CN202483554U - Oil well produced-fluid optical fiber measuring system - Google Patents

Abstract

The utility model relates to an optical fiber metering system for oil well liquid production, which includes a laser transmitter, an optical coupler, a Venturi tube, an optical fiber probe, an optical fiber pressure sensor, an optical detection device, a signal processing device, a computer , the laser transmitter, optical coupler, optical detection device, and signal processing device are installed on the ground; the Venturi tube is set in the oil pipe, the fiber optic probe is installed in the Venturi tube, the optical coupler is connected to the fiber probe through an optical fiber, and the optical fiber pressure sensor is located in the At the end of the fiber optic probe, the optical coupler is also connected with the light detection device, the light detection device is connected with the signal processing device, and the signal processing device is connected with the computer. The utility model has high detection sensitivity, strong anti-electromagnetic interference ability, little influence by medium temperature, and fast response speed, and can dynamically measure the liquid production of a single oil well without affecting the production of oil and gas wells, and has strong practicability. High measurement accuracy.

Description

Optical fiber metering system for oil well production

Technical field:

The utility model relates to a metering device for measuring liquid production in oil wells, in particular to an optical fiber metering system for liquid production in oil wells.

Background technique:

Orifice plate gas measurement is a traditional gas measurement method. It uses a throttle orifice and a bellows differential pressure gauge to measure, and calculates the gas flow according to the pressure difference before and after the gas flows through the orifice plate. This metering device has a simple structure and is easy to install, but the measuring range is small, only 1:3, and the metering accuracy is affected by the processing and installation accuracy of the orifice plate. the

Gas Roots flowmeter is a volumetric flowmeter with high measurement accuracy, suitable for precise volume measurement, and widely used in trade and precision storage and transportation measurement management. However, the natural gas separated in oil well measurement contains more liquid droplets, which will affect the lubrication of the flowmeter's rotating mechanism, and prone to jamming and blocking accidents, so this type of flowmeter is generally not suitable for use.

At present, the oil field is in a period of high water cut, and it is very difficult to discharge liquid after metering of oil wells with low gas-liquid ratio. The error of the original single well metering method is getting bigger and bigger, which is not conducive to the fine management of oil wells.

Invention content:

The purpose of the utility model is to provide an optical fiber metering system for oil well production, which is used to solve the problem of large errors in the existing oil well production single well measurement method.

The technical solution adopted by the utility model to solve the technical problems is: the optical fiber metering system for oil well production includes a laser transmitter, an optical coupler, a venturi tube, an optical fiber probe, an optical fiber pressure sensor, an optical detection device, a signal processing device, The computer, laser transmitter, optical coupler, optical detection device, and signal processing device are installed on the ground; the Venturi tube is installed in the oil pipe, the optical fiber probe is installed in the Venturi tube, the optical coupler is connected to the optical fiber probe through the optical fiber, and the optical fiber pressure sensor Located at the end of the optical fiber probe, the optical coupler is also connected with the light detection device, the light detection device is connected with the signal processing device, and the signal processing device is connected with the computer.

The Wenturi tube in the above scheme is composed of an inlet and outlet cylindrical section, a conical contraction section, a cylindrical throat and a conical diffuser section. The diameter of the inlet cylindrical section is the same as the inner diameter of the oil pipe. There is a negative pressure hole.

In the above solution, the computer is connected to the printer, and the metering data can be printed out through the printer.

The utility model has the following beneficial effects:

1. The utility model has high detection sensitivity, strong anti-electromagnetic interference ability, little influence by medium temperature, and fast response speed. It can dynamically measure the liquid production of a single oil well without affecting the production of oil and gas wells, and has strong practicality. , high measurement accuracy.

2. The venturi tube of the utility model has a simple structure, no plug-ins, does not interfere with fluid flow, has small pressure loss, is less affected by changes in fluid properties, is easy to implement, safe and reliable, and is suitable for downhole flow measurement and control.

Description of drawings

Fig. 1 is a block diagram of the utility model;

Fig. 2 is a schematic structural view of the venturi tube of the present invention.

1. Inlet cylindrical section, 2. Conical contraction section, 3. Cylindrical throat, 4. Conical diffusion section, 5. Outlet cylindrical section 6 Pressure-taking holes 7 Negative pressure-taking holes.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described:

As shown in Figure 1, this optical fiber metering system for oil well production includes a laser transmitter, an optical coupler, a Venturi tube, an optical fiber probe, an optical fiber pressure sensor, an optical detection device, a signal processing device, a computer, a laser transmitter, an optical coupling The detector, optical detection device, and signal processing device are installed on the ground; the venturi tube is set in the oil pipe under the ground, the optical fiber probe is installed in the venturi tube, the optical coupler is connected to the optical fiber probe through a high-temperature optical fiber, and the optical fiber pressure sensor is located at the end of the optical fiber probe. The optical coupler is also connected to the light detection device, the light detection device is connected to the signal processing device, the signal processing device is connected to the computer, the computer is connected to the printer, and the light detection device is a laser detector. the

As shown in Figure 2, the Venturi tube consists of an inlet cylindrical section 1, a conical constriction section 2, a cylindrical throat 3, a conical diffuser section 4, and an outlet cylindrical section 5. The diameter of the inlet cylindrical section 1 is the same as the inner diameter of the tubing. There is a pressure-taking hole 6 on the section, and a negative pressure-taking hole 7 is opened in the cylindrical throat 3 . The Venturi tube uses the relationship between the differential pressure before and after the throttling device and the average flow velocity and flow rate, and calculates the flow rate based on the differential pressure measurement value. When the liquid in the pipeline flows through the Venturi tube, the liquid flow section shrinks, and the flow velocity increases at the contraction section. , the pressure decreases, so that a pressure difference is generated before and after the Venturi tube, and then the flow rate is calculated according to the measured pressure difference.

The laser transmitter is used to generate a high-power stable laser signal, which is sent to the optical coupler, and then sent to the high-temperature optical fiber from the ground to the downhole through the optical coupler. Inside the oil pipe, the wall of the oil pipe is used, and the throttling mode is designed in the middle to reduce the eddy current; the optical fiber pressure sensor is located at the end of the optical fiber, and the optical fiber is just a transmission line of light, which converts the measured physical quantity into the amplitude and phase of light Or the change of the amplitude, the measured data is transmitted to the ground through the optical fiber pressure sensor and optical fiber, and then the measured data is converted into the flow data of each phase through the optical detection device, signal processing device and computer.

Claims (3)

1. An optical fiber metering system for oil well production, characterized in that: this optical fiber metering system for oil well production includes a laser transmitter, an optical coupler, a Venturi tube, an optical fiber probe, an optical fiber pressure sensor, an optical detection device, and a signal processing device , computer, laser transmitter, optical coupler, optical detection device, and signal processing device are installed on the ground; the Venturi tube is set in the oil pipe, the optical fiber probe is installed in the Venturi tube, the optical coupler is connected to the optical fiber probe through the optical fiber, and the optical fiber pressure The sensor is located at the end of the optical fiber probe, the optical coupler is also connected with the light detection device, the light detection device is connected with the signal processing device, and the signal processing device is connected with the computer. 2. The optical fiber metering system for oil well liquid production according to claim 1, characterized in that: the Venturi tube is composed of a cylindrical section at the entrance and exit, a conical constriction section (2), a cylindrical throat (3) and a conical diffusion section (4) Composition, the diameter of the inlet cylindrical section (1) is the same as the inner diameter of the tubing, and there is a pressure-taking hole (6) on this section, and a negative-pressure pressure-taking hole (7) is opened on the cylindrical throat. 3. The optical fiber metering system for oil well fluid production according to claim 1, characterized in that the computer is connected to a printer.

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