5results about How to "Low starting pressure" patented technology

The present invention provides a true triaxial loading mechanism for simulating the dynamics of ultra-deep drilling cores, comprising a reaction loading frame, a first principal stress loading assembly, a second principal stress loading assembly and a third principal stress loading assembly, wherein a high-pressure fluid loading chamber extending along the third principal stress direction is constructed inside the reaction loading frame, and a core sample is arranged in the high-pressure fluid loading chamber, wherein the first principal stress loading assembly, the second principal stress loading assembly and the third principal stress loading assembly provide principal stress loading for the core sample in three principal stress directions, and the third principal stress loading assembly is integrated in the reaction loading frame, and the third principal stress loading assembly blocks the high-pressure fluid loading chamber, so that the high-pressure fluid loading chamber is formed into an ultra-high pressure chamber. The present invention can simulate the dynamic true triaxial loading conditions of ultra-deep drilling cores in deep geological environments during the true triaxial loading process of the core sample, so as to obtain stress-strain information of the dynamic disturbance full destruction process.

The invention discloses a water control type workover fluid and a preparation method thereof. The water control type workover fluid is prepared from the following components in parts by weight: 2 parts of a clay stabilizer, 0.2-1 part of a high-temperature chelating agent, 0.5-1 part of a corrosion inhibition bactericide, 1-2 parts of a waterproof locking agent, 5 parts of a phase change agent and 100 parts of filtered seawater. The method comprises the following steps: filtering the filtered seawater until suspended particles are less than 30 microns in standard value, sequentially adding a clay stabilizer, a high-temperature chelating agent, a corrosion inhibition bactericide, a water blocking prevention agent and a phase change agent, and uniformly stirring to obtain the water control type workover fluid. After the workover fluid enters a reservoir, the oil phase starting pressure can be reduced, the oil-water interfacial tension can be reduced, the effect of inhibiting water content rising after well workover is achieved, the workover fluid can be matched with different field operation types, and the recovery period of an oil well can be shortened.

The invention provides a gas collecting valve and method for recovering casing associated gas in an oil well shaft and having blowout prevention capacity, one end of a central pipe is connected with an upper joint, the other end of the central pipe is connected with a lower joint, and a sliding sleeve is mounted on the outer wall of the central pipe; the annular metal framework is arranged on the lower connector in a sleeving mode and fixedly connected with the lower connector, and the leather cup is arranged on the annular metal framework. The leather cup clings to the inner wall of the sliding sleeve; the rubber surface of the leather cup and the metal surface of the inner wall of the sliding sleeve form an annular contraction sealing surface, and the upper and lower spaces of the sealing surface are respectively communicated with the exhaust port and the air inlet to form a differential pressure type control switch; a sealing ring is arranged at the joint of the sliding sleeve and the central pipe; a differential pressure type sliding switch is formed among the sliding sleeve, the center pipe and the sealing ring, and therefore the problems that a ground gas collecting valve is large in installation workload, prone to freezing and blocking in winter, short in service life, small in gas collecting amount, large in sealing point number, prone to oil gas leakage and high in safety and environmental protection risk are effectively solved.

This utility model discloses a sewage sedimentation tank that is easy to clean, including a sedimentation tank body. The bottom structure of the sedimentation tank body is a V-shaped tank bottom, and a sludge discharge trough is opened in the middle of the V-shaped tank bottom. An electric screw is installed inside the sludge discharge trough, and a sliding baffle is slidably connected to the upper inner side of the sludge discharge trough. Side toothed rails are fixedly connected to both sides of the upper part of the sedimentation tank body. This utility model has a V-shaped tank bottom and a sludge discharge trough. With the electric screw and sliding baffle, during sedimentation, the sliding baffle can block most of the sludge, preventing the sludge from directly contacting the electric screw and avoiding sludge directly clogging the screw blades. During cleaning, the sliding baffle can be gradually pulled out to control the amount of sludge falling, which can significantly reduce the starting pressure of the electric screw and enhance the practicality of the device.

The invention discloses a coal bed gas pump-free gas lift lifting system and process, and relates to the technical field of coal bed gas drainage and mining. The coal bed gas pump-free gas lift lifting system comprises a drainage and mining pipe which is installed in a gas well through a sleeve; the multiple mixing devices are arranged in the drainage and mining pipe at intervals; the separation assembly is communicated with the drainage and mining pipe; the manifold equipment is communicated with the separation assembly through a pipeline and is at least provided with a collection port and a backflow port, the collection port is used for collecting the coal bed gas separated by the separation assembly, and the backflow port is used for enabling the coal bed gas to flow back; an inlet of the compressor is communicated with the reflux inlet, and an outlet of the compressor is communicated with the gas well; and the separation assembly adopts multi-stage separation to form an efficient separation effect, so that the coal bed gas flowing back to the compressor is ensured to be clean and dry, and the compressor is effectively prevented from being damaged by liquid impact and corrosion.