JPS60119411A - Roll diameter detecting device of rolling mill - Google Patents

Abstract

PURPOSE:To prevent a measuring water current from falling into disorder, and to detect a roll diameter with a high accuracy by installing a drain board on the surface of a roll of the upstream side in the rotating direction of a roll to be measured, against a fitting position of an ultrasonic probe. CONSTITUTION:A drain board 10 is fixed onto a case 2 through a bracket 11 on the upstream side of a rotating direction z of a roll 1, against a fitting position of an ultrasonic probe 3 which can move freely in parallel to the axial direction of the roll 1. For instance, the drain board 10 consisting of rubber, plastic and a non-ferrous metal is formed as one body with the probe 3 freely movably in parallel to the axial direction of the roll. A little gap of a degree that the drain board 10 touches lightly the surface of the roll 1, and this device is installed so as to make an inclination angle alpha.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to an ultrasonic type detection device among roll diameter detection devices for a rolling mill.

In general, in plate rolling mills such as hot rolling mills, the work rolls are locally worn out only in the areas where they contact the rolled material, so in order to roll a plate with a normal thickness distribution, the rolling order of the rolled material is It is necessary to shift from wide width to narrow width, and therefore most rolling mills currently adopt such rolling order regulation.

However, such rolling order regulation based on sheet width has become an extremely large factor that hinders productivity, and there is a growing demand for eliminating such a factor.

Therefore, as a measure to eliminate such restrictions on the rolling order, a new online roll grinding method has been proposed in which the surface of the work roll is ground to a desired profile while the work roll is installed in a rolling mill stand. A typical example of this kind of grinding means is to press a grinding body such as a grindstone against the surface of the roll while rotating the work roll, and to move the grinding body parallel to the roll axis to shape the work roll into a desired profile. Grinding devices are known. When performing such online roll grinding, in order to obtain the required roll profile with high precision, it is necessary to accurately detect the outer diameter of the roll to be ground before, after, or during grinding and to understand its surface profile. is essential.

Although non-contact type detectors are often used as roll diameter detection devices for this purpose, a roll diameter detection device having an ultrasonic type detector will be particularly described here.

FIG. 1 is an explanatory diagram of a hot rolling mill in which, for example, a conventional ultrasonic roll detection device is used for an upper work roll 1. As shown in the figure, an ultrasonic probe 3 is housed in a sealed case 2 arranged at an appropriate distance from the roll 1 so as to face the roll 1 at an appropriate distance X. This is mounted on a support beam (not shown) so as to be freely movable in parallel in the roll axis direction (perpendicular to the plane of the paper), and is in contact with a time interval measuring device 5 via a transducer 4.

Further, a nozzle hole 6 is provided in the case 2 on the roll 1 side.
However, measurement water supply lowers are formed on the other surfaces, and the case 2 is connected to a fresh water supply source having pressurizing means such as a pump (not shown) via the measurement water supply lowers.

When measuring the roll diameter with this detection device, measuring water is spouted from the nozzle hole 6 while rotating the roll 1 at an appropriate speed to immerse the gap 9 between the probe 3 and the roll 1 in water. , when excited by the transducer 4, the ultrasonic waves are reflected on the surface of the roll 1, reciprocate in the measuring water flow, and return to the probe 3. When the time difference t between the transmitting pulse output and the receiving pulse output of the converter 4 is detected by the time interval measuring device 5 as shown in FIG. Gap X can be detected. Here, ■ is the speed of sound in water.

Therefore, the diameter of the roll 1 can be determined from the above value of X, and the roll profile can be easily and accurately measured by detecting X without moving the probe 3 parallel to the roll axis direction can do.

On the other hand, normally in a hot rolling mill or the like, during rolling, the surface of the roll 1 is cooled by jetting a coolant 8 such as water, so the roll diameter is detected with the coolant 8 adhering to the surface of the roll 1. There are many cases. In this case, as the rotational speed of the roll 1 increases, the coolant 8 adhering to the coated surface of the roll 1 will be mixed with the measuring water flow and the gap portion 9 as shown in FIG.
The water collides with the water, separates from the surface of the roll 1, and flows into the measurement water stream again. At this time, surrounding air is drawn in and bubbles are generated in the water flow in the gap portion 9.

However, once bubbles are generated, the ultrasonic waves are reflected from the bubbles, resulting in a misdiagnosis that the gap If it is not possible to generate a pulse, a problem arises in that the gap X cannot be detected.

The present invention has been made to effectively solve such problems, and its purpose is to entrain air into the measurement water flow at the cap portion between the probe and the roll and to reduce the measurement water flow. An object of the present invention is to provide a roll diameter detection device for a rolling mill that can prevent disturbances in the roll diameter and detect the roll diameter with high accuracy.

In order to achieve such an object, the present invention provides a roll diameter detection device for a rolling mill that uses ultrasonic waves. The gist of this is that a drainage board was installed.

5- A preferred embodiment of the present invention will be described below with reference to FIG.

FIG. 3 is a schematic explanatory diagram including a cross section of an ultrasonic probe portion of a detection device according to an embodiment of the present invention, and the same members as in FIG. The explanation will be omitted. Attachment of the ultrasonic probe 3, which is housed in the water passage case 2 as shown in the figure and can freely move parallel to the axial direction of the roll 1 (direction perpendicular to the page) on a support beam (not shown). A draining plate 10 is fixed on the case 2 via a bracket 11 on the upstream side in the rotational direction Z of the roll 1 (in the illustrated example, above the probe 3) with respect to the position, and the draining plate 10 is attached to the probe. 3 and is configured to be freely movable in parallel in the roll axis direction. The drain plate 10 is made of a soft material that will not damage the surface of the roll 1 even if it comes into contact with the surface of the roll 1 made of materials such as rubber, plastic, and non-ferrous metals.
The drain plate 10 is placed between this and the surface of the roll 1.
A slight gap is formed that allows the surface to be lightly touched. Historically, the tip of the draining plate 10 on the roll 1 side forms a wedge, and the draining plate 10 is installed so as to form an appropriate inclination angle α (preferably α is an acute angle) with respect to the roll 1 surface. The length and width (in the roll axis direction) are determined so that at least the coolant 8 adhering to the surface of the roll 1 does not obstruct the measurement water flow in the gap 9 between the probe 3 and the roll 1.

Further, the draining plate 10 is fitted into a groove 13 of a bracket 11 via a plurality of bolts 12 so as to be freely inserted into and taken out from the roll 1 side.

If the device of the present invention is used according to the same procedure as the conventional method, the coolant 8 adhering to the surface of the roll 1 will be scraped off by the draining plate 10 on the upstream side (front side) where it flows into the ultrasonic probe 3 during measurement. Therefore, the measurement water flow in the gap 9 between the probe 3 and the roll 1 is not disturbed, and the surrounding air is not dragged into the water flow in the gap 9, unlike in conventional devices. Problems such as misdiagnosis of the gap x1, that is, the diameter of the roll 1 due to the reflection of ultrasonic waves at the bubbles, a decrease in the received wave intensity due to diffuse reflection at the bubbles, and the inability to detect the gap X are resolved. Accurate roll diameter and stable detection of roll profile is possible.

Similarly, the tip of the drain plate 10 is worn out as the measurement progresses, or the roll 1 is worn out as the rolling progresses, and its diameter becomes smaller, so the gap between the drain plate 10 and the roll 1 increases. Although the effect of the drain plate 1O is reduced, this can be countered by loosening the mounting bolt 12 and pulling the drain plate 10 outward from #13.

Although the present invention has been described above with reference to embodiments, the present invention is not limited to the above-mentioned embodiments, and may be modified and improved as appropriate without departing from the spirit of the present invention. .

As is clear from the above description, according to the present invention, a drain plate is provided on the roll surface on the upstream side in the rotational direction of the roll to be measured with respect to the mounting position of the ultrasonic probe, so that there is no space between the probe and the roll. The roll diameter can be detected with extremely high accuracy by preventing the gap portion from being caught in the measurement water flow and from disturbing the measurement water flow.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a roll diameter detection device according to a conventional example;
The figure is a diagram showing the time difference between the output of the transmit pulse and the output of the received pulse from the converter, and FIG. 3 is an explanatory diagram of the roll diameter detection device according to the present invention. In the drawing, 1 is the roll, 2 is the water flow case, 3 is the ultrasonic probe, 4 is the converter, 5 is the time interval measuring device, 8 is the coolant, 9 is the gap, 10 is the drain plate, and X is the drain plate. It's a gap. 9-

Claims (1)

[Claims] In a rolling mill roll diameter detection device that uses ultrasonic waves,
1. A roll diameter detection device for a rolling mill, characterized in that a drain plate is installed on the roll surface on the upstream side in the rotational direction of the roll to be measured with respect to the mounting position of the ultrasonic probe.