4286 meters! Major Breakthrough in Drilling of Ultra-long Shale Gas Horizontal Wells in China

On October 27, Sinopec announced that the Jiaoye 18-S12HF well in Fuling Shale Gas Field of Jianghan Oilfield of Sinopec was successfully completed with a drilling depth of 7161 meters, of which the horizontal section was 4286 meters long and the "one-trip drilling" footage in the horizontal section was 4225 meters long, setting a new record for the longest horizontal section and the longest horizontal section, marking a major breakthrough in shale gas drilling in China, it will strongly drive China's shale gas to achieve efficient development.

Shale gas is an unconventional gas reservoir, also known as "artificial gas reservoir". Shale gas needs to be crushed to allow gas to come out. It is recognized as a world-class problem by the industry, and horizontal well technology is particularly critical. "Ultra-long horizontal well" refers to a horizontal well with a horizontal section length of more than 3000 meters. Due to many technical problems such as difficulty in carrying cuttings, complex force of drilling tools, high risk of well wall collapse, it is difficult to realize in mountain shale gas drilling, and has always been a difficulty in efficient development of shale gas in China.

As a national shale gas demonstration area, Fuling shale gas field has made every effort to tackle the drilling technology of ultra-long horizontal wells for shale gas. Sinopec has successfully installed "eyes" on the drill bit through independent research and development of three-dimensional visualization comprehensive geosteering technology. Using the stored massive geological data, Sinopec can adjust the trajectory of the drill bit at any time, so that the drill bit can "accelerate straight" and "drift over bend" in the underground palace, and pass through the high-quality reservoir like "pancake" at high speed like "greedy snake. At present, Sinopec's horizontal well technology can drill more than 4 kilometers in the error range of less than 5 meters.

At the same time, the innovation of the formation of ultra-long horizontal well key equipment and tools, ultra-long horizontal well friction reduction, ultra-long horizontal well drilling parameters dynamic optimization technology, to achieve from "not hit" to "hit fast, hit accurate" a major leap. At present, the average drilling cycle of Fuling shale gas has dropped from more than 90 days to more than 40 days, the shortest drilling cycle is only 25.58 days, and the drilling rate of excellent reservoir is more than 96%.

Since Fuling shale gas field was put into development and construction, it has innovated shale gas exploration and development theory, formed six core technologies, realized efficient development of 3500-meter shallow gas reservoir and effective development of 3500-4000-meter gas reservoir, pioneered China's shale gas three-dimensional development technology, and the recovery rate of three-dimensional development zone reached the international advanced level. Up to now, the cumulative proven reserves are nearly 900 billion cubic meters, the cumulative built production capacity is 15 billion cubic meters, and the cumulative output has exceeded 47 billion cubic meters. It has sent clean energy to more than 70 large and medium-sized cities in 6 provinces and 2 cities along the Yangtze River Economic Belt, benefiting thousands of enterprises, Nearly 0.2 billion residents.

Source:CCTV News ClientAuthor: CCTV reporter Zhang Wei editor: Chen Zhouying