Oil well mouth sampling device, decompression device and sampling method

Abstract

The invention discloses an oil well mouth sampling device, a decompression device and a sampling method. The sampling device comprises a decompression device and a sampling bottle; an outlet of the decompression device is connected with an inlet of the sampling bottle, the device further comprises a uniflow valve and a uniflow valve opening and closing device, and the uniflow valve opening and closing device comprises an outer pipe, a screw, a nut and an ejector rod; the screw is located inside the outer pipe, the ejector rod is arranged at the front end of the screw, the ejector rod is connected with a valve ball of the uniflow valve, the uniflow valve is connected with a well opening ground flow pipeline, the screw is cooperatively connected with the nut, the nut is blocked at the rear end of the outer pipe, the front end of the outer pipe is connected with a valve body of the uniflow valve, a fluid outflow opening is formed in the outer pipe body, and the upper end of the decompression device is connected with the fluid outflow opening. The well mouth ground flow pipeline, the uniflow valve, the outer pipe, the decompression device and the sampling bottle are sequentially communicated. Obtained well mouth fluid samples can be more truly close to multi-phase fluid at the well bottom; meanwhile, the method enables the sampling operation process to be safer.

Description

technical field [0001] The invention relates to oil exploitation technology, in particular to an oil well head sampling device, a decompression device and a sampling method. Background technique [0002] The physical parameters of the formation fluid are very important parameters for evaluating the reserves of oil and gas reservoirs. This parameter is obtained by analyzing the formation fluid samples in the laboratory. Therefore, the quality of the samples directly determines whether the evaluation of the oil and gas reservoir is correct or not. At present, the wellhead sampling of oil wells mostly adopts the traditional in-line sampling method. In this method, a gate is installed on the process pipeline on the surface of the wellhead, and the in-line sampling is carried out into the sampling cylinder by controlling the gate, and the sampling cylinder is open. Since this sampling method is similar to the blowing type, it is easy to cause liquid or gas splashing during the sa...

AI Technical Summary

Problems solved by technology

Since this sampling method is similar to the blowing type, it is easy to cause liquid or gas splashing during the sampling process without the treatment of depressurization, cooling, and airtightness; not only the samples lose their authenticity and accuracy, but also the on-site operators will There will be hidden dangers in health, safety, environmental protection, etc.

Especially in steam huff and puff wells and steam flooding production wells, there are safety risks such as sampling and scalding in high temperature and high pressure environments

Images