DE3301329C2 - Method for ultrasonic testing of tapered threads provided on pipe ends as well as device for its implementation - Google Patents

Abstract

One method for ultrasonic testing of pipe threads consists in introducing ultrasonic vibrations into the body of a pipe 3 on the end face 1 of the tapered thread 2 of a pipe 3 and scanning them along the circumferential line of the end 1 of the tapered thread 2 of the pipe 3. The half-value opening angle .r of a bundle of ultrasonic vibrations is the tightening angle. of the taper thread 2 of the pipe 3 is the same. In the device which is used to carry out the above-mentioned method, a driver group 9 for driving the tube 3 on the guide 6 contains rollers 10 and 11 arranged perpendicular to the guide 6. The roller 10, which is arranged on the tapered thread 2 of the tube 3, is rigidly connected to the guide 6 and is conical with a tightening angle of the cone, which is the tightening angle. of the thread 2 of the tube 3 is the same. The rollers 11 are cylindrical and are movably kinematically connected to the conical roller 10 via the guide 6 for driving the end 1 of the conical thread 2 of the pipe 3.

Description

characterized in that

- The half-value opening angle (gp _r ) of the introduced bundle of ultrasonic vibrations is chosen to be equal to the tightening angle {φ) of the conical thread, with an edge ray of the bundle propagating parallel to the bottom of the conical thread.

2. Device for ultrasonic testing of tapered threads provided on pipe ends for Implementation of the method according to claim 1, with a guide (6) on which one of the pipe end (3) associated driver group (9) and a piezo transducer (5) are provided, characterized in that

- That the driver group (9) consists of rollers (10, 11) arranged vertically on the guide (6) consists,

- That one (10) of these rollers is conical, rolls off the conical thread (2) and is rigidly connected to the guide (6), the tightening angle of the roller corresponding to the tightening angle (φ) of the conical thread (2),

- That the other rollers (11) are cylindrical roll on the pipe wall facing away from the thread and in the guide (6) to change the relative distance are mounted displaceably to the conical roller (10),

- That the conical roller (10) and the cylindrical Rollers (11) for pressing against the conical thread (2) or against the pipe wall are connected via springs (18) and

- That the piezo transducer (5) on a slide (22) which can be adjusted and fixed on the guide (6) is attached to generate vibrations in the longitudinal direction of the pipe end (3).

The invention relates to a method and a device for ultrasonic testing of pipe ends provided Taper threads according to the preamble of claim 1 or 2.

It is a method for ultrasonic testing of threaded connections known (SU-Urheberschein 02 849), which consists in the fact that one in the threaded connection introduces ultrasonic vibrations at two different angles, the angle and the Depth of the defect formation can be calculated according to the number of turns of the thread, which in the present Angles of the introduction of ultrasonic vibrations with the error are covered. The procedure mentioned is difficult to carry out because it involves the introduction of ultrasonic vibrations by means of a piezo transducer at an angle, a retuning of the piezo transducer for the introduction of ultrasonic vibrations at a different angle, a reading of the number of turns covered with a fault of the thread on the screen of a defect scope at the two angles of the introduction of ultrasonic vibrations as well as the determination of the angle and the depth of the defect formation according to this information.

There is also a method for ultrasonic testing of cylindrical threads is known in which a diverging Beam of ultrasonic vibrations is introduced at the face of a pipe thread. As a result The divergence of the beam gives signals from the threads on the display screen of the device, which can only be eliminated by reducing the sensitivity of the device, but what the test and makes it difficult to evaluate the signals (Krautkrämer; materials testing with ultrasound; 4th edition; 1980; Pages 367 to 372).

It is also a method for ultrasonic testing of tapered threads on pipe ends accordingly the preamble of claim 1 known, in which the ultrasonic vibrations at the Front face of the tapered thread introduced and scanned along the circumference of the face of the tapered thread (see, for example, the anthology of scientific and technical papers on »Machine and Petroleum Equipment«, H. II, Moscow, WNIIOENG, 1973, page 22).

As additional signals are generated by the threads, the accuracy of the test is reduced.

DE-GM 70 34 725 and US-PS 38 44 164 are devices for testing welding phases of a Known circular seam, in which a sensor head with rollers of the circular seam rolling on the pipe edge by turning the pipe or by moving it itself

It is also a device for ultrasonic testing of tapered threads provided on pipe ends according to FIG the preamble of claim 2 known that a guide with a piezo transducer, a nozzle for supplying a contact liquid and a driver group rolling on the pipe wall (SU Copyright Certificate No. 4 73 802). In the device mentioned, the driver group is in the form of Levers with rollers and a movable handle with fork-shaped tie rods formed at its ends, which are arranged in guide grooves of supporting jaws and interact with the levers. With help However, this device can only use the piezo transducer on the surface of tubes with a diameter up to 146 mm.

The invention is based on the object of the method and the device of the generic type to be further developed in such a way that to increase the test accuracy only the signals originating from an error received or that pipes with a wall thickness of up to 90 mm with exact alignment of the direction relative to the pipe thread can be checked.

According to the method, this task is described in the characterizing part of claim 1.

33 Ol

related measures as well as according to the device described in the characterizing part of claim 2 Features solved.

The inventive method makes it possible that no signals from the threads thanks to one of the Angle of inclination of the thread corresponding choice of the opening angle of the one emitted by the Wandle- Ray are received. The only thing that appears on the screen of the device is that of a defect or error outgoing signal, whereby the test accuracy can be increased.

With the help of the device according to the invention, tapered threads of pipes with a wall thickness of up to 90 mm can be checked. At the same time, the accuracy of the test can be increased and accurate alignment the device can be guaranteed relative to the thread of the pipe.

The invention is explained in more detail below with reference to the drawings. It shows

Fig. 1 shows an embodiment of the device for ultrasonic testing of provided at pipe ends Taper thread, which is used to carry out the procedure, in longitudinal section,

F i g. 2 shows the embodiment of FIG. 1 in the direction of arrow A and F i g. 3 in the direction of arrow B.

The method according to the invention for ultrasonic testing of conical threads provided on pipe ends 3 consists in that ultrasonic vibrations are introduced into the pipe body on the end face 1 (FIG. 1) of the conical thread 2. The half-value opening angle φ _{Γ of} the introduced bundle of ultrasonic vibrations corresponds to the tightening angle φ of the tapered thread 2 of the pipe 3. Then the introduced ultrasonic vibrations are scanned over the circumferential length of the face 1 of the tapered thread 2 and the ultrasonic vibrations reflected by a flaw in the tapered thread are received, after which the flaw is then assessed.

The half-value opening _{angle φ τ of} the introduced bundle of ultrasonic vibrations, which corresponds to the tightening angle φ of the conical thread 2 of the pipe 3, is determined according to the known formula, according to which the half-value opening _{angle φ Γ of} the bundle of ultrasonic vibrations is deliberately assumed to be equal to the tightening angle φ of the conical thread 2 provided at the end of the pipe will:

df =

0.61 C.

Sin φ '

50

where:

φ Tightening angle of the taper thread (degrees);

d diameter of the piezo element of the piezo transducer (mm);

/ Working frequency of ultrasonic vibrations, (MHz);

C Speed of propagation of ultrasonic vibrations in the pipe body (m / sec) (see BAK eo Gurevich, IN Ermolov "Ultrasonic testing of welds" Kiev, Verlag "Technik", 1972, p. 14).

Under this condition, the ultrasonic vibrations are planted parallel to the bottom of the thread of the taper thread 2 continues, and if there is a defect in the taper thread, the ultrasonic vibrations a pulse is generated which carries information about the presence of the fault

The device for ultrasonic testing of tapered threads provided on pipe ends, with which the above-described method is carried out, comprises a U-shaped guide 6 (FIG. 2) with a piezo transducer 5, nozzle 7 arranged on this, for supplying a contact fluid via hoses 8 and a driver group 9 (Fig. 1). The driver group 9, which rolls on the pipe wall, contains on the guide 6 three rollers 10 and U arranged perpendicular to it. The one roller 10 which is arranged on the tapered thread 2 is rigidly connected to the guide 6 and is conical according to the tightening angle φ of the taper thread 2 of the tube 3 is formed.

The two other rollers 11 (Fig. 1, 2) are cylindrical formed, roll on the pipe wall facing away from the conical thread and are with the conical Roller 10 is movably connected via guide 6.

The conical roller 10 is connected by means of a bush 13 and an axle shaft 14 attached to a bracket 12. The console 12 is in turn attached to the guide 6. On the side opposite the fastening point of the console 12, there is a handle 16 on the guide 6 attached by means of a pin 15. The cylindrical rollers 11 are attached to a bracket 17 which is attached to the Guide 6 is movably arranged. The console 17 (Fig. 2) is connected to the console 12 by means of springs 18, and their movement over the guide 6 is limited by a fixing strip 19. At the point of attachment the console 17 (Fig. 1) opposite side is a handle 21 on the guide 6 by means a pin 20 attached.

The piezo transducer 5 is on a slide 22, which is movable on the guide 6 and relative to the conical Roller 10 is adjustably attached, arranged and generates 3 vibrations in the longitudinal direction of the pipe end.

The piezo transducer 5 itself contains the above-mentioned piezo element 4, which is attached to a defectoscope (not shown) is connected by means of a cable 23. The piezo element 4 is glued to a damper 24 and housed in the housing 25. In the carriage 22 is a socket 26 with a protective device 27 and a Joint 28 installed, in which the transducer 5 is provided. There are two fixing screws on the carriage 22 (FIG. 3) 29 and 30 are provided, one of which is a fixing screw 29 for fixing the carriage 22 relative to the conical roller 10 and the other fixing screw 30 for adjusting the angle for the introduction of ultrasonic vibrations into the tubular body at the end face 1 of the tapered thread 2 serves.

The springs 18 are attached to the guide 6 and to the bracket 17 by means of supports 31.

The device for ultrasonic testing of tapered threads provided on pipe ends, which are used for Is used to carry out the procedure, has the following mode of action:

By means of handles 16 and 21 (FIG. 1), the consoles 12 and 17, on which a conical roller 10 and cylindrical rollers 11 are attached, for receiving the end 1 of the taper thread 2 of the tube 3 pushed apart. Rolls 10 and 11 become pressed by means of the springs 18, because the console 17 with the cylindrical rollers 11 and the handle 21 via the U-shaped guide 6 relative to the conical

33 Ol

gene roller 10 is movably arranged. The console 12 with the conical roller 10 is U-shaped Guide 6 rigidly connected. The conical roller 10 is on the thread 2 and the roller 11 screwed on the cylindrical part of the tube, d. H. when checking the nipple thread part of the pipe the conical roller 10 is located on the external thread of the pipe when testing the socket thread part but on the internal thread of the pipe. The converter 5 is located on the end face 1 of the Taper thread 2. Hoses 8 and nozzles 7 (Fig. 2) are used in the zone of ultrasonic vibrations, which are emitted by the piezo transducer 5, a contact liquid is supplied.

Then the piezo transducer 5 (Fi g. 1) is attached to the end face 1 of the tapered thread in such a way that on no signals from the floor appear on the screen of the defectoscope (not shown in the figure) of the thread turn of the taper thread 2 originate. Since the carriage 22 (FIG. 3) with the converter 5 by means of the screw 29 is determined relative to the conical roller 10, the emitted by the transducer 5 are Ultrasonic vibrations when the device moves over the circumference of the tapered thread 2 (Fig. 1) always pass at the same distance from the bottom of the thread of the taper thread 2. This increases the accuracy of the test.

The accuracy of the test is also increased in that the bundling diagram of the piezo transducer 5 is selected in such a way that the half-value opening angle Ordern corresponds to the tightening angle φ of the thread 2. Under these conditions, the ultrasonic vibrations are propagated at the pipe end 3 parallel to the bottom of the thread turn of the thread 2. The calculations are based on the above formula:

df =

0.61 · C
Sin φ

pipe threads of all type sizes are used because the cylindrical rollers 11 (Fig. 1), which with the conical roller 10 are kinematically connected, are pushed away from this roller to a length can, which is equal to the length of the U-shaped guide 6, which, in turn, depending on the wall thickness of the pipe end 3 is selected.

For testing drill pipes with different taper thread angles, a corresponding tapered Use roll 10.

The device for the ultrasonic testing of pipe taper threads, which is used to carry out the method serves, allows the testing of tapered drill pipe threads of all types because of the extendable roller the wall thicknesses of pipes of all types can be waived.

The device mentioned has a simple design and is operationally reliable. Furthermore can Pipes with production defects are sorted out in good time and thus the technical and economic parameters be increased when drilling holes.

35

40

carried out.

Since in the vicinity of the piezoelectric element 4, the ultrasonic vibrations propagate almost without divergence, behind this there is a mechanical delay in Form of the material layer of the housing 25 of the transducer 5 is provided, the thickness of which in accordance with the near zone (Fresnel zone) is selected. Plant at the same time the ultrasonic vibrations, starting at the end face 1 of the taper thread 2 in the pipe body, are parallel to the bottom of the thread turn of the taper thread 2 continued.

During the test of the threaded part, the transducer 5 is located in the pipe even if the pipe walls are different the same distance from the bottom of the thread turn of the thread 2, because it is relative to the conical roller 10 is found, which rolls on the surface of the taper thread 2 during the test

When the face of the tapered thread 2 is worn and when it deviates from the vertical Position relative to the longitudinal axis of the pipe end 3 is the angle for the introduction of the ultrasonic vibrations changed. The transducer can adjust the angle at which the vibrations are introduced 5 swing in this case in the longitudinal planes of the pipe end 3, since it is arranged on a joint 28 that is fastened in the slide 22 by means of a screw 30 (FIG. 3).

The device used to carry out the method can be used to test conical drilling tools 2 sheets of drawings

Claims (1)

33 Ol 329 claims: 1. Procedure for ultrasonic testing of pipe ends provided taper threads, in which - Ultrasonic vibrations initiated on the face of the ball screw, - The ultrasonic vibrations are scanned along the circumference of the face of the tapered thread and - which reflected from an error in the taper thread Ultrasonic vibrations are received to assess the fault,