61.66 Days! Drilling An 8,000-meter Vertical Well Section in The Tarim Basin Breaks China’s Fastest Record

How many days will it take to drill an oil and gas well more than 8,000 meters deep? The answer given by the Tarim Basin is: 61.66 days.

On January 17, Well Manshen 805 was drilled to a completion depth of 8,123 meters. Photo by Li Tao

The fastest well drilled to a depth of more than 8,000 meters is the Tarim Oilfield Manshen 805 Well. It is located in Shaya County, in the hinterland of the Taklimakan Desert. It was drilled by the 90019 drilling team of the Bazhou Branch of China Petroleum Corporation Western Drilling Engineering Co., Ltd. On February 3, reporters came here to explore the technological power within the well.

"On January 17, Well Manshen 805 was drilled to a depth of 8,123 meters in the third opening, which took 61.66 days, saving 22 days of construction time, and set a domestic record for the shortest period for drilling a vertical well section to a depth of 8,000 meters." Western Drilling Bazhou Branch 1 Senior engineer Zhang Hao said that the designed well depth of Well Manshen 805 is 9,255 meters. The casing and cementing construction of the third drive has just been completed and the completion of the third drive is in progress.

Well Manshen 805 has difficulties such as a long open hole section, multiple stratigraphic sequences, easy to get stuck, easy to leak, and easy to tilt, making the construction difficult. In recent years, the average cycle for drilling to 8,000 meters in the full-depth block has remained at 120 to 150 days. The 90019 drilling team took 61.66 days to break through 8,000 meters. This enriches the template for speeding up ultra-deep well drilling in the full-depth block and provides domestic ultra-deep well drilling speed-up technology. Learn from advanced ideas and experiences.

The cadres and employees of the drilling team worked together to keep an eye on the operation and carry out casing running operations. Photo by Li Tao

In order to complete the construction tasks of this well with high quality and efficiency, Western Drilling Bazhou Branch strengthened source design and process management, implemented all-round and multi-dimensional safety measures to achieve rapid and efficient construction in the entire well section, and at the same time insisted on command and assistance from the front. First-level engineers are stationed at the well to provide guidance, provide all-round assistance to the well team, and promptly solve difficulties and problems encountered during production operations.

Before construction, Western Drilling Bazhou Branch combined data from adjacent wells and focused on drilling problems encountered in adjacent wells to formulate practical speed-increasing measures in advance. During the actual drilling process, the advantages of geological engineering integration were fully utilized, geological predictions were made in advance, and drilling parameters and drill bit types were selected in a targeted manner.

The 90019 drilling team, which drills the full-depth 805 well, holds technical morning meetings every day, communicates with the project team personnel in a timely manner, discusses and analyzes the construction difficulties and possible abnormal conditions that day, and continuously optimizes the construction plan and refines the technology based on the actual conditions on site. Measures should be taken to improve the optimal and fast drilling model to achieve the purpose of increasing speed and efficiency.

In order to ensure the smooth progress of casing running construction and the quality of casing entering into the well, the drilling team employees are cleaning the casing threads to ensure the safety and efficiency of casing running. Photo by Li Tao

During the construction of the third drilling of Well Manshen 805, a pre-curved drill tool assembly was used with a non-planar toothed crystalline diamond composite drill bit. The footage in a single trip was 2145 meters, and the mechanical drilling speed reached 10.16 meters/hour, setting a new record for the highest footage in a single trip in the Manshen block. 

"Well Manshen 805 will enter the next construction period on the eve of the Spring Festival. The 90019 drilling team will further refine the winter safety production measures, intensify post inspections, keep a close eye on key links and key construction, organize production in a planned way, and strive for another A new record." said Yang Xinlong, platform manager of the 90019 drilling team of Western Drilling Bazhou Branch.