Tube sampler capable of realizing under-pressure sampling, isothermal sampling and anti-shear sampling, and sampling method

[0035] Example one

[0036] The first embodiment provides a tubular sampler for realizing isothermal and shear-resistant sampling under pressure, which can directly sample under pressure, isothermal sampling, and shear-resistant sampling without affecting the normal transportation process of the crude oil pipeline 8, and No external force driving is required when sampling, the structure is simple, and the seal is reliable.

[0037] Such as figure 1 As shown, the tubular sampler includes a bypass pipeline 4 arranged obliquely with respect to the horizontal line. Preferably, the inlet end of the bypass pipeline 4 is set higher than the outlet end; the two ends of the bypass pipeline 4 are respectively connected to the bottom of the crude oil pipeline 8 Openable and closable communication, so as to realize sampling under pressure from the crude oil pipeline 8. The bypass pipeline 4 is used to continuously draw and seal the oil from the crude oil pipeline 8, and use the oil to continuously flow into the bypass pipeline 4 to achieve preheating The purpose of the (cold) sampler is to achieve isothermal sampling. No manual operation is required during the process of preheating the (cold) bypass pipeline 4 to reduce the sampling workload; when the gas is introduced into the bypass pipeline 4, the sealed oil The liquid flows out of the bypass pipeline 4 by its own gravity, and the height difference between the two ends of the bypass pipeline 4 allows the low-viscosity crude oil to flow out of the lowest end of the bypass pipeline 4 by gravity without any internal or external drive components. The structure is simple. Reliable sealing.

[0038] Preferably, a pressure gauge 3 is provided on the bypass pipeline 4, so that during the sampling operation, the pressure gauge 3 can timely monitor the oil pressure in the bypass pipeline 4 to ensure that the oil in the bypass pipeline 4 When the pressure is equal to the oil pressure of the oil in the crude oil pipeline 8, seal the oil in the bypass line 4; in addition, it can ensure that the oil in the bypass line 4 is sealed when the sealed oil is depressurized. The pressure of the liquid is relieved to atmospheric pressure, that is, the pressure gauge 3 shows 0MP, so as to ensure that the full pressure relief of the sealed oil is monitored, and to prevent the sealed oil from being affected by insufficient pressure relief when sampling from the bypass pipe 4 to the outside. Shearing effect.

[0039] Preferably, a thermometer 5 is provided on the bypass pipeline 4, and the thermometer 5 is used to monitor the temperature change of the oil in the bypass pipeline 4 during the sampling operation to ensure that the temperature of the oil in the bypass pipeline 4 and the crude oil pipeline 8 When the temperature of the oil is equal, the oil in the bypass pipe 4 is sealed; in addition, the thermometer 5 can also be used to monitor the preheating (cold) effect.

[0040] In order to facilitate the connection and fixation, an inlet section and an outlet section are vertically arranged at the inlet end and outlet end of the bypass pipeline 4, respectively. The inlet section and the outlet section are respectively connected to the crude oil pipeline 8, and the bypass pipeline 4 is arranged obliquely in the crude oil pipeline. 8 is connected to the bottom of the inlet section and the outlet section, so that the bypass pipeline 4 is connected in parallel between the upstream and downstream sides of the crude oil pipeline 8; the inlet section and the outlet section are respectively provided with an inlet control valve 1 and The outlet control valve 7 is used to control the on and off of the inlet end and the outlet end of the bypass pipeline 4 respectively; preferably, the inlet control valve 1 and the outlet control valve 7 are respectively set close to the crude oil pipeline 8 so that after the valve is closed, the The amount of oil between the valve and the crude oil pipeline 8 is as small as possible to ensure that when the oil is sealed, the amount of stagnant “dead oil” staying in the inlet section and the outlet section near the crude oil pipeline 8 is effectively reduced.

[0041] Preferably, the bypass pipeline 4 is provided with a drain inlet valve 2 and a sampling valve 6 respectively. The drain inlet valve 2 and the sampling valve 6 are respectively arranged at the inlet and outlet ends of the bypass pipeline 4, and the drain inlet The valve 2 is used to introduce the gas into the bypass pipe 4, and it is further preferred to connect the drain inlet valve 2 horizontally to the inlet section, and is located between the inlet control valve 1 and the inclined section, so that it can be exhausted before sampling During the process, the gas in the bypass pipe 4 can be discharged through the drain inlet valve 2 more quickly and efficiently; the sampling valve 6 is used to relieve the pressure of the oil contained in the bypass pipe 4 and flow out, and the sampling valve 6 is connected At the lowest end of the bypass line 4 to ensure that all the oil enclosed in the bypass line 4 can flow out of the sampling valve 6 by its own gravity, and the discharge and intake valve 2 is set higher than the sampling valve 6 , To ensure that after the oil enters the bypass pipe 4 in the reverse direction, the front end pushes the gas to be discharged through the drain inlet valve; in order to prevent the oil from stagnating in the sampling valve 6, it is further preferred to connect the sampling valve 6 vertically to the bypass pipe 4 is the bottom of the lowest end, and the outlet of the sampling valve 6 is vertically downward, so that the oil can flow out smoothly under the action of gravity.

[0042] It should be noted that the bypass pipeline 4 of the sampler preferably connects the inlet section to the upstream side of the crude oil pipeline 8, and connects the outlet section to the downstream side of the crude oil pipeline 8, so that the oil is in the bypass pipeline 4 during sampling. The flow direction inside is consistent with the flow direction of the crude oil pipeline 8, and when exhausting, it can be ensured that the inlet section is disconnected from the crude oil pipeline 8, so that the oil in the crude oil pipeline 8 is reversely introduced into the bypass pipeline 4, and then the bypass The gas in the connecting pipe 4 is discharged through the drain inlet valve 2; preferably, the various pipes of the sampler are welded to ensure the sealing performance and connection reliability of the pipe.

[0043] It is preferable that the maximum working pressure of the sampler is 6MPa and the maximum working temperature is 70℃. The pipe diameters of the bypass pipe 4, the inlet section and the outlet section are all DN32. The pipe length of the bypass pipe 4 is 65cm. The sampler can hold oil samples at a time. 500mL, the inlet section of the bypass pipeline 4 is provided with an intake and exhaust pipe, and the discharge intake valve 2 is installed on the intake and exhaust pipes. The diameter of the intake and exhaust pipes is DN15.

[0044] The working principle of the tubular sampler of the first embodiment is: using the bypass pipeline connected in parallel at the bottom of the crude oil pipeline 8 to control the inlet control valve 1 and the outlet control valve 7, so that the crude oil continues to flow through the bypass pipeline 4 to make the bypass The oil temperature in the connecting pipe 4 is the same as the oil temperature in the crude oil pipeline 8, and the temperature change is monitored by the thermometer 5 to achieve the purpose of isothermal sampling; during the sampling process, the pressure relief operation is performed by controlling the sampling valve 6 and the pressure gauge 3 is used to monitor whether Fully relieve the pressure to prevent the oil sample from being sheared; use the height difference between the two ends of the inclined bypass pipe 4 to let the low-viscosity crude oil flow out of the sampling valve 6 by gravity, and finally realize the pressure isothermal anti-shear sampling .

[0045] Example two

[0046] Based on the tubular sampler described in the first embodiment, the second embodiment proposes a sampling method for sampling directly from the crude oil pipeline 8 under pressure, isothermal and anti-shear, without affecting the normal transportation of the crude oil pipeline 8 The process does not require additional internal and external driving devices, with simple structure and reliable sealing.

[0047] The sampling method includes the following steps:

[0048] S1. Put the tube sampler in the initial state. The initial state needs to ensure that the inlet control valve 1, the outlet control valve 7, the drain inlet valve 2 and the sampling valve 6 are all in the closed state.

[0049] S2. Connect one end of the bypass pipe 4 of the tubular sampler with the crude oil pipe 8, and disconnect the other end from the crude oil pipe 8, introduce the oil in the crude oil pipe 8 into the bypass pipe 4 in one direction, and take the bypass pipe The gas in line 4 is exhausted.

[0050] Specifically, the outlet control valve 7 is opened first, and the drain inlet valve 2 is opened at the same time to ensure that the opening of the drain inlet valve 2 is small, and the oil in the crude oil pipeline 8 enters the bypass pipeline 4 through the outlet section in reverse. When inside, the air in the bypass pipeline 4 is drained through the drain inlet valve 2.

[0051] S3. After exhausting the gas, connect both ends of the bypass pipe 4 with the crude oil pipe 8 so that the oil in the crude oil pipe 8 continues to flow into the bypass pipe 4 in the same direction until the oil temperature in the bypass pipe 4 is warm The oil pressure is equal to the oil temperature and oil pressure in the crude oil pipeline 8.

[0052] Specifically, after draining the air in the bypass pipeline 4, first close the discharge inlet valve 2 and open the inlet control valve 1 to allow the oil in the crude oil pipeline 8 to flow into the bypass pipeline 4 in a forward direction. After the oil in the pipeline 4 continues to flow for a period of time, observe the changes in the pressure gauge 3 and the thermometer 5 until the thermometer 5 shows the same temperature as the oil temperature in the crude oil pipeline 8.

[0053] S4. Disconnect both ends of the bypass pipeline 4 from the crude oil pipeline 8 by closing the inlet control valve 1 and the outlet control valve 7, so that the oil in the bypass pipeline 4 is sealed; specifically, first close the outlet control valve 7 , And then close the inlet control valve 1. At this time, the uncut oil is sealed in the bypass pipe 4.

[0054] S5. Depressurize the oil sealed in the bypass pipe 4; specifically, after the oil is sealed, first open the sampling valve 6 to relieve the pressure until the pressure gauge 3 indicates 0MPa (that is, in the bypass pipe 4) The oil pressure is relieved to atmospheric pressure) to ensure that the pressure in the bypass pipe 4 is fully relieved; after the pressure relief is completed, a small amount of waste oil generated during the pressure relief operation is poured into the waste oil drum.

[0055] S6. Introduce gas into the bypass pipe 4 so that the sealed oil flows out of the bypass pipe 4 by its own gravity.

[0056] Specifically, after fully depressurizing is completed, first open the drain and intake valve 2, connect the bypass pipe 4 with the atmosphere, and introduce the gas into the bypass pipe 4. At this time, the oil in the bypass pipe 4 depends on its own gravity. Function, it flows out from the sampling valve 6 by itself, and the outflow oil sample collected by the sampling bottle is the isothermal unsheared oil sample.

[0057] S7. After sampling, close the sampling valve 6 and the drain inlet valve 2 at the same time, so that the tube sampler can be reset to the initial state.

[0058] In summary, the tubular sampler and sampling method of this embodiment have the following beneficial effects:

[0059] 1. It can directly sample under pressure without affecting the normal transportation process of crude oil pipeline 8;

[0060] 2. Use the crude oil to continue to flow through the sampler to achieve the purpose of preheating (cold) the sampler, and use the thermometer 5 to monitor whether the temperature is the same to achieve isothermal sampling. No manual operation is required during the process of preheating (cold) the sampler. Reduce sampling workload;

[0061] 3. During the sampling process, the pressure relief operation can be implemented through the control of the sampling valve 6, and the pressure gauge 3 can monitor whether the pressure is fully relieved to prevent the oil sample from being sheared, thereby completing the anti-shear sampling, and the pressure relief process Less waste oil;

[0062] 4. Utilizing the height difference between the two ends of the bypass pipeline 4, the low-viscosity crude oil flows out of the sampling valve 6 by gravity without any internal or external driving parts. The structure is simple and the seal is reliable.