Deep-sea sediment core pressure-maintaining device matched with submarine drilling rig and method for using deep-sea sediment core pressure-maintaining device

Abstract

The invention discloses a deep-sea sediment core pressure-maintaining device matched with a submarine drilling rig and a method for using the deep-sea sediment core pressure-maintaining device. The deep-sea sediment core pressure-maintaining device comprises an upper seal cover, a metal hollow drilling rod, a sampling tube and a lower seal cover, wherein the sampling tube is arranged in the metal hollow drilling rod; the metal hollow drilling rod is connected with the upper seal cover and the lower seal cover by fine threads; the upper seal cover and the lower seal cover respectively comprise an inflation valve, a top cover, a pressure shell, an expandable air cushion and O rings; the top cover and the expandable air cushion are arranged in the pressure shell; the O rings are arranged between the pressure shell and the top cover and between the pressure shell and the expandable air cushion; and the inflation valve is arranged on the top cover. The deep-sea sediment core pressure-maintaining device is matched with the submarine drilling rig, can maintain in-situ pressure in the process of extracting deep-sea sediments from a sea bed to a sea surface, and can guarantee non-loss of hydrocarbon gas such as methane gas and non-melting of a hydrate. The invention is applied to drilling and coring ocean sediments by using the submarine drilling rig and can be widely applied to exploration of ocean resources such as the hydrate and deep-sea oil and gas resources.

Description

technical field [0001] The invention relates to a deep-sea sediment core pressure-holding device matched with a seabed drilling rig and an application method thereof. Background technique [0002] Drilling cores for seabed resources is the ultimate means of marine geological exploration and the only means of obtaining geological reserves. Drilling and coring is also one of the important means of marine engineering geological survey. Drilling the seabed with ocean drill ships is currently the main method for ocean resource exploration, but this method is not economical enough. Offshore drilling ships have large tonnage and high consumption. For the investigation of seabed hydrate resources and marine engineering geological survey, the drilling depth is generally tens of meters to 200 meters. The development trend of this type of drilling is to use general-purpose scientific research ships to carry underwater drilling rigs that can operate autonomously on the seabed. In ord...

AI Technical Summary

Problems solved by technology

The structure of the previous pressure-holding technology is too complicated and its own weight is heavy, while the scientific research ship as the mother ship of the underwater drilling rig is usually small in tonnage, and the deck space and the load-bearing capacity of the crane are very limited

Existing pressure-holding technology is not suitable for pressure-holding of underwater drilling rig cores

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