Negative pulse pressure wave generator and well cementing device

Abstract

The invention discloses a negative pulse pressure wave generator and further provides a well cementing device comprising the negative pulse pressure wave generator. The negative pulse pressure wave generator comprises a base, a pressure wave generating mechanism and a first outer cylinder. A power part is arranged on the base and connected with the pressure wave generating mechanism; the first outer cylinder sleeves the power part and the pressure wave generating mechanism and is fixedly connected with the base; a sealing piece is arranged between the pressure wave generating mechanism and thefirst outer cylinder; the pressure wave generating mechanism comprises a top cover, a bottom plate and a second outer cylinder; the top cover, the bottom plate and the second outer cylinder hermetically define an air pressure cabin, the side wall of the second outer cylinder is provided with a first through hole and a sealing shaft, and the first through hole is sealed by the sealing shaft; and the power part can drive the pressure wave generating mechanism to move in the axial direction of the first outer cylinder, when the air pressure cabin is located outside the first outer cylinder, thesealing shaft can move into the second outer cylinder under the action of the internal and external pressure difference of the air pressure cabin, and accordingly the air pressure cabin is opened. Thenegative pulse pressure wave generator is good in reliability and high in positioning precision.

Description

technical field [0001] The invention relates to the technical field of drilling, in particular to a negative pulse pressure wave generator and a well cementing device containing the negative pulse pressure wave generator. Background technique [0002] Cementing operation is an important link in the process of oil and gas exploration and development. Poor quality of cementing operation will shorten the life of the oil well, and cause huge loss of life and property, environmental pollution and other problems. [0003] The cementing plug plays the role of isolating the cement slurry and drilling fluid during the cementing operation. The mechanism of action is that the cementing plug moves to the bottom of the casing under the pressure of the drilling fluid, and the cement in the casing will With the movement of the rubber plug, it is pushed into the casing-wellbore annulus. When the rubber plug reaches the bottom of the casing, the rubber plug will form a seal with the bottom o...

AI Technical Summary

Problems solved by technology

The problem with this judgment method is: on the one hand, this process is single, and you may miss it if you are not careful during the observation process; Problems with small pressure changes that cannot be effectively monitored, rendering them useless

It should be noted that the system uses a large number of electronic components, and the sealing requirements are extremely strict during use, especially as the depth of the wellbore increases, the pressure will increase. At the same time, the system uses radio frequency as the signal The way of transmitting and receiving is greatly affected by the environment at the bottom of the well; finally, the system uses the pressure wave generated by the explosion of explosives as the pressure wave generating mechanism. The control is also very strict, the large amount will damage the seal, and the small amount will not form an effective pressure wave, so the cementing plug system is slightly complicated, and there are big problems in reliability during use

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