阅读说明：本技术 一种移动式井口的取样装置及方法 (Sampling device and method for movable wellhead ) 是由 柯玉彪 李华昌 陈曦 陈彦梅 骆仕洪 易枫 何静意 徐彬 庄园 徐硕 曾建军 于 2018-09-07 设计创作，主要内容包括：本发明涉及一种移动式井口的取样装置及方法,包括框体,所述框体内安装有第一上游控制球阀,所述转换接头上安装有就地压力表考克,所述上游控制球阀另一端通过三通管件连通有净化干燥管的一端,所述净化干燥管的另一端连接有一级调压阀,所述一级调压阀通过三通管件连通有二级调压阀,所述二级调压阀连接有三通管体,所述三通管体的上端连接第二上游控制球阀,下端连接溢流阀,所述第二上游控制球阀通过三通管件连接有第二上游截断阀,所述第二上游截断阀连接有取样瓶,所述取样瓶连接有下游截断阀,所述三通球阀、溢流阀和下游截断阀均通过软体管连接有碱液桶。通过两次降压使用气体压强达到所需值,达到泄压的目的,安全性高。(The invention relates to a sampling device and a method of a movable wellhead, which comprises a frame body, wherein a first upstream control ball valve is arranged in the frame body, the conversion joint is provided with a local pressure gauge cock, the other end of the upstream control ball valve is communicated with one end of a purifying and drying pipe through a three-way pipe, the other end of the purifying and drying pipe is connected with a primary pressure regulating valve which is communicated with a secondary pressure regulating valve through a three-way pipe fitting, the second-stage pressure regulating valve is connected with a three-way pipe body, the upper end of the three-way pipe body is connected with a second upstream control ball valve, the lower end of the three-way pipe body is connected with an overflow valve, the second upstream control ball valve is connected with a second upstream block valve through a three-way pipe fitting, the second upstream block valve is connected with a sampling bottle, the sampling bottle is connected with a downstream cut-off valve, and the three-way ball valve, the overflow valve and the downstream cut-off valve are all connected with an alkaline liquid barrel through soft pipes. The pressure of the gas is used to reach the required value through two times of depressurization, so that the purpose of pressure relief is achieved, and the safety is high.)

1. A sampling device of a mobile wellhead, comprising a frame (16), characterized in that: install first upper reaches control ball valve (4) in framework (16), the one end of first upper reaches control ball valve (4) is connected with crossover sub (2) through sample hose (3), crossover sub (2) set up outside framework (16), install manometer cock (1) on crossover sub (2) on the spot, the upper reaches control ball valve (4) other end has the one end of purifying and drying pipe (6) through tee pipe fitting (18) intercommunication, the other end of purifying and drying pipe (6) is connected with one-level air-vent valve (7), one-level air-vent valve (7) have second grade air-vent valve (8) through tee pipe fitting (18) intercommunication, second grade air-vent valve (8) are connected with tee pipe body (10), second upper reaches control ball valve (17) is connected to the upper end of tee pipe body (10), overflow valve (11) are connected to the lower extreme, second upper reaches control ball valve (17) are connected with second upper reaches through tee pipe fitting (18) and cut off valve (12) ) The second upstream cut-off valve (12) is connected with one end of a sampling bottle (13), the other end of the sampling bottle (13) is connected with a downstream cut-off valve (14), and the three-way ball valve (9), the overflow valve (11) and the downstream cut-off valve (14) are connected with an alkaline liquid barrel (15) through a hose.

2. A mobile wellhead sampling device as claimed in claim 1, in which: the in-situ pressure gauge cock (1) is 9/16' auclave (F).

3. A mobile wellhead sampling device as claimed in claim 1, in which: the type of the conversion joint (2) is 9/16auclave (M) -1/4' -NPT (M).

4. A mobile wellhead sampling device as claimed in claim 1, in which: the sampling hose (3) is a telescopic hose.

5. A mobile wellhead sampling device as claimed in claim 1, in which: and a pressure gauge (5) is arranged on the three-way pipe fitting (18).

6. A sampling method of a movable wellhead is characterized in that: the method comprises the following steps:

a, mounting: connecting the adapter with a sampling port at the wellhead, opening a first upstream control ball valve (4), and enabling gas in the well to flow into a purification drying pipe (6) under the pressure action in the well;

b, purifying and filtering: adjusting a purifying and drying pipe (6), observing the number of a pressure gauge (5), keeping the internal pressure of the pipe at 55-65Mpa, requiring 40um for drying precision, and removing impurities and water vapor in the gas.

c, decompressing: adjusting a first-stage pressure regulating valve (7) to enable the pressure at the input end to be 0-60Mpa, the pressure at the output end to be 0-15Mpa, the range requirement of a pressure gauge to be 25Mpa and the precision to be 1.6, enabling the pressure to be reduced to 15Mpa, adjusting a second-stage pressure regulating valve (8) to enable the precision to be 1.6, enabling the pressure at the input end to be 0-25Mpa, the pressure at the output end to be 0-1Mpa, the range requirement of a force gauge to be 3Mpa and the precision to be 1.0, enabling the pressure to be reduced to 1.5 Mpa;

d, overflow: after the pressure is reduced by the secondary pressure regulating valve (8), the pressure value is still higher than 1.5Mpa, the overflow valve (11) jumps, the gas is decompressed by the overflow valve (11), the acid gas is neutralized by the hose and flows into the alkaline solution barrel, and the overflow valve is closed and the decompression is stopped after the pressure is reduced to 1.5 Mpa;

e, sampling: after the pressure is reduced to 1.5Mpa of the pressure value of the sampling bottle (13), the second upstream block valve (12) is opened, and the gas after pressure reduction flows into the sampling bottle (13);

and f, gas replacement, wherein two lines are designed for gas, and one line is as follows: gas replacement is arranged between the sampling port and the decompressed three-way ball valve (9), and mainly replaces the purifying and drying pipe (6) and enters the alkaline liquid barrel (15) through the three-way ball valve (9); the other gas enters the sampling bottle (13), the gas in the sampling bottle (13) is sampling gas,

g, after the sample is accomplished, adjust tee bend ball valve (9) repeatedly, carry out the pressure release to residual pressure in the device, be zero to the manometer reading, dismantle well head crossover sub (2), install manometer on the well head on the spot, the sample is ended, removes the device, carries out next well head sample.

Technical Field

The invention belongs to the technical field of oil and gas development, and particularly relates to a sampling device and method for a movable wellhead.

Background

The gas production tree of the wellhead of the gas well of the oil and gas field usually comprises four layers of casings from bottom to top, a first technical casing, a second technical casing and an oil layer casing, the casings are all positioned in a square well pool, abnormal pressure rise phenomena of different degrees occur in all the casings at all levels, the pressure change condition needs to be monitored timely and effectively, the initial development stage of the meta-dam marine acid gas field is that the wellhead pressure is up to 30-40Mpa, the hydrogen sulfide content averagely reaches 5-8mol%, the gas well has the characteristics of high pressure and high sulfur content, the gas field development dynamic state is tracked, the fluid produced by the gas field needs to be sampled and analyzed periodically, and the sampling accuracy and safety of the gas field are challenged by the high-pressure and high-sulfur environment.

At present, the sampling device and the method for the high-pressure and high-sulfur gas field mainly comprise 2 types:

(1) through the two-stage throttling of the ground gathering flow, the pressure of a wellhead is reduced to 10-13Mpa, then the pressure is reduced to 1.5Mpa through a pressure reducing valve of a sampling box, and the sampling is completed by utilizing a fixed gas sampling device.

(2) After the secondary throttling of the ground gathering flow, the water vapor in the gas is separated through a gas-liquid separation device, the pressure is reduced to be below 5-7Mpa through the third throttling, then the pressure is reduced to be below 1.5Mpa through a pressure reducing valve of a sampling box, and the sampling is finished by utilizing a fixed gas sampling device.

The above sampling device and method are based on ground throttling, and are provided with a fixed sampling device, which mainly has the following problems:

(1) a ground gathering and transporting flow is built in a high-pressure and high-sulfur-content production well, throttling and pressure reduction can be carried out, but the long-stop abandoned well has no ground gathering and transporting flow and no fixed sampling device, the well opening shut-in oil pressure is up to 40-50Mpa, the high-pressure well opening can not be sampled at present, and a gas sampling bottle below 10Mpa can not meet the safety requirement under the high-pressure condition.

(2) The acid gas blowby phenomenon takes place for some well casing annular space, and well head casing shows unusual high pressure, high sulphur characteristics, and in the sample process, need carry out the pressure release to the casing annular space to below 10Mpa in advance. Because density difference, gas mainly distributes in the sleeve pipe on upper portion, and liquid mainly distributes in the lower part, because chemical reaction between gas and liquid in addition, there is the difference in different position gaseous phase or liquid phase component in the short time, often lets out upper portion gas earlier during the pressure release to can't in time obtain the accurate gas sample in top or liquid sample.

Disclosure of Invention

The invention aims to overcome the problems in the prior art, and provides a sampling device and a method for a movable wellhead, which can be used for long-stop abandoned wells and abnormal annular pressure-relief wells without ground gathering and transportation processes and fixed sampling devices, and are suitable for high-pressure and high-sulfur wellheads.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows.

The utility model provides a sampling device of portable well head, includes the framework, its characterized in that: the improved vacuum drying device is characterized in that a first upstream control ball valve is installed in the frame, one end of the first upstream control ball valve is connected with a conversion joint through a sampling hose, the conversion joint is arranged outside the frame, a local pressure gauge cock is installed on the conversion joint, the other end of the upstream control ball valve is communicated with one end of a purifying and drying pipe through a tee pipe fitting, the other end of the purifying and drying pipe is connected with a primary pressure regulating valve, the primary pressure regulating valve is communicated with a secondary pressure regulating valve through a tee pipe fitting, the secondary pressure regulating valve is connected with a tee pipe body, the upper end of the tee pipe body is connected with a second upstream control ball valve, the lower end of the tee pipe body is connected with an overflow valve, the second upstream control ball valve is connected with a second upstream block valve through a tee pipe fitting, the second upstream block valve is connected with one end, The overflow valve and the downstream block valve are both connected with an alkaline liquid barrel through a soft pipe.

The in-situ pressure gauge cock is model 9/16 "" auclave (F).

The model of the conversion joint is 9/16auclave (M) -1/4' -NPT (M).

The sampling hose is a telescopic hose.

And a pressure gauge is arranged on the three-way pipe fitting.

A sampling method of a movable wellhead is characterized in that: the method comprises the following steps:

a, mounting: connecting the adapter with a sampling port at the wellhead, opening a first upstream control ball valve, and allowing gas in the well to flow into a purification drying pipe under the pressure in the well;

b, purifying and filtering: adjusting the purifying and drying tube, observing the number of a pressure gauge to keep the internal pressure of the purifying and drying tube at 55-65Mpa, wherein the drying precision is required to be 40um, and removing impurities and water vapor in the gas.

c, decompressing: adjusting the primary pressure regulating valve to enable the pressure at the input end to be 0-60Mpa, the pressure at the output end to be 0-15Mpa, the range requirement of a pressure gauge to be 25Mpa and the precision to be 1.6, reducing the pressure to 15Mpa, adjusting the secondary pressure regulating valve to enable the precision to be 1.6, enabling the pressure at the input end to be 0-25Mpa, the pressure at the output end to be 0-1Mpa, the range requirement of a force gauge to be 3Mpa and the precision to be 1.0, reducing the pressure to 1.5Mpa, and completing pressure reduction;

d, overflow: after the pressure is reduced by the secondary pressure regulating valve, the pressure value is still higher than 1.5Mpa, the overflow valve jumps, the gas is decompressed by the overflow valve, the acid gas is neutralized by the hose and flows into the alkaline liquid barrel, and after the pressure is reduced to 1.5Mpa, the overflow valve is closed and the pressure is stopped;

e, sampling: after the pressure is reduced to 1.5Mpa, the second upstream block valve is opened, and the gas after pressure reduction flows into the sampling bottle;

and f, gas replacement, wherein two lines are designed for gas, and one line is as follows: gas replacement is arranged between the sampling port and the three-way ball valve after pressure reduction, mainly replaces a purifying drying pipe, and enters an alkaline liquid barrel through the three-way ball valve; the other gas enters the sampling bottle, the gas in the sampling bottle is sampling gas,

g, after the sample, adjust the tee bend ball valve repeatedly, carry out the pressure release to residual pressure in the device, be zero to the manometer reading, dismantle well head crossover sub, install manometer on the well head on the spot, the sample is ended, removes the device, carries out next well head sample.

The invention has the advantages.

1. The pressure is reduced to 15Mpa through the first-stage pressure regulating valve, then the pressure is reduced to 1.5Mpa by using the second-stage pressure regulating valve, the pressure of 1.5Mpa is kept, the requirement that gas enters a sampling bottle under the pressure of 1.5Mpa is met, the pressure is not high, the pressure is not low, the pressure requirement that the gas enters the sampling bottle is met, the sampling precision is ensured, and the wellhead high pressure and high sulfur content are realized aiming at a long-stop abandoned well and an abnormal annulus pressure starting well which have no ground gathering and transportation process and a fixed sampling device; the pressure is reduced without a pressure relief mode, the top gas sample is obtained in time, the problem of sampling accuracy check is solved, additional processes and sampling device installation are not needed, the fixed cost is saved, two persons cooperate to operate simultaneously, the operation intensity is reduced, and the working efficiency is improved; in the field of application: in the aspect of samples, the device is mainly used for taking gas samples, but is not limited to gas samples, the gas sample bottle is replaced by the liquid sample bottle, and the device can be used for taking gas field water samples by adjusting pressure. In the field, the sampling device can be applied to the sampling process of oil and gas field exploitation, can also be applied to sampling of petrochemical high-pressure and toxic gases, and can be further expanded to sampling of medical pharmaceutical high-pressure and toxic gases; the application prospect is as follows: the invention solves the technical problems of abnormal high pressure and high sulfur content of the well mouth and is difficult to sample, and the invention is mobile, simple and convenient to carry, convenient to operate, low in safety risk, high in sample accuracy and free from occupying too much manpower, material resources and time. Fixed cost of installing fixed sampling device in production well gas production well site with gathering and transportation flow is 70000 yuan, replacement spare and accessory parts and maintenance cost 10000 annually, if the device is adopted, each long stop abandoned well and annular abnormal start killing well can save cost 80000 yuan, only aiming at abnormal high pressure and high sulfur gas field of the meta dam, 20 abnormal start stop abandoned wells and annular abnormal start killing well exist, cost can be saved by 160 ten thousand yuan, and the device is applied to other abnormal start pressure and high sulfur gas field, even sampling of high pressure and toxic gas in petrochemical industry and medical pharmacy, and cost saving will be recorded by billion.

2. The accuracy is higher by the model 9/16' auclave (F) of the local pressure gauge cock.

3. By means of the model 9/16auclave (M) -1/4' -NPT (M) of the conversion joint, the sealing performance is good, and the stability is high.

4. The telescopic range of the hose is improved through the telescopic hose.

5. The pressure gauge is convenient for observing pressure data.

6. The required value is reached through two steps of pressure reduction using gas pressure, and the pressure that will not descend leaks through the overflow valve, because there is the possibility of factors such as human misoperation, leads to the air-vent valve decompression inefficacy, or the decompression is not in place, and the pressure still is higher than the 1.5Mpa that the sampling tube required after the second grade decompression, for the security of guarantee sampling operation process, reaches the purpose of pressure release, and the security is high.

Drawings

FIG. 1 is a schematic view of the structure of the present invention.

The labels in the figure are: 1. the device comprises an on-site pressure gauge cock, 2, a conversion joint, 3, a sampling hose, 4, a first upstream control ball valve, 5, a pressure gauge, 6, a purification drying pipe, 7, a primary pressure regulating valve, 8, a secondary pressure regulating valve, 9, a three-way ball valve, 10, a three-way pipe body, 11, an overflow valve, 12, a second upstream cut-off valve, 13, a sampling bottle, 14, a downstream cut-off valve, 15, an alkaline liquid barrel, 16, a frame body, 17, a second upstream control ball valve, 18 and a three-way pipe.

Detailed Description

The invention is further described below with reference to the accompanying drawings.