JP2002096010A - Device for sealing coating film defective - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a device for sealing a coating film defective, which is capable of applying a mark by which it is clearly recognized in a post process to be the defective due to the deficiency of the film thickness when it is detected to be the defective due to the deficiency of the film thickness as a result of measuring the film thickness of the coating film about a pipe inside surface of which is coated. SOLUTION: The device for sealing the coating film defective is composed of a rotation supporting means 10 having a rotary roller 12 supporting the pipe freely rotatably, a coating material (a) in a coating material vessel 31a and a coating unit 30 for coating by rotatably driving a transferring lever 34 having a coating roller 32 with an air cylinder 35 to be in contact with the pipe P and transferring and is formed so that a special mark is applied on the whole periphery of the outside of the pipe while rotating the rotary roller 12 by a control signal that the coating film is the defective due to the deficiency of film thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating film defective marking apparatus for reworking a pipe determined to be defective by measuring a coating film applied to the inner surface of a pipe such as a cast iron pipe.

[0002]

2. Description of the Related Art Ductile cast iron pipes (hereinafter abbreviated as iron pipes) and the like are generally coated with an epoxy resin powder on the inner surface of the iron pipe for rust prevention treatment. This coating thickness is
In the S standard (JIS G 5528), the thickness is set to 0.3 mm or more, and the minimum film thickness is specified, but the maximum film thickness is not specified, and the optimal maximum film thickness is economically (minimum necessary paint). Has been adopted. Therefore, it is necessary to measure the coating film thickness and secure an appropriate coating film thickness.

[0003] As a device for measuring whether or not the coating film thickness is appropriate, an electromagnetic film thickness sensor is generally used. This electromagnetic film thickness sensor consists of a coil wound around a ferromagnetic metal rod, and when a predetermined current is passed through this coil to bring the rod tip close to the surface of the painted metal body,
Utilizing that the self-inductance of the coil increases or decreases according to the distance from the surface, the change is detected by a detection circuit to measure the thickness of the film. As one of the film thickness gauges using a film thickness sensor utilizing such a measurement principle, a "single-pole, two-point adjustable electromagnetic film thickness meter" is known.

In general, this thickness gauge is used by an inspector holding the hand and pressing the tip of a rod of the thickness gauge against a surface to be measured. For this reason, the film thickness meter is limited to measurement on the surface of the object to be measured, and can be used only within an allowable range that can be reached by an inspector. In particular, a painted surface applied as a rust preventive treatment to the inner surface of a steel pipe, a cast iron pipe, or the like is inaccessible and cannot be measured at all in a depth that cannot be visually recognized. For this reason, Japanese Patent Application Laid-Open No. H10-30041 discloses a film thickness measuring method and apparatus capable of coping with the measurement of the coating film on the inner surface of the tube.
No. 2 proposes this.

[0005] The method for measuring the film thickness according to this patent publication is
A film thickness gauge having a film thickness sensor similar to the film thickness sensor based on the above measurement principle is attached to the tip of the robot arm so that it can be freely moved in the depth direction inside the tube and in a direction perpendicular thereto. The tip is pressed at right angles to the surface inside the tube, and the power of the film thickness measurement circuit is turned on to activate the circuit based on the change in the relative positional relationship between the rod tip and the surface, and the film thickness is measured.

[0006]

By the way, the film thickness measuring means disclosed in the above-mentioned patent publication is an excellent film thickness measuring means in that the coating film thickness on the inner surface of the tube can be automatically measured without manual operation. However, there are various problems in actually measuring the coating film thickness on the inner surface of the pipe using this film thickness measuring means.
For example, how to specifically arrange the film thickness measuring means with respect to the pipe, and when measuring at a predetermined position in the longitudinal direction of the inner surface of the pipe, measurement is performed at a plurality of locations along the inner circumferential surface of the pipe at that position. Seems to be common, and in that case, it is necessary to rotate the tube or the film thickness sensor.

With respect to such a problem, a tube is horizontally supported by a rotatable support means so as to be rotatable, and a movable carriage is disposed at both ends in the longitudinal direction of the tube, and a horizontal arm is mounted on the carriage via a lifting means. The end of the horizontal arm is attached to the end of this horizontal arm, and a film thickness gauge having a two-point adjustment type film thickness sensor is attached to the end of the horizontal arm. A measuring method and an apparatus for measuring a film thickness by bringing a thickness sensor into contact with a surface to be measured in a tube are conceivable.

According to such a method and apparatus, the pipe is stopped at a predetermined length position in the pipe while rotating the pipe by a predetermined angle, and each time the film thickness sensor is brought into contact with the surface to be measured, and a plurality of pipes are formed along the inner circumference of the pipe. The coating thickness at each position can be continuously measured with high accuracy at each location. At this time, if the film thickness is less than the required minimum thickness (for example, 0.3 mm) when the film thickness is measured at each of a plurality of locations, the film thickness is naturally not normal at the measurement location. , The tube is detected to be defective.

Therefore, when such a defective product due to insufficient film thickness is detected, the defective product is given some kind of seal, and when the defective product is collected as a defective product, the defective product due to the insufficient coating film thickness is obtained. It is desirable to seal a mark so that something can be visually identified at a glance. However, in the past, the thickness inspection of the coating film on the inner circumference of the pipe was performed only by the inspector's hand at a limited, small length position from both ends of the pipe to the position where the hand-held thickness gauge could enter. At present, sufficient film thickness cannot be measured, and at present, when a defective product due to insufficient film thickness is found, the inspector paints the paint by hand. In the case of manual sealing, since the stamped portion is not constant, there is a problem that the stamp is overlooked in a later process or the stamp is forgotten.

In view of the above problems, the present invention measures the thickness of a coating film on the inner surface of a pipe, and when it is determined that the defective product is insufficient due to insufficient film thickness, the defective product due to insufficient film thickness. It is an object of the present invention to provide a coating film defective product marking device capable of applying a mark that can clearly recognize in a later step.

[0011]

According to the present invention, there is provided a rotating support means for rotatably supporting a pipe having an inner surface coated thereon, and a coating material which is provided in close proximity to the outer periphery of the pipe. And a control signal based on a detection signal of a defective product by measuring the coating film thickness, and sending a control signal to each means, and driving the rotation support means to rotate the pipe, thereby operating the coating means on the outer periphery of the pipe. This was a marking device for improper coating film that applied paint.

According to the apparatus for marking a defective defective paint film, a characteristic mark is applied to the outer periphery of the tube. In this case, it is premised that the coating film thickness measuring device in the preceding process detects that the coating film thickness is insufficient, and a control signal based on the detection signal is transmitted to the driving unit of the marking device. When the control signal is sent, the respective drive units of the rotation support means and the painting means operate to apply the paint to the pipe determined to be defective.

At this time, since the pipe is rotated by the rotation of the rotation supporting means supporting the pipe, when the pipe is rotated while the tip of the coating means is in contact with the outer circumference, the rotation causes the entire circumference of the pipe to be rotated. A mark can be applied to the circumference, and when such a mark is attached, when reprocessing is performed in a later process, the tube with this mark is recognized as a defective product due to insufficient coating film thickness. can do.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic layout diagram including devices in steps before and after a coating film defective product marking device of an embodiment provided in a coating film thickness measuring device. The illustrated coating film defective product marking device A is an epoxy resin powder coating device (not shown) that coats an inner surface of a ductile cast iron tube (hereinafter, referred to as an iron tube) manufactured by an upstream cast iron tube manufacturing device (not shown). After body coating, a large number of iron pipes arranged side by side on the stock table E are first inspected for pinholes by the pinhole inspection device B, and then the coating film for measuring whether the coating thickness on the inner surface is normal is measured. It is provided within the installation range of the thickness measuring device C.

A defective pipe sorting / conveying apparatus D is provided downstream of the stamping apparatus A shown in the figure. The stock table E, the pinhole inspection device B, the coating film thickness measurement device C,
Another conveying device C ₀ is provided for conveying the iron pipe over below the defective tube sorting conveying device D between the respective devices. Reference symbol R is a return route of the reworked product.

FIG. 2 is an enlarged plan view of the coating film thickness measuring device C.
Figure 4 shows an enlarged side view. The coating film defective product marking device A is a device independent of the coating film thickness measuring device C, but is provided within the installation range of the measuring device C and has a close relationship with each other. The illustrated measuring device C includes three iron pipes P, P, and P sent in parallel after completing the pinhole inspection in the previous process.
And a film thickness meter having a film thickness sensor at the end of an arm provided on a carriage to measure the film thickness of the surface to be measured on the inner surface of the iron pipe. The film thickness measuring means 20 is provided in a pair on the left and right. The rotation support means 10 includes three iron pipes P, P,
Each of P is provided so as to be rotatably supported by each of three pairs of rotating rollers 12, 12. As shown in FIG. 5, the rotation support means 10 on one side (left side in FIG. 2) transmits the output of the motor 13 as a drive unit to the two rotation rollers 12, 12 via transmission means 14 using a number of sprockets and chains. Transfer to 3 sets and rotate while supporting the tube. Rotation support means 10 on the opposite side (right side in FIG. 2)
There is no drive unit, and the rotation roller 12 rotates by rotation of the iron pipe P. Carriage 1 carrying device C ₀ between the pair of rotary support means 10 and 10 are provided so as to travel on a rail 2 with wheels 3, it came transported by lifting with support 4 of the upper part of the carriage iron pipe The iron pipe P is mounted on the rotation supporting means 10 by lowering the P.

The coating film defective marking device A shares the rotation support means 10 with the coating film thickness measuring device C, and
Is provided as a coating means.
The marking unit 30 stores the paint a in a paint tank 31 a which is provided in a paint case 31 so as to be freely mounted.
A transfer means having an application roller 32 for transferring the paint a from the a to the outer peripheral surface of the iron pipe P is provided. The transfer means rotatably supports a transfer lever 34 via a rotation shaft on a support lever 33a provided at the upper end of the support member 33, and rotatably supports the application roller 32 at the tip of the transfer lever 34, and the rear end. Is connected to the end of the piston rod 35a of the air cylinder 35.

As shown in FIG. 4, the support member 33 is a member vertically attached to the side wall of the support base 11 of the rotary support means 10. If the transfer means can be supported without being supported by the support base 11, It may be fixed by another method. The air cylinder 35 is provided on the support bracket 33 with respect to the support member 33.
5b rotatably supported. Also, the transfer lever 34
Is provided with a length necessary to transfer the paint a from the inside of the paint tank 31a to the outer periphery of the iron pipe P by rotating the tip from the point supported by the support lever 33a by the advance and retreat of the piston rod 35a of the air cylinder 35.

The above-mentioned coating film thickness measuring device C is a device for measuring whether or not the coating film thickness is within a specified range in the preceding process of the coating defective marking device A, and detects a detection signal by measuring a defective product. Since the apparatus has a close relationship, its configuration and operation will be briefly described below. As described above, the rotation supporting means 10 is also used for this measuring device C, but has already been described, so that the following description will be made from the film thickness measuring means.

In the example shown in FIG.
Three sets of film thickness measurement units 22 are provided on a trolley 21. The carriage 21 is provided with two sets of driving sources on a fixed base 21a, an elevating base 21b thereon, and running wheels below the fixed base 21a. One of the driving sources is for self-running by rotating wheels, and the other is for raising and lowering the elevator 21b.

The film thickness measuring unit 22 on the elevator 21b
Is constituted by attaching a film thickness gauge 27 to the tip of an arm 26 held via an angle adjusting means 25 on an elevating guide 24 attached to a bracket 23 fixed to an elevating table 21b.
The elevating guide 24 is formed so that a linear guide is provided along the vertical end of the bracket 23, and the moving member 24a is moved up and down by the upper cylinder. A horizontal member 25a of the angle adjusting means 25 is attached to an end of the moving member 24a. The base of the arm 26 is rotatably mounted at an intermediate position of the horizontal member 25a, and the angle of the arm 26 with respect to the horizontal member 25a is adjusted and set by a spring and a screw rod. An elevating means is formed by the elevating table 21b and the elevating guide 24.

The structure of the film thickness meter 27 is basically the same as that disclosed in
In the film thickness gauge 27, an electromagnetic induction type film thickness probe 28 comprising a magnetic core made of a ferromagnetic material and a coil wound therearound is provided in the film thickness meter 27 near the tip thereof. It has. The coating film thickness on the surface to be measured is measured based on the change in the self-inductance of the coil of the film thickness probe 28. The film thickness signal measured by the film thickness probe 28 is sent to a measurement circuit, where it is converted into a binary signal.
Further, it is sent to a computer of an external main measuring circuit (not shown), and the main measuring circuit measures the film thickness. The film thickness by the film thickness probe 28 is measured based on a two-point adjustment type measurement principle.

When the film thickness is measured by the film thickness meter 27, when three iron pipes P, P, P are respectively placed on the rotating rollers 12, 12 of the support tables 11, 11, the stand-by position is set at the stand-by position. The trolley 21 of the film thickness measuring means 20 which has been operated is brought close to both ends of the iron tube P, and the film thickness meter 27 at the end of the arm 26 is inserted into the tube.
Stop at a predetermined length position. At this time, the protruding end of the thickness gauge 27 is inserted along the length direction of the iron pipe at a position at least 20 mm or more away from the surface to be measured in the iron pipe. When the diameter of the pipe relative to the surface to be measured in the iron pipe changes greatly from, for example, a large pipe to a small pipe, the lift 21b of the carriage 21 is previously adjusted so as to be at the predetermined distance position, and the adjustment distance is adjusted. The holding height of the arm 26 is adjusted by the elevating guide 24 in the small range. When the thickness gauge 27 is inserted on the surface to be measured in the iron tube as described above, the arm 26 is further lowered by the elevating guide 24 so that the protruding end of the thickness gauge 27 is perpendicular to the surface to be measured. In contact with each other and measure the film thickness.

The iron pipes P, P,
The coating film thickness of each of the inner surfaces of P is measured, and when the main measurement circuit detects that the coating film thickness of any of the iron pipes P is insufficient, a control signal based on the detection signal is sent to the coating film defective marking device A. And the rotation support means 10 and the marking unit 30 as the coating means are operated. Stamping unit 3
A value of 0 activates a unit to which a control signal for detecting a defective product has been sent out of the three units. The activated marking unit 30 is applied to the application roller 3 by the air cylinder 35.
2 and the application roller 3 in the paint tank 31a during standby.
2 is transferred and adhered to the outer periphery of the iron pipe P.

At the same time, the iron pipes P, P, P
Since the three sets of the zero rotation rollers 12 are rotated, the paint is applied to the iron pipe P corresponding to the activated marking unit 30. In this case, the paint is applied to the entire outer periphery of the iron pipe P by rotating the iron pipe P. The fact that such a mark indicating a defective product due to the coating of the entire circumference of the paint is due to a defect in the coating film thickness may be caused by other reasons (for example, a pin failure) when the defective iron tube is later collected and reprocessed. This is useful for distinguishing and recognizing defects such as defects due to hole detection and defects due to bending.

Since the transfer means employs the air cylinder 35 in the driving section, the application roller 32 is pressed against the iron pipe P by the elasticity of air even when the diameter of the iron pipe P is different. The coating roller 32 can be surely brought into close contact with the surface of the iron pipe P to transfer the paint. In the illustrated example, the diameter of the iron tube P is 75, 100, 1
Five types of 50, 200, and 250 mmφ are targeted.

The marking unit 30 as a coating means can be variously modified in addition to the above embodiment. For example, the application roller 32 may be lifted by a vertical rod from the inside of the paint tank 31a and brought into contact with the outer periphery of the iron pipe P.

[0028]

As described in detail above, in the coating film defective marking apparatus of the present invention, the lack of the coating film thickness on the inner surface of the pipe in the previous process is compared with the pipe rotatably supported by the rotary support means. A unique mark is attached to the entire circumference of the outer periphery of the pipe by contacting the tip of the coating means operated by a control signal based on the detected result, which indicates that the product is defective due to insufficient coating film thickness. The mark can be attached and identified by a simple marking device attached to the coating film thickness measuring device, and the effect that it is convenient for processing in a subsequent process can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic layout diagram in the vicinity of a coating film thickness measuring device of a cast iron pipe production line.

FIG. 2 is a plan view and a side view of a coating film thickness measuring device.

FIG. 3 is a longitudinal sectional view of the coating film defective product marking device viewed from the arrow III-III in FIG. 2;

FIG. 4 is a perspective view of a main part of a device for marking a defective coating film.

FIG. 5 is an enlarged cross-sectional view taken along line VV in FIG. 2;

FIG. 6 is a side view of a film thickness measuring means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rotation support means 11 Support stand 12 Rotary roller 13 Motor 14 Transmission means 20 Film thickness measuring means 21 Cart 21b Lifting platform 22 Film thickness measuring unit 23 Bracket 24 Lifting guide 25 Angle adjusting means 26 Arm 27 Film thickness meter 28 Film thickness sensor 30 Marking unit 31 Paint case 32 Application roller 33 Support member 34 Transfer lever 35 Air cylinder

Claims (3)

[Claims] 1. A defective product comprising a rotation supporting means for rotatably supporting a pipe having an inner surface coated thereon, and a coating means for applying a coating material to the outer periphery of the pipe in close proximity to the rotation supporting means. A defective coating film marking apparatus in which a control signal based on the detection signal is sent to each of the above-mentioned means, and the rotation supporting means is driven to rotate the pipe to apply the paint to the outer periphery of the pipe by operating the coating means. 2. The imprinting of a defective coating film according to claim 1, wherein the rotation support means is configured to rotatably support the tube by rotating the rotation roller while contacting the rotation support means with the outer periphery of the tube. apparatus. 3. A coating means for applying the coating material in a coating tank to an application roller, rotating a rotary lever having an application roller, and bringing the application roller into contact with the outer periphery of the pipe to transfer and apply the coating material. 3. The marking device for defective coating film according to claim 1, wherein