JPS6071145A - Finishing device for pipe line weld bead - Google Patents

Abstract

PURPOSE:To carry out finish-machining of a weld bead of a pipe line to a uniform height with respect to the outer surface of the pipe line, by providing, in a finishing device for weld beads on pipe lines, means for measuring the distance between a cutter or grinding stone and the outer surface of the pipe line, means for controlling the amount of cut-in and means for controlling the speed of feed. CONSTITUTION:A guide ring 2 arranged around a pipe line 1, circumferentially moves to serve as a guide rail. A carriage 6 is attached with a drive device 8 and a cutting device 17 so thast the carriage 6 may be moved by the power of a DC motor. The cutting device 17 carries a magnetic sensor 18 power of a DC motor. The cutting device 17 carries a magnetic sensor 18 for measuring the distance between the outer surface of a mother material and a milling cutter 16. A computing circuit in a microcomputer in a control panel controls the amount of cut-in in accordance with the output of the magnetic sensor 18 to carry out the cutting. Cutting or grinding load may be detected from variations in the rotational speed of an air motor 14 or variations in torque of the motor. Further, the control of feed speed may be made by detecting the rotational speed of the air motor 14 with the use of a tachometer generator 15.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an apparatus for smoothing a weld bead of a pipe by cutting or grinding it.

[Background of the invention]

Conventionally, this type of finishing equipment has been used to attach an annular guide ring around the piping, use this as a guide rail, and install a cutting (grinding) device on a carriage that rotates around the circumference of the piping. The purpose is to finish the bead smooth, and the cutting (grinding) force of the cutting (grinding) device is adjusted by a spring.

However, with this conventional finishing device, cutting (
Since the speed (grinding) changes, the surface roughness cannot be uniformly finished, and if the piping is horizontal or diagonal, for example, cutting (grinding) on the spring may be difficult.
Since the weight of the grinding) device is directly applied, the spring expands and contracts accordingly, and as a result, the cutting (grinding) pressure fluctuates, causing the pressure to become too high or too low. A situation occurs.

In addition, this type of finishing equipment is often used in narrow spaces with unstable footing, so it is necessary to make the equipment more compact and lightweight to make it easier to handle. When miniaturized, the problem arises that the output is small and work efficiency cannot be improved. In particular, if the center of the guide ring and the piping are misaligned, or if the piping itself is distorted, the welding bead may not be able to be scraped due to the circumferential position of the piping, or the surface of the piping itself may be scraped. If the temperature exceeds the specifications, the motor may stop rotating and work may become impossible. At this time, if the device is forced to move in the circumferential direction of the pipe, there is a risk that the device itself will be damaged. Furthermore, the influence of wear of the grindstone during grinding could not be avoided in the past.

Due to the above-mentioned causes, it has not been possible to properly finish pipe weld beads using conventional equipment.

[Purpose of the invention]

It is an object of the present invention to maintain a constant position on the piping surface without causing an overload during cutting or grinding, regardless of the orientation of the piping and even if the relative positional relationship between the piping surface and the guide ring is not accurate. An object of the present invention is to provide a piping weld bead finishing device capable of cutting or grinding a weld bead to a height of .

[Summary of the invention]

The present invention is characterized in that the pipe weld bead finishing apparatus of the type described above includes a measuring means on a carriage for measuring the distance between a cutting cutter or a grinding wheel and the pipe surface with respect to the weld bead, and a cutter based on the output of the measuring means. or a cut amount control means for cutting the grindstone to a predetermined height from the piping surface, a load detection means for detecting the cutting or grinding load, and a cutter or cutter for keeping the load within a predetermined range based on the output of the load detection means The present invention further includes a feeding speed control means for controlling the circumferential feeding speed of the guide ring of the grindstone.

[Embodiments of the invention]

Embodiment (1) First, an embodiment of the apparatus of the present invention will be described when it is implemented as a finishing apparatus for finishing a weld bead by cutting.

FIG. 1 is a view seen from the longitudinal direction of the pipe, and a two-part guide ring 2 connected by a peel bolt 3 is arranged around the pipe 1, and this guide ring 2 is connected to a tightening piece 4. and tightening? It is roughly aligned with the piping 1 by the bolt 5 and is flanged to the piping 1 so as not to move in the axial and circumferential directions. Above the guide ring 2 is the bolt 6.
A two-piece carriage 6 connected at 1 is mounted so as to be movable in the circumferential direction of the pipe 1 via rollers 7 using a guide ring 2 as a guide rail.

A drive device 8 and a cutting device 17 are mounted on the carriage 6 . The drive device 8 is for rotating the carriage 6 along the guide ring 2, and the power of the DC motor 9 incorporated therein is transmitted to the ring gear of the guide ring 2 via the gear 10. This is to rotate the Siccalizo 6. A potentiometer 11 rotated by a gear 10 is used to detect the rotational position of the carriage 60.

The magnetic sensor 1B is supported by the cutting device 17 and
This is for measuring the distance between the base material surface of the pipe 1 and the milling cutter 16. In other words, pipe 1 was distorted)
Alternatively, if the center of the guide ring 2 does not coincide with the center of the pipe 1, the radial distance between the base material surface of the pipe 1 and the milling cutter 16 will change depending on the rotational position during cutting. is detected by the magnetic sensor 18, and the depth of cut of the milling cutter is automatically corrected and changed in-process, so that the weld bead is always cut to a constant height from the surface of the base material of the pipe 1.

FIG. 2 shows an installation diagram of the magnetic sensor 18 and the milling cutter 16. The magnetic sensor 18 is attached to the cutting device 17 (D cutting arm 20) by a mounting plate 19 so as to face the surface of the pipe base material near the weld bead B of the pipe 1 without contacting it. , the distance ΔH' between the tip of the sensor 18 and the surface of the pipe is measured by extracting changes in the strength of the magnetic field generated around the metal pipe 1 as a voltage, and its characteristics depend on the material of the pipe 1. In the case of stainless steel and carbon steel, the surface changes as shown in Figure 3.The surface of the magnetic sensor 18 is at a distance ΔH from the surface of the milling cutter 16.
It is located 2 times higher. In addition, the distance ΔH1 from the surface of the piping base material to the fly cutter 16 is ΔH0=
It is expressed by the formula ΔH - ΔH3. This is calculated by a microcomputer inside the control device.

FIG. 4 shows the general state when the guide ring 2 is installed on the pipe. As shown in the figure, even when the guide ring 2 is aligned with the piping 1 and installed, the guide ring 2
The center oP of the pipe 1 and the center O6 of the guide ring 2 do not necessarily match due to mechanical tolerances, distortion of the pipe 1, and errors in subsequent installation. For this reason, the surface of the pipe 1 is cut at the position of the radius RP in FIG. 4. On the other hand, radius R6
At the position, there may be a case where there is a distance ΔH2' between the weld bead B and the tip of the milling cutter 16, and the weld bead rB cannot be cut. In order to prevent the above-mentioned situation where the cut is too large and the pipe cannot be cut at all, it is necessary to keep the slice cutter at a constant distance from the surface of the pipe when cutting.

Therefore, in this embodiment, the cutting depth of the cutter 16 in the radial direction of the pipe 1 is controlled as follows.

The distance ΔH from the pipe surface to the tip of the sensor is measured by the magnetic sensor 18, and based on this measurement, the distance ΔH1 (ΔH□
=ΔH−ΔHz) is calculated by the arithmetic circuit of the microcomputer in the control panel. Based on this data, the cutting device 17
The milling cutter 1 is driven to a predetermined first cutting distance ΔHs as shown in FIG.
6 is lowered and the first cutting is performed on the weld bead B. During this cutting, the measured value of the magnetic sensor 18 is fed back to the microcomputer to calculate the distance ΔH1 in-process and compare it with the predetermined cutting distance ΔH8.
If ΔH1 deviates from ΔH8, ΔH1 becomes ΔHll
The milling cutter 16 is moved in the radial direction of the pipe 1 until it becomes equal to , and cutting depth control is performed such that the distance from the pipe surface to the cutting surface is always maintained at a predetermined constant value ΔH5.

Next, in the second cutting, the milling force 16 is further lowered from the distance ΔHs by a preset cutting depth t, and cutting is performed while performing cutting depth control similar to that described above.

Thereafter, in the same way, as shown in FIG. 5(b), the nth cutting is performed while maintaining the cutting distance ΔHn'lrΔHn−ΔHBnt.

In order to prevent over-shaving into the pipe base material, as shown in Fig. 5(c), the preset remaining amount Hc is adjusted by the previous ΔH.
When the microcomputer detects that He′>”ΔHn, cutting is completed.

The above is the cutting control in this embodiment.

Now, whether the weld bead P of the welded part is welded by hand or by automatic welding, there will be some unevenness in the weld bead. This causes load fluctuations during cutting. Furthermore, since the above-mentioned depth of cut control is performed during cutting, the amount of depth of cut actually changes every moment during cutting, and as a result, the load is constantly fluctuating.

If the magnitude of this fluctuating load is less than the rated load of the motor, there will be no problem, but if it exceeds this, there will be an overload condition, and the rotation of the motor for driving the milling cutter 18 will stop, causing cutting. becomes impossible.

In this case, there is a risk of damage to the equipment, and the work will be interrupted, leading to a decrease in work efficiency.

In order to solve the above problem, the apparatus of this embodiment performs feed speed control as described below.

In order to make the device of this embodiment compact and lightweight,
An air motor 14 that can provide a relatively high output per volume is used as a drive source for the milling cutter 16. FIG. 6 shows an air motor 140 rotation speed-torque characteristic diagram and a torque-horsepower characteristic diagram.

As shown in this figure, the air motor has a rotation speed N and a torque T.
Since this relationship shows a drooping characteristic, the load fluctuation, that is, the torque fluctuation, of the milling cutter 16 corresponds to the rotation speed fluctuation. That is, in order to detect changes in the load, it is sufficient to detect changes in the rotational speed of the air motor.

The relationship between the torque T6 required for cutting, the torque T of the air motor, the rotation speed N, and the horsepower H (PS) is expressed by the following equation.

(1) Required cutting torque T.

To=KX t
T+N0: Proportional constant No.: No-load rotation speed (3) Grinding horsepower H (PS) I ((PS) = NXTc/716.2 On the other hand, when cutting starts, the unevenness of the bead and the above-mentioned cutting depth control The depth of cut constantly changes, causing load fluctuations and the required cutting torque to change. Therefore, the rotation speed changes due to the characteristics of the motor. Now, the characteristics shown in Figure 6 In the diagram, cutting is performed with torque T1 and rotation eN1 such that the horsepower reaches the maximum H0, and the above cutting ρ
Due to the change in the depth of cut, if the depth of cut changes from t□ → t2 (tx > tx) with cutting progressing to a certain extent, the torque and rotational speed will become T1 → TB r N1 →
Changes to NH. If the load torque T11 becomes more than the stall torque of the air motor 18, the rotation speed N=09.
The rotation of the air motor will stop, causing undesirable situations such as damage to the machine and reduction in cutting efficiency. Therefore, in this embodiment, a tacho generator 15 is installed at the rear of the air motor 14.
The number of revolutions N of the shear motor 14 is sampled and detected by a microcomputer, and if N1-
If N) is 0, it is determined that the load is large and the circumferential simultaneous feed amount ■ is decreased, and if N1-N (0), it is determined that the load is small and the circumferential simultaneous feed amount V is increased.The above control is performed. Particularly, cutting is performed in the range from the horsepower H2 to the maximum horsepower H□ shown in FIG.

The above is the transmission speed control in this embodiment.

However, in this embodiment, the above-mentioned feeding speed control should be carried out with care, since the milling cutter 16 is used, the cutter cutting edge cuts at a certain interval, which is an intermittent cutting process. It means that it becomes action. As shown in FIG. 7, due to the influence of this intermittent cutting, the rotation speed of the shimoter 14 repeatedly increases and decreases rapidly at time intervals ΔT8. Now, if cutting is being performed under the normal load condition shown in Figure 7 (,), and the depth of cut becomes large, and then the overload condition occurs as shown in Figures (b) and (c), the actual load fluctuation will be (
(variation in rotational speed) is ΔN8. Although it is expressed as ΔN2, due to the vertical movement of the rotation speed, the rotation speed detection by the tacho generator 15 happens to detect the 0 point, and then (
If two points are accidentally detected when the overload condition b) occurs, a problem arises in that the actual load fluctuation of ΔN□ is not detected and overload cannot be detected. The same applies to point Q and point R.

To solve this problem, the fluctuation in the output of the tachogenerator 15 based on the vertical movement of the rotation speed of the motor 14 is
As shown in (aγ, (b)', (e)' in the figure), it is sufficient to use a means of averaging processing and sampling using a capacitor.

FIG. 8 shows a block diagram of the cutting depth and feed speed control system.

Part A of FIG. 8 is a block diagram of feed speed control, and part B is a block diagram of cutting depth control.

Part 0 represents a block diagram of computer control inside the control device 63, which will be described later.

The priority order of this control is cutting depth control and feed rate control.

First, cutting control will be explained below.

The purpose of this control is to keep the height of the weld bead constant across the piping surface.

The following three states can be considered for the cutting depth control.

(1) When the distance H2 between the milling cutter 16 and the piping surface is equal to the initial setting height H, that is, when H,=H, (z) When nl>ax (3) When Hl<H2 I will explain below.

In the case of H,=H, the height deviation JH in the block diagram becomes 0. At this time, on the table of the height deviation ΔH and the applied voltage V to the amplifier of the motor 12, which is prepared in advance inside the calculator, the applied voltage V=O.
Therefore, the motor 12 does not move.

When H > Ht, the height deviation ΔH is a negative value. On the sinusol, a negative set voltage is applied to the motor regardless of the magnitude of ΔH, and the milling cutter 16 has a negative value of H1=
Feedback control is performed via the magnetic sensor 18 until I(, .

As a result, the vertical movement of the chisel cutter 16, which is in the state (1), is stopped.

When Ht<Hz, the deviation ΔH is a positive value. Regardless of the magnitude of ΔH on the table, a positive voltage is applied to the motor 12, and the Schiff cutter 16 is applied until H1=H (2 ) is controlled in the same way.

As a result, the chiseling cutter 16 is again in the state (1).
stops.

In actual cutting control, one of the three states mentioned above is always selected.

Next, feed speed control will be explained below.

The purpose of this control is to prevent overload of the air motor, which is the drive source of the milling cutter 16, by lowering the feed speed, and to increase work efficiency by increasing the feed speed when the load is small. It's about raising.

In the case of this control, the following three states are possible depending on the load. In this case, the load is considered as the rotational speed of the air motor as described above.

(1) When the air motor 14 is overloaded, that is, when the actual rotation speed N is lower than the set lower limit rotation speed NL, that is, when %N<NL (2) When NL≦N≦NH (3) N >NH case will be explained in order below.

If N<NL, a positive voltage is generated in proportion to the deviation based on a table of the rotational speed of the air motor 14 and the deviation voltage prepared in advance inside the computer. Next, a voltage obtained by subtracting this deviation voltage from the set voltage is applied to the DC motor 9 of the circumferential simultaneous transmission 9 via an amplifier. Therefore, the DC motor 9
The speed at which the milling cutter 16 is fed through the milling gear 10, which has a low rotational speed, is reduced.

As a result, as mentioned above, the load is reduced and the air motor 14
The number of revolutions gradually increases. This change in rotational speed is converted into voltage by the tacho generator 15, and the rotational speed N is determined by referring to a voltage-revolution table for the tachogenerator 15 prepared inside the computer.

Thereafter, the above-described operation is repeated repeatedly until the rotational speed N satisfies NL≦N≦NH.

If NL≦N≦NII, the deviation voltage is 0, so the device operates at the sending speed determined by the initial setting voltage.

When N>NH, the operation is opposite to the case (1).

FIG. 9 shows an overall control system diagram of the apparatus of this embodiment. Codes that are the same as those previously used indicate the same parts. The control device includes a microcomputer 23, a control circuit 24, and an operation panel 25. Motor 9 used in this example device
Actuators such as e12+14 and detectors such as potentiometers 11 and 13 are all connected to a microcomputer 23 via an interface such as a leg converter 22, and are controlled by a program stored in this memory area.

Next, a work flowchart of the apparatus of this embodiment will be explained with reference to FIG.

First, information necessary for cutting, such as the pipe diameter, cutting feed speed, -cut depth, final bead height, etc., is input into the microcomputer 61 through interaction with the control device.

Next, the automatic origin return button causes the movable device 8 and the milling cutter 16 to return to their origin.

Furthermore, when the automatic start methane is started again, the air motor 1, which is the drive source of the milling cutter 16, starts.
4 rotates, and then the milling cutter is positioned at the first cutting position calculated based on the input information while cutting the weld bead in the vertical direction via the magnetic sensor 18.

After this, the drive device 8 travels in the circumferential direction, and the distance of the milling cutter from the piping surface is measured in-process via the magnetic sensor 18, and the cutting depth is controlled within the microcomputer based on this data. Tsutsu,
At the same time, the cutting load is sampled and detected at certain intervals. If the load is outside the predetermined range (N < N,
(or N>Nu), feed speed control is performed and cutting is always performed with an appropriate cutting load.

The position of the drive device 8 is constantly monitored by a potentiometer. When one round of cutting is completed, the drive device 8 is first stopped, the milling cutter is positioned at the next cutting position, and the above-mentioned operation is repeated thereafter.

In this way, cutting is performed automatically until a predetermined cutting position is finally reached, and when the final cutting is performed, the drive device 8 stops, and the milling cutter 16 rises to the home position, stopping the entire operation. do.

Embodiment (2) Next, as another embodiment of the present invention, an example of a finishing device for finishing a pipe weld bead by grinding will be described.

FIG. 11 is a diagram of the apparatus of this embodiment viewed from the longitudinal direction of the piping, and the same parts as in FIG. 1 are designated by the same reference numerals. However, in this embodiment, 17 is not a cutting device but a grinding device, and 16' is its grindstone. 37 is a shape detection device provided on the carriage 6, which measures the height of the weld bead across the surface of the pipe 1 in the circumferential direction, and
Measure the distance between the surface of the pipe 10 and the guide ring 2,
This is for checking the installation condition of the guide ring 2.

FIG. 12 is a diagram showing the structure of the shape detection device 37,
Potentiometers 41 , 42 are mounted on a support plate 40 that can be slid by a DC motor 39 along a support 38 fixed to the carriage 6 , each of which has rolling rollers 43 that touch the surface of the pipe 1 and the weld. It is brought into contact with bead B.

The difference between the outputs of potentiometers 41 and 42 represents the bead height HB at that position;
The variation in the output represents the variation in the distance between the guide ring 2 and the pipe 1.

13 and 14 are cross-sectional views showing the grindstone drive mechanism and grindstone cutting mechanism of the grinding device 17.

In these figures, the driving force of the air motor 14 is transmitted via screw gears 44 and 45 to a spindle 46 to which a grindstone 16' is fixed. The grindstone 16' is fastened to the spindle 46 with a nut 48 through the frictional force of a spacer 47. A grinding head 50 carrying a bearing 49 of the spindle 46 is slidably supported on the main body 17 and is rotated by the rotation of the DC motor 12 being transmitted to the screw shaft 53 via screw gears 51, 52. Natsuto 54
Through this, the grinding head 50 performs a cutting movement.

The depth of cut of the grindstone 16' at this time is detected by the potentiometer 13.

Furthermore, since the grinding wheel 16' is prone to wear during grinding, this embodiment is provided with a grindstone wear amount detection mechanism to cope with this problem. This mechanism measures in-process the diameter of a grindstone 16' that is consumed during grinding work, and has a light projector 56 and a light receiver 57 mounted inside a grindstone cover 55 as shown in FIG. Figure 15 (
&) shows the state of the grindstone before grinding, and (b) shows the state of the worn grindstone after grinding for a certain period of time. A parallel beam of light emitted from the light projector 56 is received by a light receiver 57 mounted opposite to the grindstone 16'. When the grinding wheel 16' wears down by ΔH due to grinding work, the light receiver 57 wears down by this amount.
The amount of light entering increases from ■□ to v2.

The light receiver 57 is an element that converts the incident parallel light beam into voltage and current, and the output voltage and current values change according to the difference in light amount. Therefore, the amount of wear ΔH can be measured by calculating this amount of change using a microcomputer.

Now, in this embodiment using a grindstone, as in the case of the previous embodiment using a milling cutter, there are various factors such as the alignment between the guide ring 2 and the pipe 1, the mechanical tolerance of the guide ring 2, the distortion of the pipe itself, etc. In addition, since the distance between the guide ring 2 and the pipe 1 is not necessarily uniform at all positions in the circumferential direction, the bead cannot be ground at a certain position in the circumferential direction, and the surface of the pipe is ground at a certain position. A situation occurs. In order to prevent this, it is necessary to keep the grindstone 16' at a constant distance from the surface of the pipe during grinding.

In this embodiment, the cutting of the grindstone 16' in the radial direction of the pipe 1 is controlled as follows.

First, let the angle from the circumferential reference position be ψ, and as a function of ψ, the bead height HB (ψ), the piping The distance H (ψ) from the surface to the rail surface of the guide ring 2 is measured at every constant angular increment lψ in the circumferential direction.

Next, from this data, the distance R from the center of the guide ring to the piping surface at the angle ψ, (ψ)=RR−H(ψ) is calculated. (RIL is the radius of the guide ring 2.) Next, the grinding position of the grindstone 16' (distance from the center of the guide ring)
RG is calculated using formula R6 from the above RP (ψ) and the preset bead remaining height He (however, Hc is constant in the circumferential direction).
(ψ) = R, + Hc is calculated by the arithmetic circuit of the microcomputer.

If the DC motor 12 is driven by the information on the grinding position R6 (ψ) of the grinding wheel 16' at the angle ψ calculated by this microconbeater, and the position is feedback controlled (by the potentiometer 13), the piping 1 Can be ground to a constant height from the surface.

However, when grinding is performed many times, the grinding wheel 16' itself wears out and its radius changes. Therefore, with only the above-mentioned grinding depth of cut control, the depth of cut is insufficient by the reduced radius of the grindstone 18.

In order to solve this problem, the non-contact type grindstone wear detection mechanism described in FIG. 15 detects the voltage change ΔV=V, -V1 corresponding to the external dimensions of the grindstone in-process. This voltage change ΔV is converted into a wear amount ΔH by a microconbeater, and based on this data, the DC motor 12 is driven with feedback from the potentiometer 13 to correct the depth of cut.

The above is the cutting control in this embodiment.

Now, in this embodiment as well, fluctuations in the grinding load occur due to the same reasons as described in the previous embodiment using a milling cutter, and the grinding wheel drive motor stops, causing damage to the equipment and interrupting the work. Get up. In order to prevent this, the feeding speed is controlled as follows in this embodiment as well.

In this example as well, in order to achieve compactness and weight reduction,
An air motor 14 capable of producing a relatively high volumetric output is used as a drive source for the grinding wheel 16'.

Its characteristics are the same as in FIG.

As described above, load fluctuations can be detected by detecting rotational speed fluctuations.

The relationship between the torque T0 required for grinding, the torque T of the air motor, the rotation speed N, and the horsepower I ((PS) at this time is the following formula % formula % (1) Required grinding torque T0 Tg = KXtXbXrq K: proportionality constant t: depth of cut Quantity b = Grinding width rG: radius of grinding wheel (2) Relationship between air motor torque T and rotation speed N = -R
T+N0 R: Proportional constant No.: No-load rotation speed (3) Grinding horsepower H (PS) HP = N
The cutting width t5 changes depending on the condition of the welding bead. Therefore, the required torque for grinding changes (turning,
The rotation speed will change depending on the characteristics of the motor.

Now, on the characteristic diagram shown in Fig. 6, we are grinding at a torque T and a rotation speed N such that the horsepower becomes the maximum H□, and the pipe has advanced by Δψ in the circumferential direction.

During cutting and grinding, t1 → t x (tz > t
l), b1 → bz (bt '>b2'), the torque and rotational speed are T□ → THI N →
Becomes NL. If the load torque T□ exceeds the stall torque Ts of the air motor, a situation will occur in which the number of rotations N→0 and the near motor 140 rotations will stop.

Therefore, in this embodiment, the rotational speed N of the tachogenerator 15 attached to the rear of the air motor 14 is sampled and detected using a micron computer, and if N□-N2>0, it is determined that the load is large and the transmission is performed. If NL-N) is 0, it is determined that the load is small and the feed speed (2) is increased.

With the above control, grinding is performed in the range from the horsepower H2 to the maximum horsepower H1 shown in FIG.

The above is the nine-speed feed control.

FIG. 17 is a block diagram of a system for performing the above-mentioned cutting depth control and feed speed control in this embodiment.

The Zollock diagram of this control system is almost the same as that shown in FIG. 8, so its explanation will be omitted here.

FIG. 18 shows the entire control system of the device of this embodiment. The same reference numerals as those previously used indicate the same three parts. The control device is composed of a microcomputer 60, a control circuit 61, and an operation panel 62. DC motor 9 used in this device,
12.39 is connected to the microcomputer 60 via the motor control circuit 58.

Further, the potentiometers 11, 13, 41, 42 and the light emitter/receiver are connected to a microcomputer 60 via an A/D converter 59. There are two operating modes for this device: manual and automatic. In the case of automatic, the operation mode is largely controlled by a control program stored in the internal memory of the microcomputer 0.

The overall operation of the apparatus of this embodiment will be explained with reference to the flowchart of FIG. 19. First, the shape detection device 37.1, the drive device 8, and the grinding device 17 are fixed on the carriage 6. Whetstone 1
Return 6' to the origin 1. The shape detection device 37 measures the shape of the welding bead surface over the entire circumference, and from the starting point,
The height of the weld bead and the distance between the surface of the pipe 10 and the rail surface of the guide ring 2 at each position in the circumferential direction are calculated by the microcomputer 60. If there is no need to continue grinding in this state, the work ends there. If not, the grinding direction is determined, the grinding wheel 16' is positioned at the grinding starting point, and then grinding is started. At this time, the depth of cut is controlled based on the measurement data of the shape detection device 37, and the rotation speed of the air motor 14 is sampled and detected by the microcomputer 60, thereby controlling the grinding load fluctuation so that it does not exceed a certain range. While grinding.

Furthermore, since the amount of wear of the grindstone 16' is also measured in-process by the microcomputer 60, if the amount of wear becomes greater than the set amount, the depth of cut value is corrected. While performing the above-mentioned careful control, grinding is carried out until the bead height reaches a predetermined amount Hc of remaining machining.

〔Effect of the invention〕

According to the present invention, even if the centers of the piping and the guide ring are not necessarily aligned accurately, or even if the piping itself is distorted and the guide ring has mechanical tolerances, the horizontal, vertical or diagonal position of the piping can be adjusted. It is possible to efficiently finish the weld bead to a constant height in the circumferential direction of the pipe while always applying appropriate cutting (grinding) pressure in all positions and maintaining the load on the motor within an appropriate range. can be made smaller.

[Brief explanation of drawings]

Figure 1 is a front view of Embodiment I of the present invention. Figure 2 is an installation diagram of the magnetic sensor and price cutter in Figure 1, Figure 3 is a characteristic diagram of the magnetic sensor, and Figure 4 is a guide ring and piping. FIG. 5 is an explanatory diagram of the cutting control in Example I, FIG. 6 is a characteristic diagram of the air motor, and FIG.
The figure is a diagram explaining the influence of intermittent cutting of the milling cutter on load detection, Figure 8 is a professional line diagram of depth of cut control and feed speed control in Example 1, and Figure 9 is the overall control of the same example. System diagram, FIG. 10 is a cutting flowchart of the same embodiment, FIG. 11 is a front view of embodiment H of the present invention, and FIG. 12 is a cutting flowchart of the same embodiment.
A schematic side view of the shape detection device in the figure, FIG. 13 is a front cross-sectional view of the grinding device in FIG. 11, and an explanatory diagram of the relative positional relationship between the idle link and the piping. A block diagram of feed speed control, FIG. 18 is an overall control system diagram of the embodiment (2), and FIG. 19 is a grinding flowchart of the same embodiment. DESCRIPTION OF SYMBOLS 1... Piping, 2... Guide ring, 6... Carriage, 8... Drive device, 9... DC motor, 1
1... Potentiometer, 12... DC motor,
13... Potentiometer, 14... Air motor,
15... Tacho generator, 16... Milling cutter, 16'... Grinding wheel, 17... Cutting (grinding) device, 18... Magnetic sensor, 21... Magnifier, 22...
Φ converter, 23... microcomputer, 24...
...Control circuit, 25...Operation panel, 37...Shape detection device, 39...DC-C, -ta, 41.42...
- Potentiometer, 56... Emitter, 57... Light receiver, 58... Amplifier, 59... A/D converter, 60... Microcomputer, 61... Control device, 62. ··Operation board. Figure 1 Figure 16 = ii ("jj1lsf) -1-1 (Lf) Figure 19 Continuation of page 1 @ Inventor Koji Saito @ Inventor Ya 1) Eldest son [phase] Inventor Noboru Umehara ■Inventor Ori 1) Motoyasu 3-1-1 Saiwai-cho, Hitachi City Hitachi, Ltd. Hitachi Factory 3-1-1 Saiwai-cho, Hitachi City Hitachi, Ltd. Hitachi Factory 3-1-1 Saiwai-cho, Hitachi City No. Hitachi, Ltd. Hitachi Factory

Claims (1)

[Claims] 1. A ring-shaped guide rail clamped onto a pipe, a carriage driven around the circumference of the pipe on the guide rail, a carriage drive device fixed to the carriage, and a weld bead of the pipe. In a pipe welding bead finishing apparatus comprising a cutter or grindstone and a cutting or grinding device mounted on the carriage, a measuring means on the carriage measures the distance between the cutter or grindstone and the pipe surface; A depth of cut control means for cutting a cutter or grindstone to a predetermined height from the piping surface based on the measured output, a load detection means for detecting the cutting or grinding load, and a load detection means for controlling the load to a predetermined range based on the output of the load detection means. A piping weld bead finishing device characterized in that a feed speed control means is provided for controlling the feed speed of the cutter or the grindstone so that the feed speed of the cutter or the grindstone is maintained at the same rate as the guide rail. 2. The pipe according to claim 1, further comprising a measuring means for measuring the height of the pipe weld bead from the pipe surface, and the cutting depth control is corrected based on the output of the measuring means. Weld bead finishing equipment. 3. Claims 1 or 2 further comprising means for detecting the amount of wear of the grindstone, and correcting the depth of cut control with respect to the wear of the grindstone based on the output of the means. piping weld bead finishing equipment.