关键词: CT80钢级, 连续油气管, 国产

Abstract: Coiled tubing is a tubular product for oil and gas, which can be curled repeatedly and coiled around a reel with a length of several kilometers. As compared to conventional tubing, coiled tubing has some unique advantages, such as convenient transportation and high efficiency, and is extensively used for various no-killing operations such as acidizing, fracturing and sand washing. It is called as “universal tubing.” Based on the service environment for coiled tubing and taking into account weldability, anti-buckling performance, anti-fatigue performance and corrosion resistance of coiled tubing, CNPC Baoji Petroleum Steel Pipe Company Limited has designed and developed new-type coiled tubing using low-carbon micro-alloy heat-rolled steel band. It has created a set of coiled tubing technology with its independent intellectual property right, including steel strip docking, transformation heat treatment of inclined welding seams, high-stability and high-precision HFW shaping welding, heat treatment of whole tube body and heat treatment of welding. It has also established the first coiled tubing production line in Asia and developed CT80 coiled tubing (the yield strength ≥ 552 MPa and the tensile strength ≥ 621 MPa).The assessment result and field application indicated that all the indexes of the product, such as strength, plasticity, corrosion resistance and service life, reached the advanced international level.

Key words: CT80 steel grade, coiled tubing, China-made