PTQ Q4 2023 Issue

Technology in Action

Results As soon as the research team verified the prototype robot through a pipeline mounted on a test skid and made nec- essary corrections, the robot was put to test at two CTCI construction sites in Taiwan and India. In the former test, the robot successfully passed through the 12m pipeline comprised of horizontal, vertical, and elbow sections, overcoming the problem of gravity support during vertical crawling. The welding slag inside the pipeline was success- fully removed by the robot. The latter test took place at an LNG regasification construction site, where the robot was placed inside a 25m, ø12in submerged combustion vapo- riser pipeline. The test began with the robot starting at a 90° elbow open entrance before crawling horizontally through a con- trol valve and a magnetic flow transmitter and climbing ver - tically to the top. As with the former test, the robot could overcome its own weight and cable weight when climbing. Through real-time images, the engineer had a clear picture of the pipeline interior and successfully removed the debris stuck in the ball valve cavity and the weld joint’s inner wall. Overall, test results show that the LNG pipeline cleaning robot achieves a 95% cleaning rate, which is far superior to the conventional air-blowing technique. By applying the pipeline cleaning robot, the likelihood of LNG leakage due to valve damage is expected to drop by 50%, bringing value to owners and operators. CTCI For more information, visit: www.ctci.com/e-newsletter/ EN/474/technology/article-01.html

CTCI develops LNG pipeline cleaning robot

Challenge When an LNG terminal reaches mechanical completion, it is common to use compressed air to blow away the debris inside the LNG pipelines. Debris usually comes in the form of swarf, welding spatter, oxides, slags, and dust. However, the compressed air-blowing method can only help remove 60% of the debris. In part, this is due to the non-stream- lined nature of pipe fittings and the low wind surface area of some of the debris. Failure to remove debris from the LNG pipelines may cause the debris to accumulate in the valve seats, which in turn damages the valve and results in potential LNG leakage. Conventional pipeline robots equipped with brushes and high-pressure water jets are mostly designed for sewer and air duct cleaning and can allow only horizontal or ver- tical movement. For LNG terminal pipeline systems made up of horizontal and vertical pipelines, elbows, tee fittings, and reducers, conventional pipeline robots clearly cannot CTCI worked with Cheng Shiu University to successfully develop a pipeline cleaning robot specifically for LNG pipe - lines. Suitable for ø10-14in pipelines with a wall thickness of S100, the 14kg robot sized 80cm x 20cm x 20cm mim- ics worm-like movement. It can penetrate the pipeline as far as 50m under wired remote-control mode at a design do the job. Solution

speed of more than 15m per minute. Movement is achieved through a PLC-based control sys- tem. The robot body is driven by a DC brushless motor and controlled by PID differential mode. The rub- ber power wheels can expand, collapse, and adhere to the inner pipeline walls, thus allowing the robot to effortlessly crawl inside, climb up to 90°, and move 6m vertically. With the omnidirectional imaging lens attached to the robot, a video image is taken at the frame rate of 30 fps and a resolution of 960H, offering the operator a real-time and clear picture of the pipeline’s interior condition. Once the opera- tor pinpoints the debris, it may be brushed, blown, or sucked away (suction allows 5g of debris up to 3mm in size).

Cleaning a section of pipeline using a robot

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PTQ Q4 2023