bristle is pressed against the inner surface of the pipe by a rod, a wire, or a screw, by the action of a spring, and also by a centrifugal force. Item 8. A method for polishing an inner surface of a tube according to any one of Items 7. 8. The bristle block, the bristle member, and the split flocked grinding brush are pressed against the inner surface of the tube by the pressure of the fluid introduced into the grinding brush body. The method for polishing an inner surface of a tube according to any one of 1. 9. The method for polishing an inner surface of a tube according to claim 1, wherein the tube is simultaneously rotated while polishing the inner surface of the tube with the grinding brush. 10. The bristle block or bristle member is formed by collecting a predetermined amount of the thread-shaped or string-shaped bristle, and the bristle block or bristle member is loosely inserted into a shaft core or a grinding brush main body. The inner surface polishing apparatus for a pipe used in the method according to any one of claims 1 to 9, which is loosely fitted to the inner surface of the tube and is in expanded contact with the inner surface of the tube for polishing. 11. A bristle block loosely fitted to the grinding brush main body or a flocked grinding brush main body having bristles planted therein is divided into two or more pieces, which are enlargedly contacted with the inner surface of the pipe by a spring or the like. An inner surface polishing apparatus for a tube used in the method according to any one of claims 1 to 10, wherein the inner surface polishing apparatus is used for polishing. 12. A grinding brush is forcibly cooled or wet-processed by flowing a fluid such as air, water, oil, etc. into the rotary shaft in the pipe, or separately or simultaneously. An inner surface polishing apparatus for a pipe used in the method according to any one of claims 9 or 10 and 11.