A deep water surface conduit device

Abstract

The invention discloses a deepwater surface riser device. The deepwater surface riser device comprises a conical outer barrel, a conical inner barrel, a circular wellhead and a disc cover plate; the lower orifice of the conical outer barrel is smaller in diameter than that of the upper orifice of the conical inner barrel; the upper orifice of the conical outer barrel is provided in a sealed mode with the disc cover plate; the disc cover plate is provided with a through hole; the circular wellhead is vertically fixed onto the disc cover plate; the conical inner barrel is arranged inside a circular cavity formed between the conical outer barrel and the circular wellhead and can slide up and down along the circular wellhead; when the conical inner barrel slides close to the lower orifice of the conical outer barrel, the conical outer barrel and the conical inner barrel are matched with each other through a fastening structure. The deepwater surface riser device integrates an offshore suction anchor mounting technique, a deepwater surface jet drilling technique and a common casing pipe drilling technique into a whole and gives full play to the advantages of the three techniques duringdeepwater surface drilling.

Description

technical field [0001] The invention relates to a deep-water surface conduit device, which belongs to the technical field of deep-water drilling equipment and operations. Background technique [0002] The existing deep-water surface conduit is a circular pipe with an outer diameter of 36in or 30in and a single length of about 12m, which is connected into a conduit string through a threaded joint, and installed on the deep-water seabed by drilling, spraying, or underwater hammering. , as a support structure for underwater wellheads. The drilling method is used to install the conduit. First, the drill string is lowered for subsea drilling to form a wellbore for the surface conduit to run into. After the drill string is pulled out, the connected conduit string is lowered into the drilled wellbore, and cement is injected into the drill string into the conduit in the conduit string tube and returned to the annulus between the conduit and the open hole to complete the cementing o...

AI Technical Summary

Problems solved by technology

The pipe is installed too shallow into the mud, and the support force for the wellhead is not enough, which is prone to wellhead sinking accidents

The design of the conduit is too deep into the mud, the installation time is long, and it is easy to be installed incorrectly during the implementation process. Complex deep-water underwater operations such as underwater cutting are required, and the operation time is low and the operation cost is high.

In addition, for the drilling method of drilling the wellbore first and then running the conduit to install the conduit, it is easy to find the wellbore in the process of running the conduit, and the efficiency of the cementing operation is low, and the cementing quality is not easy to guarantee

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