JP4190465B2 - Internal polishing jig - Google Patents

Description

  In the present invention, for example, a plug is welded to close a through hole formed in a gas conduit made of a steel pipe whose inner surface is covered with a resin layer, or another pipe is joined to the through hole. The present invention relates to an inner surface polishing jig for removing a resin layer.

  For example, when a part of a gas conduit made of a steel pipe whose inner surface is coated with a resin layer is replaced or a branch pipe that is no longer needed is removed, as shown in FIG. A rubber ball 24 is inserted into the gas conduit 20 from the through hole 21 and inflated to cut off and remove the portion 23 to be replaced by blocking the gas. After a new pipe is joined to the removed portion, the rubber ball 24 is removed from the through hole 21, and a plug is attached to the through hole 21 and welded to be sealed.

  When a plug is attached to the through-hole 21 drilled in the gas conduit 20 and welding is performed, the resin layer 22 on the inner surface around the through-hole 21 is heated by welding heat and scattered in a mist form, and the scattered particles are dispersed in the gas conduit 20. It moves downstream with the gas flowing in. If these particles adhere to a downstream valve or gas device, there is a risk that the valve or gas device cannot be operated normally.

  In order to eliminate this danger, as shown in Patent Document 1, a plurality of one end portions of a polishing member, in which abrasive grains are fixed to a steel wire, are integrally fixed to a lower end portion of a hollow movable shaft. Abrasive unit is mounted in a radial and swingable manner, and from the lower end of this hollow movable shaft, a rotating shaft having a lower end fixed to the bottom of a cylindrical body having an opening at the top is inserted, and the abrasive of the hollow movable shaft is inserted. Use a polishing jig that inserts the unit mounting part inside the cylinder and switches the mounting angle of the steel wire constituting the abrasive to the hollow movable shaft according to the position of the abrasive unit mounting part with respect to the opening end of the cylinder is doing.

When inserting or removing this polishing jig from the through hole provided in the tube, insert the abrasive unit mounting part of the hollow movable shaft to the bottom of the cylinder, and fix the hollow movable shaft to the rotating shaft. The angle of attachment of the polishing member to the hollow movable shaft is reduced by the opening end of the cylindrical body, and the distance from the axis of the rotating shaft to the tip of the polishing member is made smaller than the radius of the through hole provided in the tube, Make sure that the tip of the wire does not touch the through hole. After inserting the polishing jig into the through hole provided in the tube, release the fixed of the hollow movable shaft to the rotating shaft, move the hollow movable shaft upward and move the fixed part of the polishing member to the vicinity of the opening end of the cylinder The angle of attachment of the polishing member, which is regulated by the opening end of the cylindrical body, to the hollow movable shaft is increased, and the distance from the axis of the rotating shaft to the tip of the polishing member is made larger than the radius of the through hole provided in the tube. The posture of the polishing member is changed so that the polishing member contacts the inner surface around the through hole. In this state, the rotation shaft is rotated, and the resin layer formed on the inner surface around the through hole is removed by rotating the polishing member while pressing the polishing member against the inner surface around the through hole. When removing this resin layer, the rotating shaft is pulled upward to increase the rotational radius of the tip of the polishing member, and the resin layer in a predetermined range is removed.
JP 2003-191159 A

  Since the steel wire having elasticity is used for the polishing member as described above, not only when removing the polishing jig from the through hole, but also when inserting the polishing jig into the through hole, the axis of the rotating shaft It is necessary to prevent the outer periphery of the through hole from being damaged by changing the position of the polishing member so that the distance to the tip of the polishing member becomes smaller than the radius of the through hole. It is necessary to change, and it takes time to change the position.

  Moreover, when removing the resin layer formed on the inner surface around the through-hole, the steel wire constituting the polishing member is pressed against the inner surface of the tube while rotating at high speed, so that the tip of the steel wire is deformed and polished. Even if the posture of the polishing member is changed when the jig is taken out from the through hole, the tip of the steel wire is caught on the outer peripheral portion of the through hole, and it is not easy to take out the polishing jig.

  The present invention provides an inner surface polishing jig that improves such disadvantages and can remove the resin layer around the inner surface around the through-hole formed in a gas conduit made of a steel pipe whose inner surface is coated with a resin layer with good workability. It is the purpose.

An inner surface polishing jig of the present invention is an inner surface polishing jig for removing a resin layer around an inner surface around a through-hole formed on a steel pipe whose inner surface is covered with a resin layer, and a cup brush attached to the tip of a rotating shaft, The cup brush has a housing, a compression spring, a holding cover, and a grip part. The cup brush fixes resin filaments made of polyamide resin containing abrasive grains and one end of many resin filaments along the outer periphery. And a holding portion that holds the resin filament radially so that the outer periphery of the tip portion of the resin filament is larger than the inner periphery of the through hole of the steel pipe , and the holding portion has an outer peripheral surface on the side opposite to the mounting portion of the resin filament. The housing is formed in a cylindrical shape and has an opening on one side, the cup brush is received from the holding portion side, and the compression spring is interposed between the bottom surface of the housing and the cup brush. Arrangement The force on the housing opening side is applied to the cup brush, the holding cover holds the cup brush in which the force of the compression spring is applied in the housing, the gripping part is formed of an elastic member, and the cup is attached to the tip. A plurality of holders having hooks that engage with connecting portions of the brush holding portion, are detachably attached to the bottom surface of the housing, are inserted into through holes formed in the steel pipe, and gradually rotate while rotating the rotating shaft. When pulled up, the tip of the radially spreading filament is pressed against the inner surface resin layer around the through hole while being rotated and polished. Hold the cup brush by engaging the hook of the holder of the gripping part with the groove, and hold the radially extended tip of the cup brush filament And pressed by the inner peripheral edge of the bar, characterized in that less than the diameter of the outer periphery of the through-hole of the tip of the filament.

  The cup brush may be detachably attached to the rotating shaft.

  When the polishing jig of the present invention is inserted into the through hole, the resin filaments radially attached to the holding portion of the cup brush have flexibility and elasticity. The brush can be easily inserted from the through hole.

  Also, when the resin filament is pressed against the inner surface around the through-hole while rotating the cup brush inserted from the through-hole, the resin filament has flexibility, so it bends along the inner surface around the through-hole and stably contacts, The inner surface around the through hole can be reliably polished by the abrasive grains contained in the resin filament.

  Further, when the polishing jig is taken out from the through hole, the cup brush is fixed to the bottom of the housing by a holding part having a plurality of holders formed of elastic members and having hooks. The holding jig is pressed by the inner peripheral end of the holding cover, and the outer periphery of the tip of the resin filament is made smaller than the diameter of the through hole, whereby the polishing jig can be easily pulled out from the through hole.

  In addition, by forming the resin filament of the cup brush with a polyamide resin having elasticity and wear resistance, when polishing the inner surface around the through-hole, it is stably contacted with the inner surface around the through-hole and polished with little wear. be able to.

  Furthermore, the used cup brush can be easily replaced with an unused cup brush by detachably attaching the grip portion to the bottom surface of the housing and detachably attaching the cup brush to the rotating shaft.

  FIG. 1 is a cross-sectional view showing a configuration of a polishing jig according to the present invention. As shown in the figure, the polishing jig 1 has a cup brush 3 attached to the tip of the rotating shaft 2, a housing 4, a compression spring 5, a holding cover 6, and a gripping part 7. The cup brush 3 has a polyamide resin filament 8 containing abrasive grains, and a brush holding portion 9 that fixes one end of a large number of filaments 8 along the outer periphery and holds them radially. The brush holding portion 9 is formed with a diameter that can be inserted into and withdrawn from, for example, a 40 mm through-hole, and a groove 10 having a constant width is provided on the outer peripheral surface on the opposite side of the fixing portion to which the filament 8 is fixed. It has the connection part 11 engaged with. The housing 4 is formed in a cylindrical shape and has an opening on one side, and accommodates the cup brush 3 from the brush holding portion 9 side. The compression spring 5 is disposed between the bottom surface of the housing 4 and the cup brush 3, and applies a force on the opening side of the housing 4 to the cup brush 3. The holding cover 6 holds the cup brush 3 in which the force of the compression spring 5 is acting in the housing 4. The gripping part 7 is formed of an elastic member, for example, a metal leaf spring or a resin such as polypropylene, polyamide resin, polyacetal, etc., and a plurality of holders 13 having hooks 12 at the tip, for example, as shown in the plan view of FIG. It has four or three, and is detachably attached to the bottom surface of the housing 4 with the holder 13 inside by means of mounting screws 14 and nuts 15.

  An operation when the inner surface resin layer 22 around the through-hole 21 drilled in the gas conduit 20 is removed using the polishing jig 1 will be described with reference to the process diagram of FIG.

  First, as shown in FIG. 3A, the polishing jig 1 is inserted into the through hole 21 formed in the gas conduit 20 from the housing 4 side. When the polishing jig 1 is inserted into the through hole 21, the tip end of the filament 8 that is radially attached to the brush holding portion 9 of the cup brush 3 extends larger than the diameter of the through hole 21, but the filament 8 is flexible. Therefore, the cup brush 3 can be easily inserted into the gas conduit 20 through the through hole 21. When the cup brush 3 is inserted into the gas conduit 20, as shown in FIG. 3 (b), the tip of the filament 8 spreads radially and expands larger than the diameter of the through hole 21. In this state, when the rotary shaft 2 is rotated to rotate the cup brush 10 and the rotary shaft 2 is gradually pulled up, the tip of the filament 8 is pressed against the inner surface resin layer 22 around the through hole 21 while rotating. The filament 8 whose tip is pressed against the inner surface resin layer 22 has flexibility and therefore bends following the inner surface resin layer 22 and stably contacts the inner surface resin layer 22, and is caused by the abrasive grains contained in the filament 8. The inner surface resin layer 22 is polished and removed. The pull-up amount of the rotating shaft 2 is adjusted so that the removal range of the inner surface resin layer 22 becomes a predetermined range. When the inner resin layer 22 is removed by polishing with the cup brush 3, the filament 8 of the cup brush 10 is made of a polyamide resin having wear resistance, so that the inner resin layer 22 can be removed with little wear. it can.

  When the inner surface resin layer 22 is removed to a predetermined removal range, the rotation of the rotating shaft 2 is stopped and the rotating shaft 2 is pushed into the gas conduit 20. When the rotary shaft 2 is pushed into the gas conduit 20, the housing 4 is lowered, and the bottom of the housing 4 abuts against the inner surface of the pipe opposite to the through hole 21. When the rotary shaft 2 is further pushed in, as shown in the sectional view of FIG. 4, the cup brush 3 pressed against the holding cover 6 side by the compression spring 5 is pushed into the housing 4, and the brush holding portion 9 of the cup brush 3. The connecting portion 12 provided in the holder 13 enters the holder 13 of the gripping portion 7 attached to the floor surface of the housing 4, and the groove 11 provided in the connecting portion 12 engages with the hook 12 provided at the tip of the holder 13, The cup brush 3 is held by the holder 13. At this time, the radially extending tip of the filament 8 of the cup brush 10 is held by the inner peripheral end of the holding cover 6, and the outer periphery of the filament 8 is smaller than the diameter of the through hole 21. In this state, the cup brush 3 and the housing 4 can be easily pulled out from the through hole 21 by pulling up the rotary shaft 2.

  After the polishing jig 1 is pulled out from the through-hole 21, the nut 15 that fixes the grip 7 that holds the cup brush 3 to the housing 4 is taken out, and the cup brush 3 and the cup brush 3 are held from the housing 4. The holding portion 7 is removed from the housing 4 and the used cup brush 3 is removed from the holding portion 7. Thereafter, the grip portion 7 is attached to the housing 4, the used cup brush 3 attached to the rotary shaft 2 is replaced with an unused cup brush 3, and the next through hole 21 is processed. In this way, the used cup brush 3 can be easily replaced.

  In the above description, the case where the inner surface resin layer 22 around the through hole 21 drilled in the gas conduit 20 with the polishing jig 1 is removed has been described. However, the foreign matter adhered to the inner surface of the surroundings such as the through holes and flanges of various containers. The same can be applied to the removal polishing.

It is sectional drawing which shows the structure of the grinding | polishing jig | tool of this invention. It is a top view which shows the structure of a holding part. It is process drawing which shows the usage method of a grinding | polishing jig | tool. It is sectional drawing which shows a state when pulling out a grinding | polishing jig | tool from a through-hole. It is sectional drawing which shows the gas interruption | blocking state when replacing a part of gas conduit.

Explanation of symbols

1; polishing jig, 2; rotating shaft, 3; cup brush, 4; housing, 5; compression spring,
6; holding cover, 7; gripping part, 8; filament, 9; brush holding part,
10; groove, 11; connecting portion, 12; hook, 13; holder, 14; mounting screw,
15; Nut, 20; Gas conduit, 21; Through hole, 22; Inner surface resin layer.

Claims (2)

An inner surface polishing jig for removing the resin layer on the inner surface around the through hole formed on the steel pipe whose inner surface is coated with the resin layer,
A cup brush attached to the tip of the rotating shaft, a housing, a compression spring, a holding cover and a gripping portion;
The cup brush fixes resin filaments made of polyamide resin containing abrasive grains and one end of many resin filaments along the outer periphery, and the outer periphery of the tip of the resin filament penetrates the steel pipe. It has a holding part that holds radially so as to be larger than the inner periphery of the hole , and the holding part has a connecting part having a groove with a constant width on the outer peripheral surface on the side opposite to the mounting part of the resin filament,
The housing is formed in a cylindrical shape, has an opening on one side, accommodates the cup brush from the holding portion side,
The compression spring is disposed between the bottom surface of the housing and the cup brush, and applies a force on the housing opening side to the cup brush,
The holding cover holds the cup brush in which the force of the compression spring is acting in the housing,
The grip portion is formed of an elastic member, and has a plurality of holders having hooks that engage with a connection portion of the cup brush holding portion at the tip, and is detachably attached to the bottom surface of the housing .
When inserted into the through-hole formed in the steel pipe and gradually lifted while rotating the rotating shaft, the tip of the radially spreading filament is pressed against the inner surface resin layer around the through-hole and polished, and a cup brush Is pushed into the housing, the cup brush is held radially by engaging the hook of the holder of the gripping part with the groove provided in the connecting part of the holding part of the cup brush, and the filament of the cup brush spreads radially. An inner surface polishing jig characterized in that the tip end is pressed by the inner peripheral end of the holding cover and the outer periphery of the tip end of the filament is made smaller than the diameter of the through hole . The internal polishing jig according to claim 1, wherein the cup brush is detachably attached to a rotating shaft.

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