Double-pipeline flow balance control method

Abstract

The invention discloses a double-pipeline flow balance control method which is specifically implemented according to the following steps: step 1, detecting flows on two pipelines, and transmitting detected flow information to a control system; 2, the control system calculates the difference value of the flows of the two pipelines; and 3, adjusting the opening degrees of the adjusting valves on the two pipelines according to the difference value obtained in the step 2. The situation that the given value of the adjusting valve changes greatly when the liquid feeding amount fluctuates greatly is avoided, the flow difference value of the two pipelines is basically kept within a small numerical range, namely, the given value of the electric adjusting valve is basically kept within the small numerical range, the flow adjusting stability is good, and the process production process runs stably.

Description

Technical Field

[0001] The invention belongs to the technical field of petrochemical equipment, and in particular relates to a dual-pipeline flow balance control method. Background Art

[0002] Flow balancing is widely used in the surface engineering production process of oil and gas fields. It is mainly used to adjust and control the medium flow of pipelines from a certain upper-level process equipment to multiple process equipment at the next level, so that the flow of each branch pipeline remains basically the same.

[0003] For dual-pipeline flow control, each pipeline is installed with an electric regulating valve and flow meter, where the electric regulating valve is used to control the size of the flow. If the flow meter shows that the flow on the pipeline is larger or smaller, the flow on the pipeline will be controlled by the electric regulating valve on the pipeline to ensure that the flow on the two pipelines remains consistent. This control method has a good flow regulation and balancing effect on the stable oil flow process, but when the incoming liquid volume fluctuates greatly, the adjustment set value of the electric regulating valve changes greatly, and the regulating valve needs a large stroke action to adjust the opening. The adjustment time of the two pipeline flows tending to the same set value is long, the adjustment lag is large, and the flow deviation of the two branch pipelines is large during the adjustment process. At the same time, in the case of large flow changes, there is a flow that exceeds the adjustable range of the regulating valve, and the electric regulating valve cannot adjust the flow of the two pipelines, resulting in the inability to achieve stable flow balance in the two branch pipelines. Summary of the invention

[0004] The purpose of the present invention is to provide a dual-pipeline flow balance control method to solve the problem that when the existing pipeline flow control method is used to adjust the liquid volume fluctuation, the regulating valve needs a large stroke action to adjust the opening, the adjustment time of the two pipeline flows tending to the same set value is long, the adjustment hysteresis is large, and the flow deviation of the two branch pipelines is large during the adjustment process.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: a dual-pipeline flow balance control method, which is specifically implemented according to the following steps:

[0006] Step 1, detecting the flow rates on the two pipelines and transmitting the detected flow information to the control system;

[0007] Step 2, the control system calculates the difference in flow rates on the two pipelines;

[0008] Step 3, adjusting the openings of the regulating valves on the two pipelines according to the difference obtained in step 2.

[0009] As a preferred technical solution of the present invention, in step 1, a flow meter is arranged on each of the two pipelines to detect the flow rate.

[0010] As a preferred technical solution of the present invention, in step 1: a first flow meter and a first regulating valve are provided on the first pipeline; and a second flow meter and a second regulating valve are provided on the second pipeline.

[0011] As a preferred technical solution of the present invention, in step 3, if the difference between the first flow meter and the second flow meter is greater than 0, the control system is adjusted to reduce the opening of the first regulating valve and increase the opening of the second regulating valve.

[0012] As a preferred technical solution of the present invention, in step 3, if the difference between the first flow meter and the second flow meter is less than 0, the control system is adjusted to increase the opening of the first regulating valve and decrease the opening of the second regulating valve.

[0013] As a preferred technical solution of the present invention, in step 3, if the difference between the first flow meter and the second flow meter is 0, no adjustment is performed.

[0014] As a preferred technical solution of the present invention, both the first regulating valve and the second regulating valve are electric regulating valves.

[0015] The beneficial effects of the present invention are as follows: the dual-pipeline flow balance control method of the present invention adopts the flow difference between two pipelines as the adjustment parameter of the electric control valves on the two pipelines. When the flow of the two pipelines changes and there is a flow difference, the control system calculates the flow difference between the two sets of flow meters, and uses the flow difference as the given value of the control valve to adjust the flow. When the incoming liquid volume fluctuates greatly, this method does not have a situation where the given value of the control valve changes greatly. The flow difference between the two pipelines is basically maintained within a small numerical range, that is, the given value of the electric control valve is basically maintained within a small numerical range, the flow regulation stability is better, and the process production flow runs smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the existing dual-pipeline flow balance control method;

[0017] Figure 2 It is a principle diagram of the dual-pipeline flow balance control method of the present invention.

[0018] In the figure: 1. first flow meter, 2. first regulating valve, 3. control system, 4. second flow meter, 5. second regulating valve. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with the accompanying drawings, tables and specific embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0020] The present invention is further described below by way of examples, but is not limited to the following embodiments.

[0021] Example 1

[0022] like Figure 1 As shown in the figure, taking the oil transportation process of a station as an example, the oil from the well site passes through the 1# and 2# oil collecting and ball dosing devices respectively, and the crude oil is combined and enters the tank type scaling device, and is divided into two routes after passing through the tank type scaling device and enters the 1# and 2# oil and gas distribution and integrated integrated devices respectively. The 1# flow meter and 1# electric regulating valve are respectively set at the inlet pipeline of the 1# oil and gas distribution and integrated integrated device, and the 2# flow meter and 2# electric regulating valve are respectively set at the inlet pipeline of the 2# oil and gas distribution and integrated integrated device. The crude oil is separated and pressurized by the oil and gas distribution and integrated integrated device and then metered and transported to the downstream station. The station control system performs logic programming, and uses the flow parameter of the flow meter after the electric control valve as the given value of the electric control valve to adjust the valve opening. When the inlet flow of the 1# oil and gas distribution integrated device increases, the 1# electric control valve reduces the opening of the control valve to reduce the flow to the set value range, otherwise, the control valve opening is increased to increase the flow to the set value range; when the inlet flow of the 2# oil and gas distribution integrated device increases, the 2# electric control valve reduces the opening of the control valve to reduce the flow to the set value range, otherwise, the control valve opening is increased to increase the flow to the set value range. Through the regulation and control of the 1# and 2# electric control valves, the inlet pipeline flow of the two sets of oil and gas distribution integrated devices is basically consistent or within a certain set value range. This control method has a good flow regulation and balancing effect on the stable oil flow process, but when the incoming liquid volume fluctuates greatly, the regulation given value of the electric control valve changes greatly, and the control valve needs a large stroke action to adjust the opening. The adjustment time of the two pipeline flows tending to the same set value is long, the adjustment hysteresis is large, and the flow deviation of the two branch pipelines is large during the adjustment process. At the same time, when the flow changes greatly, there is a flow that exceeds the adjustable range of the control valve, and the electric control valve cannot adjust the flow of the two pipelines, resulting in the two branch pipelines being unable to achieve stable flow balance.

[0023] like Figure 2 As shown, the dual-pipeline flow balance control method of the present invention is implemented in the following steps:

[0024] Step 1: a first flow meter and a first regulating valve are provided on the first pipeline; a second flow meter and a second regulating valve are provided on the second pipeline; and flow information detected by the first flow meter and the second flow meter is transmitted to the control system;

[0025] Step 2, the control system calculates the difference in flow rates on the two pipelines;

[0026] Step 3, adjusting the openings of the regulating valves on the two pipelines according to the difference obtained in step 2.

[0027] The dual-pipeline flow balance control method of the present invention adopts the flow difference between two pipelines as the adjustment parameter of the regulating valves on the two pipelines. When the flow of the two pipelines changes and there is a flow difference, the control system calculates the flow difference of the two sets of flow meters and uses the flow difference as the given value of the regulating valve to adjust the flow.

[0028] In this method, when the incoming liquid volume fluctuates greatly, there is no situation where the given value of the regulating valve changes greatly. The flow difference between the two pipelines is basically maintained in a small numerical range, that is, the given value of the regulating valve is basically maintained in a small numerical range, the flow regulation stability is good, and the process production process runs smoothly.

[0029] Example 2

[0030] like Figure 2 As shown, different from Example 1, in the dual-pipeline flow balance control method of the present invention, the openings of the regulating valves on the two pipelines are adjusted according to the difference obtained in step 2, and one of the situations is that the flow difference between the two pipelines is not 0.

[0031] If the difference between the first flow meter and the second flow meter is greater than 0, the control system is adjusted to reduce the opening of the first regulating valve and increase the opening of the second regulating valve;

[0032] If the difference between the first flow meter and the second flow meter is less than 0, the control system is adjusted to increase the opening of the first regulating valve and reduce the opening of the second regulating valve.

[0033] By adjusting the first flow meter and the second flow meter respectively, balanced adjustment of the flow rates of the two pipelines can be quickly completed at a smaller opening.

[0034] Example 3

[0035] like Figure 2 As shown, different from Example 1, in the dual-pipeline flow balance control method of the present invention, in the dual-pipeline flow balance control method of the present invention, the openings of the regulating valves on the two pipelines are adjusted according to the difference obtained in step 2, one of which is:

[0036] If the difference between the first flow meter and the second flow meter is 0, no adjustment is performed. This is the situation when the two pipelines are working normally.

[0037] Example 4

[0038] like Figure 2 As shown, different from Example 1, in the dual-pipeline flow balance control method of the present invention, the first regulating valve and the second regulating valve are both electric regulating valves, which facilitates the control system to operate the first regulating valve and the second regulating valve.

[0039] The above description shows and describes several preferred embodiments of the invention, but as mentioned above, it should be understood that the invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall be within the scope of protection of the claims attached to the invention without departing from the spirit and scope of the invention.

Claims

1. A dual-pipeline flow balance control method, characterized in that: Follow the steps below to implement it: Step 1, detecting the flow rates on the two pipelines and transmitting the detected flow information to the control system; Step 2, the control system calculates the difference in flow rates on the two pipelines; Step 3, adjusting the openings of the regulating valves on the two pipelines according to the difference obtained in step 2.

2. The dual-pipeline flow balance control method according to claim 1, characterized in that: In step 1, a flow meter is arranged on each of the two pipelines to detect the flow rate.

3. The dual-pipeline flow balance control method according to claim 2, characterized in that: In step 1: a first flow meter and a first regulating valve are arranged on the first pipeline; a second flow meter and a second regulating valve are arranged on the second pipeline.

4. The dual-pipeline flow balance control method according to claim 3, characterized in that: In step 3, if the difference between the first flow meter and the second flow meter is greater than 0, the opening of the first regulating valve is reduced and the opening of the second regulating valve is increased through the control system.

5. The dual-pipeline flow balance control method according to claim 4, characterized in that: In step 3, if the difference between the first flow meter and the second flow meter is less than 0, the control system is used to increase the opening of the first regulating valve and decrease the opening of the second regulating valve.

6. The dual-pipeline flow balance control method according to claim 5, characterized in that: In step 3, if the difference between the first flow meter and the second flow meter is 0, no adjustment is performed.

7. The dual-pipeline flow balance control method according to claim 6, characterized in that: The first regulating valve and the second regulating valve are both electric regulating valves.

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