JPH0815237A - Roll flaw detecting method - Google Patents

Abstract

PURPOSE:To enable flaw detection on the whole surface of a roll efficiently and correctly by shifting the phase in the circumferential direction of a roll corresponding to a flaw detectable width at every path by plural pulses of finishing to perform flaw detection. CONSTITUTION:When flaw detection is made once round a roll in the axial direction of the roll at the final one path, flaw detection is made at certain intervals of the flaw detectable width. Accordingly, if the phase of the next second path is controlled to be shifted, the nest phase to flaw detection on the first orbit is subjected to flaw detection. Further, a part not subjected to flaw detection is again shifted in phase, and flaw detection at the third path is made in the circumferential direction of the roll. thus, when the final plural paths in the whole N-paths of finishing are subjected to flaw detection while the maximum feed speed determined by the flaw detectable width is taken and the phase in the circumferential direction of the roll is controlled to be shifted corresponding to the flaw detectable width at each path, flaw detection for the whole surface of the roll can be accomplished after N-paths. Thus, flaw detection for the whole surface of the roll can be completed simultaneously with finishing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll flaw detection method in the final pass of finish grinding of a roll.

[0002]

2. Description of the Related Art In hot rolling, roll damage, particularly work roll wear and roughening, affects the surface properties of rolled products, quality such as plate crown, and shape.
The detection of roll damage has become a very important issue as the load increases and the rolling speed increases due to recent advances in rolling technology. As a current inspection method, a method of detecting a product defect by visually inspecting the surface of the rolled product or by an eddy current sensor or the like is used. However, in such a method, roll damage occurs, and as a result, the product quality is deteriorated and can be detected, and all rolled products become defective until it is detected. Will bring.

In order to solve such a point, for example, an AE wave detector is arranged on a roll, and an AE wave which is an elastic wave generated by cracks, abrasion or energy release of plate flaws generated on the roll surface during rolling is applied. It has been attempted to detect and detect damage to the roll at an early stage, and it is known that the flaws detected by these detect the surface texture by roll grinding.

[0004]

However, in the conventional roll grinding, in order to improve the work efficiency, as finishing grinding, mainly grinding for adjusting only the surface texture is performed, and usually a plurality of passes are carried out at the end of grinding. However, roll flaw detection may be performed simultaneously on this final pass. In this case, if you try to detect flaws on the entire surface of the roll,
Since the maximum value of the axial relative speed between the grinding wheel and the roll is determined by the flaw detection width constraint, the effect of improving the work efficiency is small. That is, since the flaw detection speed is lower than the grinding feed speed, there is a problem that the work efficiency deteriorates.

[0005]

[Means for Solving the Problems] As a result of intensive development, the inventors of the present invention should solve the above-mentioned problems, and as a result, roll flaw detection is performed on a plurality of passes for finish grinding while shifting the phase in the roll circumferential direction for each pass. The purpose is to provide a roll flaw detection method that achieves flaw detection on the entire surface of a roll. The gist of the invention is that in a roll flaw detection method in the final pass of finish grinding of a roll, roll flaw detection is performed in a plurality of passes of finish grinding, and phase control is performed to shift the phase in the roll circumferential direction for each pass by an amount equivalent to the flaw detection width. The roll flaw detection method is characterized in that the flaw detection is performed by performing the flaw detection.

[0006]

The present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic view of a wheel traverse type grinder. 2 is a sectional view taken along line AA of FIG. As shown in this figure, a carriage 3 placed on a grinding table 2 in parallel with the roll 1 is configured to be capable of reciprocating in a roll grinding range, and the carriage 3 has a grindstone as shown in FIG. 4 and the flaw detection device 5 are arranged, and the roll 1 is rotated by the roll rotating device 6 to grind with a grindstone in the circumferential direction of the roll 1. In this case, since the grinding device and the flaw detection device for flaw detection on the roll surface are integrally attached,
When the flaw detection is to be performed on the entire surface of the roll, the flaw detection width is naturally limited.

FIG. 3 is a detailed view of the roll flaw detector. As shown in FIG. 3, when the flaw of the surface of the roll 1 is detected by, for example, an ultrasonic flaw detector, an ultrasonic wave transmission pulse from the pulse generator 7 is transmitted to the roll surface by the oscillator 8 and the roll flaw 9 exists. In the case of doing so, the wave 10 is propagated to the receiver 11 and is caught by the signal processing device 12 as a flaw signal, and is determined as a roll flaw. Reference numeral 13 is a flaw detection device support, and 14
Is a wheel for maintaining a gap.

In such an integrated structure of the flaw detecting device and the grinding device, roll flaw detection may be simultaneously performed in the final pass of finish grinding in order to improve work efficiency. At this time, if you want to perform flaw detection on the entire surface of the roll,
The maximum value of the axial relative speed between the grinding wheel and the roll is determined by the limit of the flaw detection width. That is, FIG. 4 is an explanatory view showing the flaw detection width per pass in the roll axial direction and the roll circumferential direction. As shown in FIG. 4, the flaw detection width for flaw detection in only the final one pass is naturally restricted because the maximum value of the axial relative velocity between the grinding wheel and the roll is set. Therefore, as for the range between the flaw detection width and the roll flaw, a range in which no roll flaw is detected occurs every cycle as shown in FIG.

FIG. 5 is an explanatory view showing a flaw detection condition in the roll axial direction and the roll circumferential direction according to the present invention. Therefore, FIG.
Indicates the case where flaw detection is performed in the final three passes. According to this case, since the flaw is detected one round in the roll axis direction in the final one pass and then the flaw detection width is detected at a certain interval, the next two passes are controlled by shifting the phase, Phase detection for the entire surface of the roll is performed by detecting the phase next to the flaw detected on the circumference and shifting the phase of the non-detected portion again to perform flaw detection on the third pass in the roll circumferential direction. .

In this way, from the relationship with the maximum feed speed determined by the flaw detection width (Δx) for the final plurality of passes of the entire N passes of finish grinding, the feed speed at this time is N × (Δx The flaw detection at that time can be performed by shifting the phase in the roll circumferential direction for each pass by an amount corresponding to the flaw detection width Δx, and flaw detection on the entire roll surface can be achieved after N passes. In this way, flaw detection on the entire surface of the roll can be achieved simultaneously with finish grinding.

[0011]

As described above, by utilizing the final pass of the finish grinding of the roll according to the present invention, the roll flaw detection is controlled by shifting the phase in the roll circumferential direction for each pass by an amount corresponding to the flaw detection width. By doing so, it has an excellent effect that the flaw detection of the entire surface of the roll can be performed efficiently and accurately.

[Brief description of drawings]

FIG. 1 is a schematic view of a wheel traverse type grinder,

2 is a sectional view taken along line AA of FIG.

FIG. 3 is a detailed view of a roll flaw detector,

FIG. 4 is an explanatory view showing the flaw detection width per pass in the roll axial direction and the roll circumferential direction,

FIG. 5 is an explanatory diagram showing a flaw detection situation in a roll axial direction and a roll circumferential direction according to the present invention.

[Explanation of symbols]

 1 roll 2 grinding table 3 reciprocating table 4 grindstone 5 flaw detector 6 roll rotating device 7 pulse generator 8 oscillator 9 roll flaw 10 wave 11 receiver 12 signal processor 13 flaw detector support 14 gap holding wheel

Claims (1)

[Claims] 1. In a roll flaw detection method in the final pass of finish grinding of rolls, roll flaw detection is performed by phase control in which the phase in the roll circumferential direction is shifted for each pass by a plurality of passes of finish grinding to shift a portion corresponding to the flaw detection width. A roll flaw detection method characterized by being performed.