The Development Of Coiled Tubing Online Testing System

Coiled tubing has played an important role in oil and natural gas exploitation inborehole operation, it has been applied in a wider range. The safety problems in theusing process of coiled tubing have been more and more prominent, due to thecomplexity of the underground work conditions. Evaluating the security through real-time monitoring the damage in the operation process of coiled tubing, make it possiblefor the operation department to predict and deal with the problem produced in theoperation of the coiled tubing. Meanwhile, it has practical significance on extending theservice life of coiled tubing, saving production cost, improving operation efficiency,ensuring the safe using in the working spot and avoiding the occurrence of majoraccidents.An on-line nondestructive testing technology to test defects and ovality of thecoiled tubing was studied according to the micro magnetic testing and eddy currentranging technology, as well as the actual requirements of coiled tubing in fieldoperation. The overall scheme of the coiled tubing detection system was designed inline with the technical parameters requirements. The detection system consists of tubedefect detection unit, ovality measurement unit, mechanical structure unit and softwareunit. Based on the micro magnetic detecting technology, the tube defect detection unitcan realize the position, qualitative and quantitative analysis of defect by analyzing theanomaly characteristics of the magnetic field of the defect. Multiple eddy currentdistance sensor were arranged in the same section. The measuring algorithm was alsodesigned to calculate of the ovality value according to the variation of the measureddistance. The mechanical structure unit was designed in the chute type to adaptmeasurement requirements of different specifications of pipe diameters. The softwaresystem was compiled with VB6.0and c#language with a friendly operation interface,to implement two-dimensional imaging of defect signal.The coiled tubing testing prototype was developed through debugging of completeset of hard and soft system. The indoor simulation test and field test of the prototypewere conducted. The test results showed that the prototype is of simple operation, stablerunning and high sensitivity. The resolution of corrosion measurement can achieve up to8%of the wall thickness, and the ovality measurement precision is1%.The researchwill promote the level of domestic coiled tubing site online testing instrument.