CS239839B1 - Method of chesking of underground pipeline during its operation - Google Patents

Abstract

Integrity control, piping acoustic emission is a progressive method. For Pipes where periodic checks should be carried out from the safety point of view to avoid accidents that have a greater economic impact impact a podium-based solution that lies in being on the ducts will be placed before burial the ear canal, the end of the end contact pad for, attaching acoustic probe emissions.

Description

The present invention relates to the issue of checking the integrity of a pipeline by acoustic emission stored in the ground during its operation.

The need to inspect the pipeline by acoustic emission buried in the ground has arisen in pipelines where there is a low frequency of failure, which does not imply the need to shut it down. On the other hand, however, damage to the pipeline can result in considerable financial losses, life threatening threats when (this runs through built-up areas around roads and the like).

For the inspection of such pipelines, a methodology has been developed which requires uneconomical digging of the pipeline parts and possible removal of this part for inspection. When checking the integrity of the pipeline by acoustic emission of AE, we do not excavate the pipeline and allow the linear location of the defect site.

The AE sensing probes are placed on the pipeline at a certain distance and the pipeline is then stimulated to activate any defects present in the pipeline material. The acoustic emission indicates the presence of these defects and the approximate location of their occurrence is determined by processing the signals in the imaging apparatus.

The problem with the inspection is the location of the probes on the other pipe. For this purpose, boreholes shall be made at the appropriate points down to the pipeline so that a probe or horn can be applied. In such preparations for measurement, it may happen that the borehole may be routed outside the pipeline, or the pipeline may be damaged. .

A further disadvantage of such a procedure is that it is not possible to control the seating of the probe, respectively. the ear canal to the duct and thus the sensitivity of the sensors placed on the duct can have considerable deviations. This may result in incorrect evaluation of the measured results.

The above-mentioned disadvantages are largely eliminated by the method according to the invention, which consists in attaching to the pipeline, prior to placement in the ground, a firm, non-detachable connection, in the form of ropes, terminating above the ground surface with a seating pad .

In particular, the advantages of the method according to the invention are that for pipes which require regular inspection or which are of particular importance, their integrity can be checked by means of acoustic emission without any excavation works with great accuracy and reliability.

Ropes of the same cross-section are preferably used as ear canals, one end of which is connected to the pipe before being buried in the ground by means of a fixed, non-detachable connection. The ends of the ropes can be connected by brazing, stabbing and the like. Such a connection method ensures good contact and positively affects the stability of the sensitivity of the sensors and the accuracy of the inspection. At the same length of the ear canal, the sensitivity of the sensors will be influenced only by the quality of the connection of the sensor to the ends of the ear canal, equipped with a seating plate, which is located on the terrain surface.

In the case of a change in the length of the ear canal for undulating terrain and the like, it will be easy to calibrate the change in sensitivity using an acoustic emission simulator. The flexibility of the ear canal in the form of a rope ensures its adaptability to possible soil shifts without affecting the sensitivity of the sensor. In addition to ropes, wires, rods or flanges may be used as ear canals.

Pipe integrity checks are faster, measurements are well reproducible and can be performed cyclically.

The pipe is firmly connected to the ear canal, which is led above the surface of the terrain. At its end there is a seating plate for attaching the acoustic emission probe. The most suitable place for soldering the rope to the pipeline is in the middle between the yard adjacent circumferential welds, but at least 1 m from the circumferential weld.

The optimum distance for adjacent ear canals is 50 to 60 meters. The controller goes through the acoustic emission measuring device and the probe, which is connected to the ear canal via the seat plate and records acoustic signals on the device, which are comprehensively evaluated after the control has been transferred.

One auditory duct per measurement is used for control, but if localization of the acoustic source is needed, emissions can be used at the same time two auditory ducts per measurement. The critical point is then determined from the time difference between the capture of the acoustic emission signals.

The method can be applied wherever periodic inspections in the case of produlktovovovov are necessary for safety and accident, which would cause more economic damage.

Claims (1)

A method for checking the integrity of a pipe laid in the ground by acoustic emission during operation, characterized in that the inventive horns, preferably in the form of ropes, placed above the surface of the terrain, terminated by a contact surface, are fixed to the pipe prior to its laying in the ground. acoustic emission apparatus probes.