JPH06101973A - Deterioration diagnostic method for rotary kiln tire or supporting roller and deterioration recovery method - Google Patents

Abstract

PURPOSE:To diagnose a progressing state of deterioration of a tire of a rotary kiln and a supporting roller before cracks or separation appear on the surface of a rolling part and recover the deterioration and thereby prolong the service life. CONSTITUTION:The hardness of a rolling face 2a of a tire 2 of a rotary kiln 1 and a rolling face 4a of a support roller 4 after the start of their application is measured. The measured hardness is compared with the limit hardness which can generate cracking or separation on the rolling faces 2a and 4a. The more the measured hardness approaches the limit hardness, it is diagnosed that the more deteriorated the hardness is. If the rolling faces 2a and 4a are heated for a specific time, it will be possible to recover the deterioration and prolong their service life.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deterioration diagnosis method and a deterioration recovery method for a tire or a support roller of a rotary kiln.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show a general support structure of a rotary kiln for firing cement or the like.
The rotary kiln 1 of this type has a plurality of tires 2, which are fitted on each other at required intervals in the longitudinal direction, and are arranged to face each other on both sides in the width direction of each bed 3 provided corresponding to the position of the tire 2. It is supported by a pair of support rollers 4 and 4, and is rotationally driven by an electric motor 5 via a speed reducer 6, a main pinion 7, a girth gear 8 and the like.

Therefore, the tire 2 and the support roller 4 rotate while receiving the load of the rotary kiln 1, and stress is repeatedly applied to the contact point between the tire 2 and the support roller 4 during operation. Therefore, the tire 2 and the support roller 4 were cracked or peeled due to aged deterioration on the rolling surfaces 2a and 4a while the tire 2 and the support roller 4 were continuously operated.

The cracks and peeling phenomena that occur on the rolling surfaces 2a, 4a of the tire 2 and the support roller 4 do not hinder the operation in the initial stage, but when the cracks and peeling phenomena progress, the tire 2 In addition, the support roller 4 may be broken or broken, and the rotary kiln 1 may not be operated.

Therefore, conventionally, when cracks or peeling occur on the rolling surfaces 2a, 4a of the tire 2 and the support roller 4, the locations where the cracks or peeling occur are removed and repaired by welding or the like. , If there is a margin in strength,
Rolling surfaces 2a, 4a of the tire 2 and the support roller 4
Was cut by a lathe or the like to remove cracks and peeling depths.

[0006]

However, cracks and peeling generated on the rolling surfaces 2a, 4a of the tire 2 and the support roller 4 are not always used because of different design conditions and operating conditions on the user side. Since it is not a phenomenon that the occurrence time can be judged from the time lapse from the start or the cumulative number of rotations, it is difficult to predict the occurrence time of the crack or peeling, and it is confirmed that the crack or peeling is a visible phenomenon. The current situation is that we will begin to consider repairs and replacements only when we are able to do so.

Therefore, there has been a problem that preparation for repair or replacement is delayed, and an idle period for stopping the operation of the rotary kiln 1 for repair or replacement becomes long.

[0008] In particular, when it is necessary to replace the tire, the tire 2 and the support roller 4 are castings, so it is difficult to manufacture a new replacement article in a short period of time. Was getting longer.

Further, as described above, if it is difficult to predict the timing of occurrence of cracks or peeling, there is no room to make production adjustments, and there is a problem that the production schedule is changed due to an unscheduled stop of operation.

The present invention has been made in view of the above-mentioned circumstances, and a tire of a rotary kiln capable of diagnosing the progress of deterioration of a tire or a support roller of a rotary kiln before cracks or separation occur on a rolling surface or It is an object of the present invention to provide a deterioration diagnosis method for a support roller and a deterioration recovery method capable of extending the life by recovering the deterioration at a suitable time by the deterioration diagnosis method.

[0011]

According to the present invention, the hardness of the rolling surface of a rotary kiln tire or support roller after the start of use is measured, and the measured hardness causes cracking or peeling of the rolling surface. A method for diagnosing deterioration of a tire or a support roller of a rotary kiln, characterized by diagnosing that deterioration of the rolling surface is progressing as the measured hardness is closer to the limit hardness as compared with the limit hardness. The critical hardness was set to about 300 Hv, and a deterioration diagnosis method for a tire or support roller of a rotary kiln, and a hardness of a rolling surface after the use of the tire or support roller of the rotary kiln was measured, and the measurement was performed. The hardness is compared with the critical hardness at which cracking or peeling occurs on the rolling surface, and when the measured hardness approaches the critical hardness, the rolling surface is heated for a predetermined time to soften. Those relating to the deterioration recovery method of the tire or support rollers of the rotary kiln, characterized in Rukoto.

[0012]

Therefore, in the present invention, the hardness of the rolling surface after the start of use of the tire or support roller of the rotary kiln is measured, and the measured hardness is compared with the critical hardness at which the rolling surface is cracked or peeled. This makes it possible to diagnose the progress of deterioration of the rolling surface before cracks or peeling occur. Furthermore, by heating and softening the rolling surface when the hardness measured with respect to the critical hardness becomes low, it is possible to recover the deterioration of the rolling surface before cracks or peeling occur.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention. In the following description, FIGS. 3 and 4 will be referred to for the rotary kiln, tires, and support rollers.

The inventor of the present invention investigates the rolling surfaces 2a, 4a of the tire 2 and the support roller 4 in which cracks and peeling have occurred, and in addition to the visible phenomenon such as cracks and peeling, the rolling surface 2a. , 4a was examined for any change, and the fact that the hardness of the rolling surfaces 2a, 4a was harder than that at the start of use was confirmed.

Therefore, the hardness of the rolling surfaces 2a, 4a of the tire 2 and the support roller 4 of the rotary kiln 1 is periodically measured from the start of operation using a portable hardness meter, and the rolling surfaces 2a, 4a are measured. As a result of collecting data until cracks and peeling occur, for example, in the case of the tire 2 made of chrome manganese steel, as shown in FIG. 1, the hardness of the rolling surface 2a increases as the cumulative number of rotations increases. And about 300 Hv
It was confirmed that many cracks and peeling were observed in the hardness region exceeding the above range, and almost no cracks or peeling were observed in the hardness region below this range.

The tendency shown in FIG. 1 described above is similarly confirmed in the tire 2 and the support roller 4 made of other heat-resistant steel materials such as chrome molybdenum steel and carbon steel cast steel. Although there is a slight difference in the degree of change in hardness, the critical hardness at which cracks and peeling occur on the rolling surfaces 2a, 4a is about 30 for all heat-resistant steel materials.
It was 0 Hv.

Therefore, a hardness region of 300 Hv or more is regarded as a dangerous region, and the hardness of 2 is slightly lower than 300 Hv.
The hardness range up to 80 Hv is the preventive range, and
If the hardness region equal to or less than v is a safety region, the rolling surfaces 2a, 4a of the tire 2 and the support roller 4 of the rotary kiln 1
By measuring the hardness of the rolling surface 2a, 4a
It is possible to confirm in which region the progressing state of deterioration is present, and if the measured hardness is in the preventive region, it is diagnosed that the occurrence of cracks and peeling is near, that is, the deterioration state is progressing considerably. It becomes possible to do.

As described above, the rolling surface 2 after the use of the tire 2 and the support roller 4 of the rotary kiln 1 is started.
By measuring the hardness of a and 4a, the rolling surface 2
Since the progress of deterioration of a and 4a can be diagnosed before cracks or peeling occur, it is possible to predict the time of repair or replacement work and prepare with a margin. The idle period of the rotary kiln 1 can be significantly shortened as compared with the conventional one, and production adjustment can be performed in preparation for the repair or replacement work.

Further, if the progress of deterioration of the tire 2 and the support roller 4 of the rotary kiln 1 can be diagnosed before cracks or peeling occur on the rolling surfaces 2a, 4a, the measured hardness becomes a preventive area. In such a case, the rolling surfaces 2a, 4a of the cured tire 2 and the support roller 4 are heated by a gas burner or an electric resistor for a predetermined time to be softened, thereby extending the life of the tire 2 and the support roller 4. It can also be planned.

The data on the change in hardness due to heating of the rolling surfaces 2a, 4a are as shown in FIG. 2, and this data is an example in which the tire 2 made of chrome manganese steel is heated for 2 hours.

The deterioration diagnosing method and the deterioration recovering method of the tire or the support roller of the rotary kiln according to the present invention are not limited to the above-mentioned embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it is possible to add.

[0023]

According to the above-described deterioration diagnosis method and deterioration recovery method of the tire or support roller of the rotary kiln of the present invention, various excellent effects as described below can be obtained.

(I) Diagnosing the progress of deterioration of the rolling surface before cracking or peeling by measuring the hardness of the rolling surface after the use of the tire and support roller of the rotary kiln. You can

(II) According to the above (I), it is possible to predict the time of repair or replacement work and prepare with a margin, and the idle period of the rotary kiln during the repair or replacement work can be shortened to a great extent compared to the conventional case. be able to.

(III) According to the above (I), production adjustment can be performed in preparation for repair or replacement work.

(IV) According to the above (I), the rolling surface of the cured tire and the support roller is softened by heating for a predetermined time at a suitable time before cracking or peeling occurs on the rolling surface, whereby the above It is possible to prolong the life of the tire and the support roller, and it is possible to eliminate the troublesome cutting work of the rolling surface.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the cumulative number of rotations of a rolling surface and changes in hardness and occurrence of cracks and peeling in one example of the present invention.

FIG. 2 is a graph showing a hardness change due to heating of a rolling surface in an example of the present invention.

FIG. 3 is a perspective view showing a general support structure of a rotary kiln.

FIG. 4 is a view in the direction of arrows IV-IV in FIG.

[Explanation of symbols]

 1 rotary kiln 2 tire 2a rolling surface 4 support roller 4a rolling surface

Claims (3)

[Claims] 1. The hardness of a rolling surface of a rotary kiln tire or a support roller after the start of use is measured, and the measured hardness is compared with a critical hardness at which cracking or peeling occurs on the rolling surface, A deterioration diagnosing method for a tire or a support roller of a rotary kiln, comprising diagnosing that deterioration of the rolling surface is progressing as the measured hardness is closer to the hardness. 2. The method for diagnosing deterioration of a tire or a support roller of a rotary kiln according to claim 1, wherein the limit hardness is about 300 Hv. 3. The hardness of a rolling surface of a rotary kiln tire or a support roller after the start of use is measured, and the measured hardness is compared with a critical hardness at which cracks or peeling occur on the rolling surface, A method for recovering deterioration of a tire or a support roller of a rotary kiln, wherein the rolling surface is heated and softened for a predetermined time when the measured hardness becomes close to the hardness.