A positioning device and positioning method in a pipeline based on pipeline segment length and pipeline connector detection

Abstract

The invention discloses a pipeline inner positioning device based on a pipeline section length and pipeline connector detection and a positioning method thereof, and belongs to the technical field ofpipeline mapping. The device and the method aim to solve the problems of low positioning and orienting precision of a small-diameter pipeline detection positioning system. According to the device, a main body is composed of a sealed cavity and is sequentially provided with a data storage unit, a data processing unit, an MEMS strapdown inertial measurement unit and a power supply module from left to right; and the two ends of the outer wall of the main body are symmetrically provided with a plurality of mileage wheels and supporting wheels at equal intervals, pipeline defect detection sensors are arranged on the parts, between the mileage wheels and the corresponding supporting wheels, of the outer wall of the main body, and the pipeline defect detection sensors, the mileage wheels and thesupporting wheels are isolated by plastic sealing rings. In addition, a complex continuous wavelet transformation pipeline connector is adopted in the positioning method based on the pipeline sectionlength and the pipeline connector detection, on one hand, azimuth angle and pitching angle error correction are provided for the pipeline positioning system on a straight pipeline section, and on theother hand, a pipeline section length information base is combined to provide the position error correction for the pipeline positioning system so that accurate positioning of pipeline defects can beachieved.

Description

technical field [0001] The invention relates to a positioning device and a positioning method in a pipeline, in particular to a positioning device and a positioning method in a pipeline based on the detection of the length of a pipeline section and a pipeline connector, and belongs to the technical field of pipeline surveying and mapping. Background technique [0002] Some of the pipelines laid in the early years have reached or exceeded their service life, and dangerous accidents such as leakage and explosion often occur. The resulting environmental pollution, economic problems and personal safety threats are extremely serious. In addition, natural disasters such as landslides, mudslides, and crustal movements can also cause deformation or even rupture of pipelines. At present, the detection device in the pipeline has become the most effective tool for periodic detection of various pipelines because it is not limited by external terrain conditions for pipeline defect detect...

AI Technical Summary

Problems solved by technology

However, the orientation angle error and position error divergence of the inertial assisted positioning system composed of small-volume and low-precision MEMS are relatively large. Error and Position Error Correction

The traditional magnetic orientation angle detection sensor has a large error in the small diameter pipeline due to the influence of the inner diameter of the pipeline and the environment inside the pipeline, so it is difficult to provide accurate orientation angle information for the pipeline detection and positioning system

In addition, when searching for relevant information, the previous invention patents hardly involved the surface marker point position correction method, and the paper "Development of Ground Marker for Magnetic Flux Leakage Detection of Oil and Gas Pipeline Defects" published in 2012 used the surface marker detection based on weak magnetic detection The PIG position information is obtained from the time passed by the PIG below it and used to correct the positioning error of the inertial-assisted pipeline detection and positioning system, thereby limiting the position error of defect detection within the range of 1-2m

However, this method is not suitable for steel pipes and other occasions where the internal magnetic field is variable and the magnetic signal detection and processing are complicated.

At the same time, the pre-installation of surface magnetic markers will be affected by the external terrain of the pipeline (ocean, hillside, urban buildings, etc.), and the detection of long pipelines requires many magnetic markers, which is expensive

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