Horizontal well drilling and fracturing completion string and its technology

Abstract

The invention relates to the field of oil and gas field exploration and development, in particular to a once drilling fracturing completion pipe string of a horizontal well and a drilling fracturing completion technology for reservoir reform in the oil and gas field exploration and development. The pipe string at least comprises an oil pipe (2) connected in a sleeve (1) in a sleeving manner, and is characterized in that a waterpower spray gun (3) is arranged at the undermost end of the oil pipe (2); spray gun eyelets are formed at the side part of the waterpower spray gun (3); a ball seat (5) capable of placing a steel ball (6) is arranged at the bottom of the waterpower spray gun (3); and sleeve valves (7) and oil pipe valves (8) are arranged at wellhead ends of the sleeve (1) and the oil pipe (2) respectively. According to the pipe string and the technology, various procedures of the horizontal well can be completed by once drilling; a well control risk and the times of replacing a drilling tool are reduced; an acceleration progress can be increased; an acceleration effect is obvious; a packer and the waterpower spray gun can be saved; the abrasion of the oil pipe is reduced; a utilization ratio is increased; and the development cost of the horizontal well is lowered.

Description

technical field [0001] The invention relates to the field of oil and gas field exploration and development, in particular to a horizontal well drilling and fracturing completion pipe string for reservoir reconstruction in oil and gas field exploration and development and a technology thereof. Background technique [0002] At present, domestic horizontal well staged fracturing technologies include bridge plug fracturing, packer fracturing, sand plug fracturing and liquid rubber plug fracturing, etc., and packer staged fracturing technology is the main technology. . The packer isolation fracturing process also includes drag fracturing with a single injector with a bottom packer, and staged fracturing with a double injector with a bottom packer, such as PSK multi-stage hydraulic jet staged fracturing. Although PSK multi-stage hydraulic jet fracturing can achieve about 10 stages of construction in one trip, which greatly saves the number of trips, but between each construction ...

AI Technical Summary

Problems solved by technology

[0005] 1. Between each construction layer, blowout should be carried out for 2-5 hours. After the pressure in the well is released, the backflush is about half an hour before the wellhead can be lifted up to carry out the construction of the next layer. During the pressure Fracture equipment waits for 2-5 hours, and at most 1-3 intervals can be constructed every day. The construction speed is slow, which has become one of the main restrictive factors for the development of low-permeability oil and gas reservoirs.

[0006] 2. When fracturing each layer, all fracturing sand fluid must be sprayed from the spray gun before entering the construction layer. The life of the spray gun is limited, and it can only fracture 2-3 layers of more than 90 cubic meters of sand at most.

Even if the PSK multi-stage layered construction technology is used, it cannot meet the requirements of the multi-stage staged fracturing technology for horizontal wells. When the construction interval in the well reaches about 20 intervals, at least 2-3 trips of the pipe string need to be replaced, resulting in well control risks and risks. Environmental pollution caused by spraying; fracturing construction has to wait for 2-3 days, which is also one of the main factors restricting the speed-up of production technology

[0007] 3. Each horizontal well needs to be drilled once for flushing, about 2-3 times for hydraulic jet fracturing, and once for sand washing, and at least 4-5 times for each well to complete the construction. Operation, the operation team bears a huge workload of manpower, the pollution of the returned liquid to the environment, and the risk of well control during tripping

[0008] 4. Since there are several packers for layered fracturing connected to the construction tools in the well, it is not possible to inject large displacement (3-10 cubic meters per minute) into the annular space, and cannot meet the technological requirements of large-scale volume fracturing

The maximum construction displacement in the tubing can only meet the construction volume of 2.5-3 cubic meters per minute. Under this construction displacement, the tubing used in each construction string can only be used 2-3 times before it needs to be scrapped, which increases the cost of horizontal wells. Development costs

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