The history of coiled tubing--From China National Offshore Oil

The tubing can be bent, like a snake, and because of seamless welding, the name of the cooiled tubing.(The short name is CT )

During the Second World War,The Allies successfully crossed the English channel using 17 special metal pipelines to cross the sea.These special submarine pipelines are the forerunners of the coiled tubing.In the early 1960s, the technology developed on the basis of coiled tubing was highly effective in western oil well repairing operations.Fifty years later,coiled tubing operations are very popular in the world oil and gas industry.

The coiled tubing is wound around a large diameter drum and is slanted together by a number of steel bands. In addition to the early oil gathering and transportation function, it is now widely used in oil field drilling, completion of well, fracturing, acidification, drainage, testing of oil, oil recovery and gas, well repairing and plugging of gathering and transporting pipelines. Because there is a wide range of applications, coiled tubing and its operation and equipment is vividly called the "universal operating machine".

Technology is developing faster in the west than in the east

It was not too late for China to introduce coiled tubing. In 1978, the sichuan petroleum administration of China introduced the first coiled tubing operating machine from Bonn corporation of the United States.

We have a lot of coiled tubing machine. There are 2,089 in the world, and we have over 160.

However, in terms of application, coiled tubing is still insufficient for horizontal Wells and unconventional gas development,In particular,the sea operations compared with foreign countries still have a large gap.

Compared with conventional drilling, continuous tubing has a short operating cycle and a low accident rate. Continuous tubing drilling can reduce the cost by 25% to 40% and has great advantages in directional drilling and unbalanced drilling.

It has been proved that the application of coiled tubing technology in horizontal well drilling, workover and production increase is conducive to the realization of simple, fast, safe and reliable construction process, the improvement of operating efficiency, the reduction of labor intensity and operating cost, and the reduction of damage to the formation environment.

Coiled tubing is a crutch to deep water

In addition to complete coiled tubing drilling operations, compared with foreign coiled tubing operations, domestic multistage fracturing and coiled tubing in long horizontal Wells have reached international standards, but the technology is still a "newcomer" in the ocean.

In terms of breadth and scope of application,"newcomer" is not equal to blank space. In fact, CNOOC(China national offshore oil corporation) has long bought coiled tubing equipment from abroad. 

2012 was a trough for the oil and gas industry and an opportunity to apply the coiled tubing. Compared with drilling new Wells, using coiled tubing workover can reduce the cost. It will be more convenient and reliable to drill, rescue Wells or environmental sensitive areas on offshore platforms or floating production facilities without permanent installation of drilling equipment.

Coiled tubing not only has the characteristics of large outer diameter and long pipe body, but also is very intelligent

After years of development, coiled tubing has formed a complete and functional industry. The operation process has expanded from simple cleaning and fishing operations in the early days to large-scale fracturing, sandblasting and perforation, logging and drilling.

At present, there are a number of ultra-large-diameter coiled tubing equipment operating in the world's high-end coiled tubing operation area, which can realize sandblasting and fracturing with large discharge coiled tubing.Large diameter and over length coiled tubing also promote the innovation and upgrade of mining mode. The coiled tubing makes the wellhead site more concentrated, covering a smaller area and covering a wider range of the well.

The depth, pressure and sulphur content of the oil well in China's sea area are different. They are designed together with the roller and injection head of the connecting pipe equipment, and become the key factors affecting the oil pipe life.Each operation of coiled tubing will experience at least 6 times of bending, and finding the best combination point of working condition and equipment design is the key to fine coiled tubing design.

Information and intelligence means that the coiled tubing is highly automated, and workers can make remote diagnosis and decision on the operation process through integrated control.