RU2293315C1 - Department of intrapipe flaw detector - Google Patents

Abstract

FIELD: magnetic flaw detection.

SUBSTANCE: intrapipe flaw detector can be used for magnetic flaw detection of steel pipelines due to investigation of dissipation magnetic fields by means of probes placed inside pipes. Department of intrapipe flaw detector has cylindrical case with removable caps and at least one engage unit. Department is additionally provided with member for transmission of longitudinal force between engage units mounted coaxially to case; transmission member is made of two discs. Case with removable caps is disposed between the discs. Discs of member for transmitting longitudinal forces are connected together by pulling members; any disc is connected to corresponding engage unit. Case of department is provided with members which prevents its shift at radial direction in relation to mentioned longitudinal force transmission unit.

EFFECT: less load on cap of case and case.

8 cl, 6 dwg

Description

The invention relates to the field of magnetic flaw detection of steel pipelines by examining magnetic fields of scattering using probes moving inside the pipe and consisting of several sections.

In-pipe flaw detectors moving inside the pipe, as a rule, consist of several separate sections interconnected by couplers. When flaw detectors move, quite large dynamic forces arise during acceleration of the flaw detector, as well as during jerks occurring during its movement due to changes in the geometry of the pipeline. The design of the individual sections of the flaw detector and the coupling devices must withstand these dynamic loads. Particular requirements are imposed on the tightness of the enclosures of the flaw detector sections, inside the housings of which instruments and equipment are located, since the flaw detector is in the pipe under the influence of environmental pressure, which can be quite large. The tightness of the housings of these sections is ensured, as a rule, due to the strengthening of the fastenings of the covers of the housing, to which longitudinal forces are applied from the coupling devices, transmitted further through the housing.

In US Pat. No. 6190090, “Apparatus for Use in a Pipeline,” IPC B 08 B 009/055, publication February 20, 2001, 6,370,721, a longitudinal force from the coupling device is transmitted through the attachment of the housing cover and the housing.

In the international application WO 98/43062 "Inspection device with a positioning system and inertial navigation" the longitudinal force from the coupling device is also transmitted to the housing through the fastening of the housing cover.

All the solutions considered have a common feature - the fastening of the housing cover must ensure the tightness of the housing not only against the pressure of the medium, but also withstand the longitudinal forces arising from the movement of the flaw detector in the pipe.

Strengthening the fastening of the cover to the housing to compensate for longitudinal forces is not always possible, especially for flaw detectors working in pipes of small diameter, since the useful volume of the instrument compartment is reduced due to reinforcement of the fastening.

The claimed invention solves the problem of unloading the cover of the housing and the housing from the transmission of longitudinal forces between the coupling devices, reduces the requirements for fastening the cover and the housing and thereby allows to increase the usable volume inside the housing.

The inventive section of the in-line flaw detector contains a cylindrical body with removable covers and at least one coupling device. The section is additionally equipped with a longitudinal force transmission element between the couplers mounted axially to the housing and made of two discs, between which the housing is located with removable covers. The disks of the longitudinal force transmission element are interconnected by tightening elements, and each disk is also connected to a corresponding coupling device. The section housing is provided with elements preventing its displacement in the radial direction relative to the aforementioned longitudinal force transmission element.

Due to the fact that the longitudinal force is transmitted not through the housing cover, but through the longitudinal force transmission element, the housing cover can be attached to it by elements of a smaller diameter, thereby the housing can be made thinner and the net volume inside the housing increases. During the movement of the section, the dynamic force is transmitted to the disks connected by tightening elements, and not the housing cover. An additional effect arises due to the fact that the disks and the tightening elements not only transmit a longitudinal force, but also press the covers to the case during the installation of the section. Thus, the requirements for attaching the cover to the housing can be further reduced.

In special cases, the tightening element can be made in the form of a stud with nuts or a bolt with a nut.

The elements that prevent the housing from moving in the radial direction can be longitudinal holes in the wall of the housing, designed to pass the said tightening elements.

Elements that prevent the housing from moving in the radial direction can be tides with holes made on the outer surface of the housing. These tides are elements that prevent the housing from shifting in the radial direction, as well as for skipping said tightening elements.

In special cases, the execution of the disk can be flat, convex-concave and can also be made integral with the coupling device.

The invention is illustrated by drawings.

Figure 1 shows a vertical sectional view of an in-line flaw detector section with one embodiment of a longitudinal force transmission member.

Figure 2 is the same side view of the section.

In Fig 3 - element-wise composition of the section on one side of the housing.

Figure 4 - one of the embodiments of the section assembly.

Figure 5 is another embodiment of a longitudinal force transmission member.

Figure 6 is the same side view.

The in-line flaw detector section (FIGS. 1 and 2) contains a cylindrical body 1 with removable covers 2 and a coupling device 3. The section is also equipped with a longitudinal force transmission element 4 made of two discs 5, between which the housing 1 with removable covers 2. Disks 5 interconnected by tightening elements 6. The housing 1 of the section is provided with holes 10, which are clearly visible in Fig.3. The tightening elements 4 in FIGS. 1 and 2 are the studs 7. The covers 2 are attached to the housing 1 through the gasket 13 also by means of the studs passed through the holes in the housing 1 and fixed with nuts 17 (FIG. 2). The sections are joined to each other in the pipe 15 by means of the hitch 16.

Figure 1-3 shows an example of a section with a tightening elements 6 in the form of pins 7 and with a coupling device 3, made integral with the disk 5.

In special cases, the execution of the disks may have a different shape. For example, they can be flat or convex-concave, in the form of a hollow cup. In addition, the disk rim does not necessarily have a round shape, for example, as in FIGS. 5 and 6, the disk is made with tides, or may have a star shape. In addition, there may be a hole in the disc to reduce the mass of the disc.

Figure 4 shows an example of the execution of the section with the tightening elements 6 in the form of bolts 8 and with the coupling device 3, made separately from the disk 5.

Figures 5 and 6 show an example of a section with tides 11 on the housing 1, into the openings of which the tightening elements 6 are inserted, in this case bolts 8 with a nut 14.

In preparation for operation, the coupling device (FIGS. 1-6) is assembled as follows. First, the covers 2 of the housing 1 are attached and tightened with bolts or studs. Then, the disks 5 are installed and pulled together by means of the tightening elements 6, studs 7 or bolts 8. In this case, the longitudinal force from the coupling device 3, when sections pass through the pipe, is transmitted through the disks 5 and the tightening elements. Thus, the housing of the section 1 and the attachment elements of the cover 2 to the housing 1 work without these efforts.

Claims (8)

1. Section of an in-line flaw detector comprising a cylindrical body with removable covers and at least one coupling device, characterized in that the section is further provided with a longitudinal force transmission element between the coupling devices, mounted axially to the housing and made of two disks, between which said case with removable covers, disks are interconnected by tightening elements, each disk is also connected to the corresponding coupling device, and said case is bzhen elements preventing its displacement in a radial direction relative to said longitudinal force transmission element. 2. Section according to claim 1, characterized in that the said tightening element is made in the form of a stud with nuts. 3. Section according to claim 1, characterized in that said tightening element is made in the form of a bolt with a nut. 4. The section according to claim 1, characterized in that the wall of the said cylindrical body is provided with longitudinal holes, which are elements that prevent the housing from shifting in the radial direction, and are designed to pass said tightening elements. 5. The section according to claim 1, characterized in that on the outer surface of the said body there are tides with holes that are elements that prevent the body from shifting in the radial direction and for skipping said tightening elements. 6. Section according to claim 1, characterized in that the said disks are made flat. 7. Section according to claim 1, characterized in that the said disks are made convex-concave. 8. Section according to claim 1, characterized in that the said disks are made integral with the coupling device.

Images