JPS5914723Y2 - Pipe outer surface pre-soaking device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pipe pre-soaking device for wetting the pipe surface with water before measuring the thickness of the pipe with an ultrasonic probe.

In general, seamless pipes are manufactured by punching and forming billets with a rectangular or round cross section on a mandrel using various rolling machines.Due to the manufacturing technology, deviations in pipe thickness in the same cross section, that is, wall thickness unevenness, are inevitably large. up,
Even for a single pipe, there is a problem in that the thickness unevenness of each cross section varies.

This problem not only becomes an important operational factor in heat treatment lines, etc. in the post-process, but also depends on the delivery destination, where the allowable thickness deviation rate is strictly regulated. Measuring the rate quickly and accurately is both extremely important and highly desired by manufacturers of this type of pipe.

By the way, in the past, the quality control of this type of pipe has mainly been done by manually guaranteeing the end of the pipe, and a few rotary pipe thickness measuring devices using the ultrasonic water film method have been proposed. Since it is a rotating type, it is difficult to maintain a water film, and the sliding friction between the pipe and the measuring head causes severe wear, making it impractical. Furthermore, it is not applicable to pipes of various diameters, etc. Due to reasons,
At present, it has not been put into practical use very much.

In view of these conventional problems, the applicant has adopted an ultrasonic measurement method using a water jet nozzle method, and has determined the thickness of the pipe by rotating and feeding the pipe to be measured. While measuring in a non-contact manner in a spiral manner, by reading the pipe thickness information at high speed with a measuring head placed radially from the center of the pipe, we can obtain the thickness unevenness of the pipe cross section and adjust the measurement interval to the pipe axis. length 10m
We have proposed a pipe wall thickness measurement system that can quickly and accurately obtain pipe thickness data over virtually the entire length and circumference of the pipe by using short intervals of about 100 m (September 29, 1978). Patent application filed on date; title of invention: “Pipe Thickness Unevenness Measuring System”).

The present invention was developed as part of the development of a system for measuring uneven thickness of pipes. It is an object of the present invention to provide a pipe pre-soaking device that can obtain accurate ultrasonic pulse echo information by smoothly adapting a water column to the pipe surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a pipe thickness measuring device incorporating a pipe pre-soaking device according to the present invention will be described in detail with reference to the accompanying drawings.

In Fig. 1 showing the entire pipe thickness measuring device, 1 is a regular octagonal measurement frame, 2 is a gate-shaped support frame that supports the measurement frame 1, and the measurement frame 1 has an ultrasonic probe in the water column nozzle. A total of 8 measuring heads 4 with 45
A total of eight measurement heads 4 are supported centripetally at intervals of 0.degree., and supported by a single measurement head drive mechanism 6 relative to the pipe P passing through the regular octagonal inner diameter opening 1a.
The support frame 2 suspends and supports the measurement frame 1 so that it can be raised and lowered by a lifting mechanism 8 installed in the center of the upper frame 2a, and is supported inside the support frames 2b and 2C on both sides. The measurement frame 1 is guided up and down by the guide shaft.

The lower part of the support frame 2 is configured as a truck frame 10, and the truck frame 10 supports a total of four running wheels 14 that run on rails 12 laid in a direction perpendicular to the conveying direction of the pipe P. As shown in FIG. 2, a motor 16 installed at the end of the truck frame 10 and a reducer 18 connected to the motor 16 create a suspension between the sprocket fixed to the output shaft of the reducer 18 and the sprocket fixed to the axle. By driving the chain 20, Y-Y'
It is designed to be able to move in any direction.

Next, the configuration of each part will be explained in more detail.

(a) Measuring head drive mechanism As shown in detail in FIG. 3, a gear motor 22 with a brake is installed on the top of the measuring frame 1, and
The output shaft of the gear motor 22 is inserted into the drive unit casing 26 via a coupling 24, and both ends are connected to bearings 27.2.
8 to a horizontally bearing first drive shaft 30 .

A bevel gear 32 is fixed to the first drive shaft 30 so as not to rotate freely, and the bevel gear 32 has an intermediate portion supported by a bearing 36 at the upper part of a gear box 34 fixed to the mounting board 3 supported on the measurement frame 1. The upper bevel gear 39 of the vertically bearing transmission shaft 38 is engaged.

The gear box 34 has a pair of bearings 41 at both ends,
A second drive shaft 44 is provided horizontally bearing by 42;
A bevel gear 46 fixed to the second drive shaft 44 so as not to rotate freely
is engaged with the lower bevel gear 40 of the transmission shaft 38, while another bevel gear 48, which is pivotally supported within the gear box 34 on the lower side thereof, is engaged with the bevel gear 46 of the second drive shaft 44. I'm letting you do it.

The upper part of the shaft 50 that supports the bevel gear 48 is supported by a bearing 51 provided at the bottom of the gear box 34, and the lower end extending vertically downward is connected to a bearing plate 52 fixed to the lower end of the mounting board 3. A screw shaft for raising and lowering the measuring head is supported by a bearing 53, and the measuring head 4 screwed onto the screw shaft 50 is connected to a pair of screw shafts parallel to the screw shaft 50 supported between the gear box 34 and the bearing plate 52. guide shaft 54.5
Move in the radial direction using the guide number 5.

The second drive shafts 44' of the gear boxes 34' on both sides adjacent to the top gear box 34 are connected to the top gear box 34.
(universal joins on both ends of the second drive shaft 44)
56 and 57 are attached, and by sequentially connecting the second drive shafts of adjacent gearboxes with the connecting shaft, all eight measuring heads 4 in total can be synchronized and the radius can be adjusted. I am trying to displace it in the direction.

In FIG. 3, reference numerals 59 and 60 denote a potentiometer and an encoder which are interlocked with the first drive shaft 30 through a suitable gear system 61 in the drive unit casing 26, and the potentiometer 59 is By outputting the rotation speed of the first drive shaft 30 as a voltage value and outputting the encoder 60 as a pulse, the position of the measuring head 4 can be accurately detected, and the diameter of the pipe whose position is to be measured is measured. It can be automatically adjusted according to the situation.

(b) Measuring head mechanism As shown in FIG. 4, the measuring head mechanism is screwed into the screw shaft 50 of the measuring head lifting mechanism, and
A slide pedestal 62 that is displaced along the guide shaft 54° 55 by rotation of 0, a mounting plate 64 whose upper part is fixed to the slide pedestal 62, and a mounting bracket 65 protruding from the middle part of the mounting plate 64 with a presser bolt. 66, an ultrasonic probe 68 supported vertically downward in the figure, a water column nozzle 70 fixed to the lower part of the mounting plate 64 so as to be coaxial with the ultrasonic probe 68, and a nozzle lower 0a position of the water column nozzle 70. The air nozzle 72 is supported horizontally so as to be orthogonal to the axial direction of the water column nozzle 70, and has an ejection lower 2a opened so that the water column flowing out from the nozzle lower 0a can be thrown horizontally sideways, and the water column nozzle 70. Water supply lower 0b and water supply hose (not shown).

), and a rotary joint 74 connecting the air nozzle 72 and the compressed air hose (not shown).

), and a solenoid valve 78 supported on the top of the mounting plate 54 to control supply and stop of compressed air.
It consists of

Note that the nozzle lower 0 a of the water column nozzle 70 is
It should be brought close to the outside surface of the pipe at a distance of 20 to 30 mm.

It is desirable that water be supplied to the water column nozzle 70 at all times or for some time in advance to avoid entrainment of air bubbles.

However, if water is supplied before the pipe enters, there is a problem that water may enter the pipe.

Therefore, when the pipe passes a pipe detection device (not shown) installed in front of the fixed pipe on the thick side, the air blow solenoid valve 78 is opened to blow air from the air nozzle 72, and from the water column nozzle 70. Blows the jetted water outward.

This air blowing is stopped by closing the electromagnetic valve 78 when the tip of the pipe P has completely passed through the measurement head 4 and reached a position where water does not enter the inner diameter of the pipe P.

As described above, when the air blow mechanism is provided to the water column nozzle 70, water can be supplied to the water column nozzle 70 before the tip of the pipe P reaches the measurement head 4. While the water flow condition within the chamber can be stabilized prior to the start of measurement, air blow
This can prevent water from the water column nozzle 70 from entering the inner diameter portion of the pipe P, and can prevent rust from occurring.

In addition, since the water column in the water column nozzle 70 immediately stabilizes when the air blow is stopped, the dead zone for measuring the bone filling of the pipe P can be made as small as possible, and accurate pipe thickness measurement can be started at an early stage. I can do it.

Note that if the air blow solenoid valve 78 is supported on the mounting plate 54 and the distance from the air nozzle 72 is set small, the air blow can be started and stopped with good responsiveness, and the bone filling insensitive zone can be reduced accordingly. This makes it possible to start measurement earlier.

(C) Measuring frame elevating mechanism As shown in FIG. 5, the measuring frame elevating mechanism 8 includes a bracket 80 that is aligned with the vertical center line of the measuring frame 1 and is installed in the center of the upper frame 2a of the support frame 2. The screw jack 82 is suspended and supported from the lower end of the jack rod 84, and the screw jack 82 is driven by a gear motor 86 with a brake via an appropriate gear system 88 to measure the center O of the measurement frame 1. It has a basic structure in which the measurement frame 1 is raised and lowered so as to coincide with the central axis of the pipe P.

On the other hand, reference numeral 90 denotes a guide shaft whose upper and lower ends are vertically supported inside the side frames 2b and 2C of the support frame 2 by bearing fittings 91 and 92. The measurement frame 1 is fitted with a guide tube 94, and the measurement frame 1 is maintained vertically and smoothly guided and hung by the left and right guide shafts 90.

In addition, in the figure, 95, 96, and 97 are jack rods 84, respectively.
, are dustproof diaphragms provided at the upper and lower parts of the guide shaft 90, respectively.

Further, 98 is the screw shaft 8 of the screw jack 82.
3 through an appropriate gear system 85,
On the side of the encoder 98 there is likewise a suitable gear system (not shown).

) is interlocked with the screw shaft 83 via a potentiometer (not shown).

), and the measurement frame lifting mechanism 8 is automatically controlled by the outputs of the encoder 98 and the potentiometer so that the measurement frame 1 can be aligned with the center of the pipe P to be measured.

Ha) Pre-soaking device This pre-soaking device is for pre-wetting the pipe surface in order to improve the affinity between the water flowing out from the water column nozzle 70 and the pipe surface. , the pre-soaking device 100 opens the inner diameter opening 1 of the measurement frame 1.
It is supported by the measurement frame 1 immediately in front of a.

More specifically, as shown in FIG.
A flange-shaped mounting bracket 1 is installed around the same-diameter opening 1a.
In addition to fixing the inner periphery of the base of the mounting bracket 102, the flange surface 102a of the mounting bracket 102 has annular first and second rings on the inner periphery.
While fixing the brush mounting plate 106 supporting the pre-soaked brushes 104 and 105 on both sides, the pre-soaked brushes 104 and 10
5, an annular first water spray nozzle 108 is supported at an appropriate interval with respect to the first pre-soaking brush 104, and an annular first water spray nozzle 108 is supported at an appropriate interval behind the second pre-soaking brush 105. It has a basic structure that supports the second water spray nozzle 110.

In this case, the nozzle opening of the first water spray nozzle 108 supported before and after the first pre-watering nozzle 104 is directed in such a direction as to spray water onto the first and second pre-watering brushes 104 and 105, as shown by arrow a. The outer surface of the pipe P being conveyed is first wetted with the first pre-soaking brush 104 containing water spray, and the first and second pre-soaking brushes 104 and 105
The scale and the like attached to the surface of the pipe 12 are removed, and then the surface of the pipe P is cleaned using the second water spray nozzle 110 whose nozzle opening is opened toward the inner diameter of the opening 1a of the measurement frame 1. It is preferable to wet the entire circumference of the pipe P and send the pipe P to the measurement head 4 in the wet state so that it blends well with the water column of the water column nozzle 70.

Note that depending on the surface properties of the pipe P, the number of sprinkler pipes and/or pre-soaking brushes may be increased or decreased, or the arrangement may be changed.

When a pre-soaking device as described above is provided, the surface of the pipe P can be kept in a good wet state, so that the pipe thickness data obtained by the measuring head 4 can be extremely stable and accurate. I can do it.

Figure 8 shows a pipe with a nominal outer diameter of 216.3 mmφ and a nominal pipe thickness of 8°2.
The same pipe P with a diameter of 0 mm is lined at a line speed of 40 m/min.
Fig. 8 shows the pipe thickness data when the pipe is sent by the method, and Fig. 8 shows the case without pre-soaking, and Fig. 8 II shows the case when pre-soaking is performed by the pre-soaking device according to the present invention.

As is clear from the comparison between the two, in the case without pre-soaking, many whisker-like "skips" can be seen, whereas in the case with pre-soaking, no such jumps can be seen. It can be seen that an extremely stable table can be obtained.

Next, the operation of the pipe thickness measuring device having the above configuration will be explained.

In advance, the measurement frame 1 is aligned with the pipe P to be measured by the lifting mechanism 8, while each measurement head 4 supported on the measurement frame 1 is moved according to the nominal diameter of the pipe P by the measurement head drive mechanism. Pipe P to move forward and backward and pass through.
Set at a distance of 20 to 30 mm from the outer peripheral surface of the

The pipe P to be measured is ■Roller conveyor (not shown).

), etc., and when it reaches the front of the pipe thickness measuring device, the detection device of the pipe P detects this, and the first and second scattering nozzles 108.11 of the pre-soaking device
At the same time as starting water supply to the water column nozzle 70 of the measuring head 4 and the measuring head 4, the air blowing solenoid valve 78 is opened to start air blowing by the air nozzle 72.

When the tip of the pipe P finishes passing through the measuring head 4, the air blowing is stopped, and the measuring head 4 starts measuring the pipe thickness using the ultrasonic pulse echo method.

The pulse echoes received by the ultrasound probe 68 of each measurement head 4 are simultaneously transmitted to a measurement circuit (not shown).

), and the pipe thickness value is obtained by a well-known processing method that utilizes the fact that the time interval of pulse echoes is proportional to the pipe thickness, and these pipe thickness data are used for calculations of wall thickness deviation, etc. Then, it is finally determined whether the measured pipe P is good or bad.

As is clear from the above description, the present invention is arranged at the front end of an ultrasonic measurement head that obtains pipe thickness information by ultrasonic pulse echo, and includes a first annular water spray nozzle, a first and a second thousand submerged brushes, and a third submerged brush. To provide a pre-soaking device for a pipe, which has a structure in which two water spray nozzles are coaxially arranged in close proximity to each other in this order, and wets the outer surface of the pipe to be measured with water in advance before measurement. Therefore, according to the present invention, the outer surface of the pipe sent to the measuring head can be well wetted by the combination of the water sprinkling pipe arranged in multiple stages and the pre-soaking brush, and the measurement by the measuring head can be made extremely stable. , the more accurate data can be obtained.

In the above embodiments, a water column nozzle type measuring device has been described, but it goes without saying that the present invention can also be applied to a water film type measuring device.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the entire pipe thickness measuring device, Fig. 2 is a side view of the same, Fig. 3 is an enlarged sectional view of main parts showing the drive mechanism of the measuring head of the pipe thickness measuring device, and Fig. 4 is the above 5 is a front view showing the elevating mechanism of the measuring frame, FIG. 6 is a side view of the measuring frame, and FIG. 7 is a vertical sectional view showing the pre-soaking mechanism according to the present invention. FIGS. 8 I and II are graphs showing actually measured pipe thickness data obtained without pre-soaking and with pre-soaking, respectively. 102...Mounting bracket, 104.105...First and second pre-soaking brushes, 106...Brush mounting plate, 108.
...First water spray nozzle, 110...Second water spray nozzle, 1
... Measuring frame, 4... Measuring head.

Claims (1)

[Scope of utility model registration request] It is placed in front of a measuring device that measures the thickness of a pipe using a water film type or water column type ultrasonic probe, and includes multiple annular sprinkler pipes and multiple annular brushes installed on the concentric outer circumference of the pipe. A pre-soaking device for the outer peripheral surface of a pipe, in which a sprinkler pipe, a brush, and a sprinkler pipe are arranged close to each other in this order in the direction of pipe travel.