JP2000127051A - Wet polishing roll for round pipe outer face - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a round pipe reducing the slip between the round pipe and rolls and having uniform polished surface quality in a wet grinding wheel polishing centerless round pipe feed device. SOLUTION: A rubber lining 13 dispersed with a base material rubber 11 and granular rubbers 12 having a hardness difference is provided on each roll peripheral face of the rotary roll, feed roll and presser roll of a centerless feed device, and single or multiple grooves 15 inclined relative to the roll width direction are formed. The roll peripheral face has the hardness difference and the grooves 15 for discharging an abrasive liquid, the slip between the rolls and a round pipe is prevented, and the round pipe is polished by a wet grinding wheel under a stable condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll such as a rotary roll, a feed roll, and a press roll used for wet-polishing the surface of a round pipe using a grindstone while feeding the round pipe by a centerless feeder.

[0002]

2. Description of the Related Art The outer surface of a round pipe is usually dry-polished using flap holes, but wet polishing is also known. However, although the wet grinding wheel can obtain high grinding power, it has poor followability to the undulation of the outer surface of the round pipe,
Not widely used because the outer surface cannot be polished uniformly. The followability of the wet grinding wheel is improved by elastically pressing the wet grinding wheel against the outer surface of the round pipe. For example, Japanese Patent Application Laid-Open Nos. 9-67442 and 10-2
No. 4873, etc., a spring that can expand and contract in the direction of the rotation axis is interposed between the metal pedestal to which the grinding wheel is fixed and the flange to which the rotation shaft is fixed, and the air pressure that presses the grinding wheel against the outer surface of the round pipe is further reduced. By controlling, the grinding wheel follows the undulation in the circumferential direction of the outer surface of the round pipe.

[0003]

For the outer surface polishing by the wet grinding wheel polishing method, the centerless pipe feeding method for continuously feeding round pipes is more efficient than the batch method for polishing while fixing both ends of round pipes in consideration of production efficiency. It is advantageous. But,
In the case of wet polishing using a centerless pipe feed method, the applied polishing liquid lowers the frictional force between the round pipe and the roll, causing slip, and the rotation and feed of the round pipe tend to be unstable. In addition, when polishing by rotating the grindstone in the direction opposite to the rotation direction of the round pipe, the amount of grinding increases, and polishing with a smaller number of heads of polishing equipment becomes possible, but since the rotation directions are opposed to each other. A force that hinders rotation of the round pipe acts, and rotation and feeding of the round pipe become unstable.

Generally, the frictional force between the outer surface of a round pipe and a roll increases in accordance with the surface roughness of the round pipe.
The rougher the surface, the smoother the rotation of the round pipe and roll. However, when the grindstone and the round pipe are rotated in directions opposite to each other in the rough polishing using a grindstone having a small grinding number, the resistance for suppressing the rotation of the round pipe becomes very large. When the resistance exceeds the rotational force given to the round pipe, the round pipe slips, and the rotation of the round pipe may temporarily stop.

On the other hand, when the grindstone and the round pipe are rotated in opposite directions in the finish polishing using a grindstone having a large grinding number, the resistance of the grindstone for suppressing the rotation of the round pipe is much larger than the resistance during rough polishing. Small. However, because the surface roughness of the round pipe to be polished is small,
Slippage easily occurs between the roll and the round pipe due to the lubrication effect of the polishing liquid. Above all, in the case of a round pipe having a small surface roughness and a mirror surface, the frictional force between the roll and the round pipe that gives the rotational force is also reduced, so that the round pipe is more likely to slip. It is indispensable for the round pipe to be polished to rotate under stable conditions in order to obtain a uniform polished surface quality, but in actual wet polishing using a grindstone, the rotation of the round pipe is irregular as described above. Easy to fluctuate. As a result, a difference occurs in the amount of grinding corresponding to the fluctuation of the rotation speed in the circumferential direction of the round pipe, and it is difficult to obtain uniform polished surface quality.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been devised to solve such a problem, and has a rubber lining layer in which granular rubber having a difference in hardness is provided and which is inclined in the roll width direction. It is an object of the present invention to provide a wet grinding wheel polishing roll that prevents slippage between a round pipe and a roll by providing a groove, and stabilizes rotation and feeding of the round pipe to make the polishing surface quality uniform. . The roll of the present invention
Used as a rotating roll, feed roll, presser roll, etc. in wet grindstone polishing, a rubber lining in which granular rubber with a hardness difference is dispersed between the base rubber and the rubber lining is provided on the roll peripheral surface, and a single piece sloping in the roll width direction Alternatively, a plurality of grooves are formed in the rubber lining. The difference in hardness between the granular rubber and the base rubber is preferably in the range of 5 to 20 in Shore hardness. The amount of the granular rubber relative to the base rubber is preferably in the range of 10 to 40% by weight. The inclination angle of the groove with respect to the roll width direction is preferably in the range of 10 to 50 degrees. The total opening area of the groove preferably occupies 10 to 50% of the roll surface area.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a centerless type round pipe outer surface polishing apparatus, for example, as shown in the plan view of FIG.
A feed device having a feed roll 2 and a press roll 3 is used. Rotating roll 1, feed roll 2, presser roll 3
Is in contact with the outer surface of the round pipe P, as shown in FIG. The individual rotating rolls 1 are connected to each other by a rotating roll shaft 4 with the rotating shaft coinciding with the tube axis direction of the round pipe P, and rotate in the same direction at the same speed. The rotation axis of the feed roll 2 is inclined in the pipe axis direction of the round pipe P, and a running force is given to the round pipe P by the inclination angle and the rotation of the round pipe P.
The presser roll 3 is arranged to be inclined in the pipe axis direction of the round pipe P as necessary, and prevents the round pipe P rotating and running from floating.

As shown in FIG. 3, the grindstone 5 for polishing the outer surface of the round pipe P is pressed against the outer surface of the round pipe P at a constant pressure by a rotary pressurizing means 6 and rotates at a constant speed. A polishing liquid 8 is supplied from a nozzle 7 to the outer surface of the round pipe P that is in contact with the grinding surface of the grindstone 5. In the present invention, as a rotary roll 1, a feed roll 2, and a press roll 3, a rubber lining 13 formed by dispersing a granular rubber 12 in a base rubber 11 and integrally forming the same as shown in FIG. ing. The base rubber 11 and the granular rubber 12 are selected from urethane rubber, hypalon rubber, synthetic rubber, and the like so that a difference in hardness occurs between the two. Since there is a difference in hardness between the base rubber 11 and the granular rubber 12, a stress distribution corresponding to the difference in hardness is generated in the rubber lining 13 in contact with the round pipe P. That is, the pressing force is intensively increased in the hard portion of the rubber lining 13, and the frictional force between the roll 10 and the round pipe P is increased. As a result, slip of the round pipe P is prevented.

Either the base rubber 11 or the granular rubber 12 may be hard. However, the hardness difference between the two is preferably in the range of 5 to 20 in Shore hardness in consideration of wear resistance, frictional force between the roll 10 and the round pipe P, and the like.
When the hardness difference is less than 5, the slip prevention effect tends to decrease. Conversely, if the hardness difference exceeds 20, the base rubber 11 or the granular rubber 12 will be significantly worn, or marking will easily occur on the outer surface of the round pipe P. The compounding amount of the granular rubber 12 is preferably set in the range of 10 to 40% by weight in consideration of abrasion resistance, frictional force between the roll 10 and the round pipe P, and the like. When the amount is less than 10% by weight or more than 40% by weight, the slip suppressing force due to the difference in hardness becomes small.

In the wet grinding stone polishing, the outer surface of the round pipe P is polished while supplying the polishing liquid 8. The polishing liquid 8 cools the round pipe P, the grindstone 5, etc., which have been heated by the frictional heat generated during polishing, clogs the working surface of the grindstone 5, polish debris on the outer surface of the round pipe P and the working surface of the grindstone 5. Has the effect of preventing welding. In this regard, a large supply of the polishing liquid 8 is advantageous. However, the supplied polishing liquid 8 contains the roll 10 and the round pipe P
It is likely to stay between them, causing slip to occur. Therefore, it is necessary to effectively remove the polishing liquid 8 from between the outer surface of the round pipe P and the peripheral surface of the roll 10 to prevent slip. As a removing means of the polishing liquid 8, a method of blowing off the polishing liquid 8 adhered by blowing air to the outer surface of the round pipe P can be considered. However, in a feeding device in which a large number of rotary rolls 1, feed rolls 2, and press rolls 3 are arranged, it is necessary to provide air blowing means in accordance with the number of rolls, resulting in an increase in equipment costs. Further, there is a possibility that the polishing liquid 8 blown off from the outer surface of the round pipe P scatters around and deteriorates the working environment.

Therefore, the present invention employs a method in which a groove 15 is formed in the rubber lining 13 and the polishing liquid 8 flows out through the groove 15. When the roll 10 is pressed against the round pipe P, the rubber lining 13 receives a reaction force and is compressed. At this time, the rubber lining 13 is not uniformly compressed, and the thickness after compression changes according to the difference in hardness between the base rubber 11 and the granular rubber 12. That is, the rubber lining 13 in the compressed state has a surface having concave portions and convex portions corresponding to the hardness difference. Therefore, the polishing liquid 8 existing between the rubber lining 13 and the outer surface of the round pipe P flows into the groove 15 via the concave portion, and is discharged outside from the contact area between the roll 10 and the round pipe P.

The angle θ of the groove 15 with respect to the roll width direction is
It is preferable to set the angle in the range of 10 to 50 degrees. Groove angle θ
Is less than 10 degrees, that is, when the direction of the groove 15 is close to the roll width direction, the circumferential surface of the round pipe P tends to partially contact the roll 10. As a result, the difference between the surface portion with the groove 15 and the surface portion without the groove 15 causes the round pipe P
The impact applied to the round pipe P is also increased, and vibration that destabilizes polishing conditions is also applied to the round pipe P. Conversely, when the groove angle θ exceeds 50 degrees, that is, when the direction of the groove 15 approaches the circumferential direction of the roll 10, the ratio of the surface of the roll 10 continuously contacting the outer surface of the round pipe P increases.
The effect of discharging the polishing liquid 8 due to 5 becomes weaker. The total area ratio of the opening of the groove 15 occupying the roll peripheral surface is set in the range of 10 to 50% in consideration of the discharge action of the polishing liquid 8 by the groove 15, the influence of the groove 15 on the vibration to the round pipe P, and the like. Is preferred. At an opening total area ratio of less than 10%, the groove 1
5 is filled with the polishing liquid 8 in a short time, and the round pipe P easily slips. Conversely, if the total area ratio of the openings exceeds 50%, the round pipe P fits into the groove 15 and marking is likely to occur on the outer surface of the round pipe P.

As described above, the roll 10 having the rubber lining 13 in which the grooves 15 are formed with a difference in hardness due to the dispersion of the granular rubber 12 can provide the round pipe P without giving vibrations that adversely affect polishing to the round pipe P. Outer surface and roll 10
This has the function of discharging the polishing liquid 8 that tends to stay on the contact surface with the polishing liquid. Therefore, when the roll 10 is used for the rotary roll 1, the feed roll 2, the presser roll 3 and the like in the feed device for wet grinding stone polishing, the round pipe P is polished in a stable state without slip, so that the polished surface quality is kept constant. Is done.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a material to be polished, an outer diameter of 50.8 mm and a thickness of 1.
Using a SUS304 stainless steel round pipe having a length of 5 mm and a length of 500 mm, wet grinding was performed by a centerless round pipe feed system. At this time, the resin bond grindstone GC
# 220, resin bond whetstone GC # 80 for finish polishing
0, and the polishing conditions shown in Table 1 were employed.

[0015]

The centerless round pipe feeder has a diameter of 8 mm.
Rolls having a length of 0 mm and a body length of 40 mm were used as a rotating roll 1, a feed roll 2, and a press roll 3. The rotating roll 1 includes a urethane rubber base rubber 11 having a Shore hardness of 80 and a urethane rubber granular rubber 1 having a Shore hardness of 85 and 110, respectively.
A rubber lining 13 having a thickness of 15 mm in which 2 is dispersed by 20% by weight is provided on the peripheral surface of the roll.
A groove 15 was formed in the rubber lining 13 at 50 degrees and a total opening area ratio of 10 to 50%. 50 commercial water-soluble grinding fluids
A polishing liquid 8 was prepared by diluting the polishing liquid 8 times, and the polishing liquid 8 was supplied at a flow rate of 0.0
While supplying at 5 m ³ / min, the round pipe P is rotated at a peripheral speed of 80
m / min at a feed rate of 4 m / min. The outer surface of the polished round pipe P was observed, and the effects of the groove angle θ and the ratio of the total area of the openings on the slip were investigated. As can be seen from the investigation results in Table 2, the groove 15 under the conditions specified in the present invention.
In the pipe feeder using the rotary roll 1 having the rubber lining 13 formed with the above, no slip was detected on the outer surface of the polished round pipe P, and the polished surface quality was uniform.

[0017]

Hardness difference Δ between base rubber 11 and granular rubber 12
The round pipe P was polished under the same conditions as in the example using a rotating roll in which the conditions of the HV and the groove 15 were changed. The surface of the polished round pipe P was observed, and the effects of the hardness difference ΔHV, the inclination angle θ of the groove 15 and the area ratio on the occurrence of slip were investigated. As can be seen from the survey results in Table 3, the hardness difference ΔH
In Test Nos. 9 to 11 without V, slip occurred regardless of the inclination angle θ and the area ratio of the groove 15, and slip occurred in Test Nos. 12 to 14 without the groove 15 even if there was a hardness difference ΔHV. And the round pipe P
The rotation and feeding of the rags became irregular, resulting in a non-uniform polished surface.

[0019]

In the above description, the present invention is applied to the rotary roll 1, but the same effect can be obtained by applying the present invention to the feed roll 2 and the press roll 3.

[0021]

As described above, the roll of the present invention is provided with a rubber lining integrally formed by blending granular rubber having a hardness difference with the base rubber on the roll peripheral surface, and further in the roll width direction. Since it forms a groove inclined to
A hardness difference where the frictional force acts intensively is attached to the roll surface,
Moreover, the polishing liquid is effectively discharged from the outer surface of the round pipe and the peripheral surface of the roll via the groove. In this way, when the roll according to the present invention is used as a rotating roll, a feed roll, a presser roll, etc. in a centerless feeder of a wet-type grindstone polishing device, the occurrence of slip is suppressed, and the round pipe is polished under stable conditions. A product having a uniform polished surface quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view showing the overall configuration of a centerless feeder.

FIG. 2 is a side view showing a positional relationship between a rotary pipe, a feed roll, a presser roll, and a round pipe.

Fig. 3 Wet wheel grinding machine for round pipe with centerless feeder

FIG. 4 shows a roll provided with a rubber lining according to the invention.

[Explanation of symbols]

1: rotating roll 2: feed roll 3: holding roll 4: rotating roll shaft 5: whetstone 6: rotating pressurizing means 7: nozzle 8:
Polishing liquid 10: Roll 11: Base rubber 12: Granular rubber
13: rubber lining 14: roll body 15: groove θ: inclination angle of groove with respect to roll width direction P: round pipe (material to be polished)

Continuing from the front page (72) Koji Enoki 1 Tsurumachi, Amagasaki-shi, Hyogo Pref. Nisshin Steel Co., Ltd. (72) Inventor Shigeo Matsubara 1 Tsurucho, Amagasaki-shi, Hyogo Nisshin Steel Co., Ltd. F term (reference) 3C063 AA02 AB03 BA24 BB01 BC04 EE11

Claims (1)

[Claims] 1. A rubber lining in which granular rubber having a hardness difference with a base rubber is dispersed is provided on a peripheral surface of a roll, and one or more grooves inclined in a roll width direction are formed in the rubber lining. Roll for polishing the wet grindstone on the outer surface of a round pipe.