JPH074664B2 - Vertical roll mill table recycling method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a technique relating to a device for operating a vertical roll mill on site, and, as a result, recovering a table surface in which wear and retreat occur, particularly on site.

[Prior Art] As a vertical mill, as shown in FIG. 4, a plurality of rollers that rotate on a horizontally rotating grinding table are urged so as to press against the upper surface of the table, and the object to be ground is ground in the grinding chamber. In general, it is charged from the upper part of the table, is drawn from the center of the table to the outer circumference by centrifugal force, is slid down between the roller and the table, is pulverized, and is extruded to the outside. Vertical type mills are widely used for coal, cement clinker, blast furnace slag, etc., and have a higher efficiency than drum type such as ball mills.

A problem with this type of milling condition is roller and table wear back. If the wear progresses evenly over the entire crushed surface, the relative relationship between the roller and the table is maintained, so there is little actual adverse effect, but in reality, both forms an uneven wear surface. As a result, the initially set crushing conditions have deteriorated significantly and the prescribed efficiency cannot be maintained.

FIG. 5 exemplifies this relationship. A crushing space C is formed between the roller R and the table T. The crushed product S is loaded from the right side of the figure and pushed out as powder P to the left side. While the process of continuing is continued, wear of both the roller and the tire progresses to become the A line. Of course, since the roller is urged downward by the trunnion mechanism, a predetermined gap can be maintained even if both surfaces retreat, so the grinding efficiency is not greatly affected during this range. However, when the operation continues to reach line B, the configuration of the crushing space C is reversed and the gaps on both sides that do not contribute to the crushing action become narrower, resulting in a noticeable deterioration in efficiency.

In order to prevent this, the inefficient roller is removed from the apparatus and replaced with a new spare part, or the circumferential surface of the roller is welded up and regenerated to restore the original crushing surface position. As a conventional technique focusing on this reproduction, there is, for example, Japanese Patent Publication No. 58-10143. Further, the applicant of the present invention has already made one proposal. (Japanese Patent Application Sho 63-6164
No. 3) [Problems to be solved by the invention] Due to the structure of the vertical roll mill, the rollers can be removed relatively easily, but it takes a lot of man-hours for the table.
Almost all of the dismantling work is difficult.
Therefore, if this disassembling and welding main work and assembling are added, the crushing work is interrupted for a long time, which exceeds the limit of the ultimate work place. As a next best measure, a liner made of wear-resistant metal (for example, high chrome cast iron) is fitted to the table base as shown in Fig. 4, and it is operated by leaving it to wear to limit the deterioration of grinding efficiency. After that, it is common to replace only the liner.

Upon further study, the vertical mill roller usually becomes a huge device, so it is difficult to manufacture the table as a single annular body, and the circumference is divided into multiple segments to be manufactured as a fan-shaped segment. , These are lined up locally to form an annular crushing surface. Naturally, some joints are formed at the joints between the segments, and abnormal joints, depressions or protrusions tend to be weak points in the crushing work, and the adverse effects of noise and vibration on the entire device have become a problem. When such a large size is used, it is not impossible to recycle the divided liner by hand welding, etc., but the number of man-hours for removing, welding, and installing the liner and the prolonged operation stop of the mill cannot be endured. Moreover, the crushed surface in which the segments that have been welded and regenerated are combined still has an adverse effect due to the joint seam, which is far from the solution of the problem.

Normally, vertical roller mills do not work independently, but share one of the entire flow as part of a plant that is combined before and after, so the crushing amount is reduced daily. However, if the properties of the powder deteriorate, the function of the entire plant will be significantly impaired.

In order to solve the problems described above, the present invention can easily and efficiently reproduce the wear and withdrawal range on the spot without removing the table of the vertical roller mill, and the crushing that occurs when the mill becomes large. It is an object of the present invention to provide a table regenerating device for a vertical roller mill that eliminates all the adverse effects attributable to surface division.

[Means for Solving the Problem] A table regenerating method for a vertical roll mill according to the present invention is
A portable disassembled automatic welding device, a table drive device to be regenerated, a control panel with a control function, a drive transmission member for temporarily replacing the original table drive device with the table drive device, and the work. The necessary tools and welding wire for the target material overlay are transported to the site where the vertical roll mill is installed, and the table drive device of the vertical roll mill that is currently connected is cut off from the middle and replaced with the drive device. , While controlling the table rotation speed with respect to the diametrical position of the table and the incidence angle of the welding torch with respect to the wear depth so that the optimum welding speed and welding posture are always maintained, the worn table surface is entirely covered in the field. The above-mentioned problems were solved by the procedure of recovery in the bed.

The apparatus used in the method includes a table drive device that can freely control the number of rotations of the portable state that has been disassembled, an automatic welding device, and a rotation speed for each revolution in cooperation with both devices. Control panel with a function for adjusting the table, a chain link for temporarily replacing the original table drive device with the table drive device, a drive transmission member such as a sprocket, tools necessary for the work, and a target material overlay. A combination of flux cord wires for welding or other welding wires is optimal.

[Operation] The original drive device (generally an electric motor, a motor shaft, a coupling, a reduction gear shaft, a reduction gear, a reduction gear,
Since the replacement is performed by inserting a separate drive device from the middle of the worm (rotary shaft), the rotation of the table is governed by the newly replaced drive device. This device allows the rotation speed to be adjusted freely, so that the torch at the fixed welding machine tip rotates the table so as to form a welding speed at which welding can be continued under the most favorable conditions. Generally, the table rotation speed during grinding action and the ideal welding speed (peripheral speed) are extremely different, and at the same rotation speed, the peripheral speeds on the inner and outer peripheral sides of the table are different. This overcomes the problem that it is difficult to achieve the ideal welding speed of the. That is, since the number of rotations decreases as the welding line progresses from the inner circumference to the outer circumference, the ideal welding condition once determined can be maintained from the beginning to the end.

On the other hand, the table wear is not uniform as described above, and the recessed depth usually draws a distorted curve, but the torch at the tip of the welding machine always follows the distorted curve to produce a predetermined electric arc. Follow to form. Due to the mechanism of the vertical roll mill, the retreat depth is almost constant in the circumferential direction.Therefore, the peripheral speed can be adjusted by changing the table speed when moving in the diametrical direction, and in the vertical direction. Adjustments to changes in the depth can be achieved by changing the posture of the torch and absorbing each to constantly maintain perfect welding conditions.

The automatic welding device used for this work, the drive device for rotating the table, the operation panel including these control devices, the predetermined tools, etc. are conveniently disassembled and stored, and are convenient to be transported from site to site. It is stored in a sturdy, functional box.

[Embodiment] FIGS. 1A and 1B are a front view (A) and a side view (B) showing a portion related to rotation control of a table in an embodiment of the present application.
The DC variable motor 1 is connected to the second reduction gear 4 again via the reduction gear 2 and the coupling 3 which are directly connected to each other, and transmits the sufficiently reduced rotation to the sprocket 5. The direct-current variable motor 1 can change in any range within 1:30 in order to form the most appropriate welding condition, and transmits the rotation from the sprocket 5 to the table rotary shaft of the vertical mill by a chain link. Alternatively, it is possible to use a combination of pulleys and belts.

Next, submerged arc welding is generally used for on-site welding on the table, but other processes that can be applied as fully automatic welding methods such as carbon dioxide welding and plasma arc welding are also possible. Is. In this example, the open arc welding method using a composite wire was adopted because of the simplicity of the equipment and the convenience of local construction. As the material of the table (liner), white pig iron containing 25% of chrome is the most well-known as a known wear-resistant material, so it is most desirable to restore the welded portion for overlay welding with almost the same material.

A flux cored wire was used in this example to identify the weld deposit with this material and still allow continuous automatic welding with the wire. That is, the wire shaft is hollow, and the hollow part is filled with powder of a desired additive component such as chrome or carbon, and the wire itself is made of a flexible material, and reacts at the time of welding to produce a component almost equal to the base metal. It is to be melted. If multiple welding heads are mounted and a structure that simultaneously generates an arc is mounted at the tip, the
It is most preferable because the amount of welding can be tripled.

An example of the control of the welding torch is shown in FIG.

In the figure, the torch 6 facing the wear retreat portion of the table T horizontally advances and retreats above the rack gear 7 that meshes with the lower bottom portion of the traveling beam 7. A carriage 8 and a fixed base 9 support the whole, and a wire feeding mechanism 10 is provided behind it.
There is. This feed mechanism mainly includes a wire feed motor 11, a wire feeder 12, and a wire straightener 13, and feeds the wire to the tip of the torch at a predetermined rate at a constant rate. The table T wears almost flatly and is not in a very distorted phase, so when the table makes one revolution and a single bead is placed on the entire circumference, the rack gear 7 operates and the tip of the torch becomes It moves forward to the center of the table by one bead and stops, and the bead for the next lap is placed again. In this case, the adjustment of the height of the torch tip is not so large, and it is usually sufficient for the operator to slightly adjust the height.

FIG. 3 shows another embodiment, which is an example in which the shape of the table T has a large arcuate crushing surface from the beginning, and the wear retreat surface also has a distorted curved surface. At this time, it is preferable to rotate the tip of the torch instead of moving the rack gear forward and backward in the previous example. In FIG. 3, the welding torch 6 and the wire feed mechanism 10 are fixed to a support base (not shown) by a support bar 14, and the wire feed mechanism as a whole can swing its head around a connection part suspended on the support bar. it can. Therefore, when one bead is welded by one rotation of the table,
The tilt angle of the tip of the torch is automatically (or manually) rotated by a desired angle to always maintain a posture facing the welding surface at a right angle. In order to support this, the wire conduit tube 15 is suspended in a hollow and bendable manner, and a constant amount of wire is always fed regardless of the rotation of the tip.

[Advantages of the Invention] Since the present invention has the configuration and operation described above, it enables the table to be regenerated in the field, which has been conventionally given up as impossible to construct, and restores an operating state similar to that of a new table. Moreover, since the construction days required for this purpose are extremely short, the sacrifice of stopping the operation of the mill can be reduced to a negligible level.

Furthermore, as if a single weld line formed a continuous weld line, like a needle groove on a record board, and filling the initial seam to form a flat and integrated crushing surface, it is necessary to use a new welding line at the time of installation. It should be said that the addition of preferable elements that surpass the table.

[Brief description of drawings]

1A and 1B are front and side views of the present embodiment (table drive control), FIG. 2 is a front view of the present embodiment (torch position control), and FIG. 3 is an embodiment different from the previous drawing. 4 is a front sectional view of a vertical roll mill, and FIG. 5 is a partial front sectional view for explaining the problems of the prior art. 1 ... DC variable motor, 2 ... reducer 3 ... coupling, 4 ... second reducer 5 ... sprocket, 6 ... torch 7 ... rack gear, 8 ... carriage 9 ... fixed base, 10: Wire feed mechanism 14: Support bar 15: Wire conduit tube S: Object to be crushed (raw material), P: Powder C: Grinding space, T: Table (liner) R: Roller

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toshio Yoshida 1-12-19 Kitahori, Nishi-ku, Osaka-shi, Osaka Prefecture Kurimoto Iron Works Co., Ltd. (72) Inventor Shigeaki Sugioka 1-12, Kithorie, Nishi-ku, Osaka-shi, Osaka No. 19 Kurimoto Iron Works Co., Ltd.

Claims (2)

[Claims] 1. A portable disassembled automatic welding device, a table drive device to be reproduced, an operation panel having a control function, and a drive transmission for temporarily replacing the original table drive device with the table drive device. The members, tools necessary for the work, welding wires for building up the target material, etc. were transported to the site where the vertical roll mill was installed, and the table drive device of the vertical roll mill currently connected was separated from the middle and transported. Replaced with the drive device, while controlling the rotation speed of the table with respect to the diametrical position of the table and the incident angle of the welding torch with respect to the wear depth so that the optimum welding speed and welding posture are always maintained, the worn table surface Table recovery method for a vertical roll mill, which is characterized in that the entire surface is recovered with a built-up layer. 2. A drive unit for a table, which can freely control the number of rotations of the portable unit, which is individually disassembled, and an automatic welding unit.
An operation panel having a function of adjusting the rotation speed for each revolution in cooperation with both devices, a drive transmission member for temporarily replacing the original table drive device with the table drive device, and a tool necessary for the work Table regenerator for a vertical roll mill characterized by comprising a welding wire for overlaying target materials.