A core sealing device applied to a hydraulic pressurized coring tool

Abstract

The invention discloses a rock core sealing device for a hydraulic pressurized type coring tool. The rock core sealing device comprises a safety joint, a release gear, an outer barrel assembly, an inner barrel assembly and a core catcher assembly, wherein the safety joint serves as a cone with hollow bottom and top and a larger upper part and a smaller lower part; the middle part of the safety joint is in threaded connection with the outer barrel assembly, and the lower part thereof is in threaded connection with the release device; the inner barrel assembly is arranged below the release device; the core catcher assembly is arranged below the inner barrel assembly; the release device, the inner barrel assembly and the core catcher assembly are positioned in the outer barrel assembly. The rock core sealing device for the hydraulic pressurized type coring tool disclosed by the invention can reasonably utilize the hydraulic pressure of the drilling fluid to completely encapsulate the crushed core; when the core catcher assembly is plastically deformed to certain degree, the drilling fluid is discharged from a gap between a rock core seal cartridge and an adapter sleeve, so that the rock core is not over-compressed, and the integrity of the rock core is ensured. Finally, the purpose that the rock core seal cartridge completely encapsulates the crushed core can be achieved; furthermore, the coring yield rate on a soft and broken stratum can be ensured.

Description

technical field [0001] The invention belongs to the field of drilling and coring, and in particular relates to a rock core sealing device applied to a hydraulic pressurized coring tool. Background technique [0002] In the coring operation of soft and broken formations, there are mainly the following problems: the low strength of formation cement makes it difficult for the core to form and it is difficult to enter the coring tool. When the core cement has strong water sensitivity, the bearing capacity of the core is reduced under the erosion of water-based drilling fluid, and it is easy to collapse and break, resulting in core plugging and core grinding, thereby affecting the core technical indicators. During the coring process of loosely cemented and heterogeneous pebble-containing glutenite, the vibration of the core drill bit and tools can easily cause the core to break and break. During the core extraction process, due to changes in the stress state of the core column, ...

AI Technical Summary

Problems solved by technology

Coring tools used in coring operations for soft and broken strata in the prior art are still relatively backward, and the average coring yield is extremely low, and accidents such as core pumping or core drop are prone to occur during use

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