Apparatus for testing rock drillability under stratum condition

Abstract

The invention discloses an apparatus for testing rock drillability under a stratum condition, which comprises a clamping mechanism, a pressure balancing mechanism and a power mechanism, wherein the clamping mechanism is arranged at the lower end of the pressure balancing mechanism; the power mechanism is arranged in the pressure balancing mechanism and the clamping mechanism; the clamping mechanism consists of a clamp holder kettle body, a taper sleeve, a rubber sleeve, an upper plunger and a lower plunger; the pressure balancing mechanism consists of a wellhole pressure kettle body, a bit pressure kettle body and a bit pressure piston; and the power mechanism consists of a motor, a speed reducer, a canine impacter and a drill stem. The testing apparatus, which adopts the structure of mechanical-electrical integration, can test the rock drillability really and accurately by simulating the temperature, confining pressure, pore pressure and wellhole slurry pressure under the stratum condition, particularly the overlying confining pressure, pore pressure and wellhole slurry pressure of over 90 MPa of strata, and therefore has a more practical instruction significance for well drilling construction.

Description

technical field [0001] The invention belongs to oil / natural gas exploitation equipment, in particular to a rock drillability tester under stratum conditions, which is an essential equipment for studying rock drillability by simulating stratum condition drilling in oil / gas exploitation engineering. Background technique [0002] In oil / gas drilling engineering, in order to choose a reasonable drill bit and drilling process, it is necessary to know the drillability of rock. Because the drillability of rock is not only related to the mechanical strength of the rock itself, but also closely related to the drilling technology, especially the rock temperature, in-situ stress state, mud drilling, gas drilling, over-balanced drilling or under-balanced drilling have a great influence on the drilling speed. It is very easy to cause the rock drillability grading measured indoors cannot be applied to field drilling. [0003] For this reason, many oil / gas drilling equipment companies are...

AI Technical Summary

Problems solved by technology

Although it is more realistic to test the dynamic physical characteristics of rock formations, there are dynamic seals connected inside and outside the kettle, and these seals are likely to cause seal failure, resulting in large measurement errors

[0004] About the testing device of rock drillability under formation conditions, relevant reports are also often seen in open publications, but there is no report identical with the present invention

Images