An adaptive suction system and control method thereof

Abstract

The present invention discloses an adaptive suction system and a control method thereof, comprising a delivery pump and a self-priming pump driven by a corresponding power device, wherein the water inlet of the delivery pump is connected to a water source through a suction pipe, the middle of the suction pipe between the water source and the water inlet is connected to an automatic exhauster with a liquid level sensor, the water outlet of the delivery pump is connected to the liquid outlet through a water outlet pipe, a check valve and a flow sensor; the water outlet pipeline from the water outlet to one side of the check valve branches out a self-priming pipeline, and the self-priming pipeline is connected to the water outlet pipeline on the other side of the check valve through a first electric control valve, a self-priming pump and a second electric control valve; the signal output ends of the liquid level sensor and the flow sensor are connected to the corresponding signal input ends of a PLC controller, and the corresponding control output ends of the PLC controller are respectively connected to the automatic exhauster, the first electric control valve, the second electric control valve and the controlled end of the power device. The present invention solves the industry problem of difficult liquid suction and delivery under complex and harsh conditions, while reducing the labor intensity of operators and improving work efficiency and safety.

Description

Technical Field

[0001] The invention relates to an automatic suction system, in particular to an adaptive suction system and a control method thereof, belonging to the technical field of fluid mechanical engineering. Background Art

[0002] In the fields of industry, agriculture, exploration, firefighting, etc., we often encounter working conditions such as firefighting seawater extraction and transportation, mine drainage, etc. These working conditions have the same characteristics of long distance, long suction range, deep liquid surface, etc., and the liquid source conditions are unstable and prone to interruption.

[0003] Since the existing multi-stage pumps used for long-distance transportation have poor self-priming ability and cannot independently complete self-priming operations, it is generally necessary to adopt manual pipeline pre-emptying measures, that is, use other equipment to pre-fill the suction pipeline with sufficient liquid before the operation, so that the liquid fills the suction pipeline, and then start the multi-stage pump to start transportation. This operation method has a large workload, high labor intensity, and a long time. In addition, simple perfusion often cannot form a stable liquid flow in the pipeline, and the self-priming success rate cannot be guaranteed after starting the multi-stage pump. Once the self-priming fails after startup, or the transportation is interrupted due to certain factors during the operation, the liquid in the pipeline will flow back and be emptied due to gravity. Continuing the operation requires repeated perfusion of liquid to empty the pipeline, which is very inconvenient. Summary of the invention

[0004] The purpose of the present invention is to provide an adaptive suction system with automatic pipeline exhaust, suction and transportation functions in response to the problems existing in the above-mentioned prior art, and at the same time provide an adaptive suction control method, so as to properly solve the industry problem of difficult liquid suction and transportation under complex and harsh conditions such as long suction range, deep liquid level and unstable working conditions.

[0005] In order to achieve the above objectives, the basic technical scheme of the adaptive suction system of the present invention is that it includes a delivery pump and a self-priming pump driven by corresponding power devices, the water inlet of the delivery pump is connected to a water source through a suction pipe, the middle of the suction pipe between the water source and the water inlet is connected to an automatic exhauster with a liquid level sensor, the water outlet of the delivery pump is connected to the liquid outlet through a water outlet pipe, a check valve and a flow sensor; the water outlet pipeline from the water outlet to one side of the check valve branches out into a self-priming pipeline, and the self-priming pipeline is connected to the water outlet pipeline on the other side of the check valve through a first electric control valve, a self-priming pump and a second electric control valve; the signal output ends of the liquid level sensor and the flow sensor are connected to the corresponding signal input ends of the PLC controller, and the corresponding control output ends of the PLC controller are respectively connected to the automatic exhauster, the first electric control valve, the second electric control valve and the controlled end of the power device.

[0006] The PLC controller implements adaptive suction control in the following steps:

[0007] Step 1: Exhaust - Receive the low liquid level signal sent by the liquid level sensor, start the automatic exhauster to exhaust the air in the suction pipe, until the liquid level sensor sends a full liquid signal, and close the automatic exhauster;

[0008] Step 2: Self-priming - Open the first and second electric control valves, start the self-priming pump, and stop the self-priming pump until the flow sensor transmits a stable predetermined flow signal;

[0009] The third step is transportation: close the first and second electric control valves, start the transportation pump, and start the transportation operation.

[0010] It can be seen that the working process of the present invention includes three stages: exhaust, self-priming and conveying. In the exhaust stage, the automatic exhauster is controlled to extract the air in the liquid suction pipeline; in the self-priming stage, the self-priming pump and the electric control valve are controlled to complete the liquid suction during exhaust and form a stable liquid flow; in the conveying stage, the conveying pump is controlled to perform the liquid conveying function. Since the present invention enables the conveying pump pipeline conveying system to have the functions of automatic exhaust, suction and conveying at the same time, it solves the industry problem of difficult liquid suction and conveying under complex and harsh conditions such as long suction range, deep liquid level and unstable working conditions, and at the same time reduces the labor intensity of operators and improves work efficiency and safety.

[0011] A further improvement of the present invention is that the power source drives the self-priming pump and the delivery pump respectively through the first transmission shaft and the second transmission shaft of the dual-output speed increasing box.

[0012] A further improvement of the present invention is that the speed increasing box includes a clutch having a neutral gear, a self-priming pump gear, and a delivery pump gear; when in the neutral gear, the first transmission shaft and the second transmission shaft are separated from the power source; when in the self-priming pump gear, the first transmission shaft is connected to the power source and the second transmission shaft is separated from the power source; when in the delivery pump gear, the second transmission shaft is connected to the power source and the first transmission shaft is separated from the power source.

[0013] A further improvement of the present invention is that the middle part of the suction pipe between the water source and the water inlet of the delivery pump is connected to an automatic air exhauster with a liquid level sensor through a liquid level tank.

[0014] A further improvement of the present invention is that an observation window is installed in the pipeline between the check valve and the flow sensor.

[0015] A further improvement of the present invention is that the delivery pump is a multistage pump or a centrifugal pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a piping system of an embodiment of the present invention, wherein the thin solid line is the self-priming system pipeline, the thick solid line is the delivery system pipeline, and the dotted line is the control system line.

[0017] Figure 2 for Figure 1 Schematic diagram of the pipeline connection structure of the embodiment.

[0018] Figure 3 for Figure 1 Electrical schematic diagram of adaptive control of an embodiment.

[0019] Figure 4 for Figure 1 Adaptive control flow chart of an embodiment.

[0020] In the figure: 101-power source 102-speed increasing box 103-first transmission shaft 104-second transmission shaft; 201-liquid level tank 202-automatic exhauster 203-liquid level sensor; 301-first electric control valve 302-self-priming pump 303-second electric control valve; 401-liquid inlet 402-multistage pump 403-check valve 404-observation window 405-flow sensor 406-liquid outlet; 501-PLC controller. DETAILED DESCRIPTION

[0021] Embodiment 1

[0022] The adaptive suction system of this embodiment has the functions of pipeline automation, suction, and transportation, and is used for water diversion operations in a salt field sea salt evaporation pool. Figure 1 and Figure 2 As shown, it is equipped with a multi-stage pump 402 (DY155-67×3 from Hunan Xiangdian Chang Pump Changyi Pump Co., Ltd.) and a self-priming pump 302 (SUB50-15 / 60 vane pump from Zhejiang Deli Equipment Co., Ltd.) purchased as a delivery pump. The two pumps are driven by the power source 101 through the first transmission shaft 103 and the second transmission shaft 104 of the double-output speed increaser 102. The speed increaser 102 includes a clutch with a neutral gear, a self-priming pump gear, and a multi-stage pump gear; when in the neutral gear, the first transmission shaft 103 and the second transmission shaft 104 are separated from the power source; when in the self-priming pump gear, the first transmission shaft 103 is connected to the power source, and the second transmission shaft 104 is separated from the power source; when in the multi-stage pump gear, the second transmission shaft 104 is connected to the power source, and the first transmission shaft 103 is separated from the power source. The water inlet of the multi-stage pump 402 is connected to a group of liquid inlets 401 of the water source through a suction pipe. The middle part of the suction pipe between the water source and the water inlet is connected to an automatic exhauster 202 (EJ1201, Shanghai Qi Yu Mechanical and Electrical Equipment Co., Ltd.) with a liquid level sensor 203 through a liquid level tank 201.

[0023] The water outlet of the multistage pump 402 is connected to a group of parallel liquid outlets 406 through the water outlet pipe, the check valve 403, the observation window 404 and the flow sensor 405. The water outlet pipeline from the water outlet of the multistage pump 402 to one side of the check valve 403 branches out into a self-priming pipeline, and the self-priming pipeline is connected to the water outlet pipeline on the other side of the check valve 403 through the first electric control valve 301, the self-priming pump 302 and the second electric control valve 303. The check valve 403 can prevent the liquid in the delivery pipeline from flowing back, so as to avoid the internal circulation when the self-priming pump 302 is working, and the liquid in the pipeline is refluxed and emptied due to the liquid outlet 406 being connected to the atmosphere after shutdown; the observation window 404 is used for operators to observe the liquid delivery status; the flow sensor 405 uses an electronic liquid turbine flowmeter, which can transmit the delivery flow signal to the PLC controller 501 to determine whether the self-priming is completed and monitor the delivery instantaneous flow and cumulative flow.

[0024] The signal output ends of the liquid level sensor 203 and the flow sensor 405 are connected to the corresponding signal input ends of the PLC controller 501, and the corresponding control output ends of the PLC controller 501 are respectively connected to the automatic exhauster 202, the first electrically controlled valve 301, the second electrically controlled valve 303 and the controlled ends of the power device (including the power source 101 and the speed increaser 102).

[0025] The specific control circuit used in this embodiment can be found in Figure 3 , you can use Figure 4 The PLC controller adaptive control process shown realizes "one-button automatic operation" and automatically monitors and controls during the operation to ensure continuous and safe liquid transportation:

[0026] 1. Exhaust operation stage

[0027] Before the system is started for the first time, the pipes and suction lines are filled with air. After the system is started, the liquid level sensor 203 detects that the liquid level in the suction pipe near the inlet of the multistage pump 402 is low or there is no liquid. The PLC controller 501 issues a command, and the system automatically enters the exhaust operation stage. At this time, the PLC controller 501 sends a control signal to turn on the automatic exhauster 202 and start to exhaust the air in the suction pipe until the liquid level sensor 203 detects that the suction pipe is full of liquid, that is, the liquid level reaches the vicinity of the inlet of the multistage pump 402, and transmits the liquid level signal to the PLC controller 501, and the PLC controller 501 determines that the exhaust stage is completed.

[0028] 2. Self-priming operation stage

[0029] After the exhaust operation stage is completed, the PLC controller 501 issues an instruction, and the system automatically enters the self-priming operation stage. At this time, the PLC controller 501 sends a control signal to close the automatic exhauster 202, open the first electric control valve 301 and the second electric control valve 303, and start the self-priming pump to enter the self-priming operation stage in combination with the self-priming pump gear of the speed increaser 102. The liquid flows through the suction pipeline to the liquid inlet 401, the multi-stage pump 402, the first electric control valve 301, the self-priming pump 302, the second electric control valve 303 to the observation window 404, the flow sensor 405, and then flows out from the liquid outlet 406 until the flow sensor 405 detects a stable flow signal and transmits the stable flow signal to the PLC controller 501. The PLC controller 501 determines that the self-priming stage is completed.

[0030] 3. Transportation operation stage

[0031] After the self-priming stage is completed, the PLC controller 501 issues a command, and the system automatically enters the conveying operation stage. At this time, the PLC controller 501 sends a control signal to the speed increaser 102 to separate the self-priming pump gear and combine the multi-stage pump gear, and at the same time close the first electric control valve 301 and the second electric control valve 303, and start the multi-stage pump 402 to enter the conveying operation stage. The liquid flows out from the liquid outlet 406 after passing through the suction pipeline to the liquid inlet 401, the multi-stage pump 402, the check valve 403, the observation window 404, and the flow sensor 405, and performs a stable conveying operation under the real-time monitoring of the PLC controller 501.

[0032] 4. System disconnection

[0033] During the conveying operation, if the pipeline system is interrupted due to a drastic change in the liquid source, the liquid level in the suction pipe will decrease and the infusion cannot be continued normally. The flow sensor 405 will send an abnormal flow signal, and the liquid level sensor 203 will detect that the liquid level in the suction pipe near the inlet of the multi-stage pump 402 is low or there is no liquid. At this time, the PLC controller 501 will send an audible and visual prompt signal, and at the same time send a control signal to separate the multi-stage pump gear of the speed increaser 102, and the automatic exhauster 202 will start, re-execute the exhaust stage operation, and start to exhaust the air in the suction pipe to prevent the multi-stage pump 402 from being damaged by idling for a long time.

[0034] 5. Job Pause / Complete

[0035] When the operation is completed or paused, the system is stopped. At this time, the first electrically controlled valve 301 and the second electrically controlled valve 302 are both in a closed state. Due to the action of the check valve 403, the suction pipe is in a sealed state and is not connected to the atmosphere. The liquid filled in the suction pipe will not flow back, thereby reducing or saving the exhaust operation time or process when starting the operation next time.

[0036] After adopting this embodiment, the industry problem of difficult liquid suction and delivery under complex and harsh conditions such as long suction range, deep liquid level, unstable working conditions, etc. is solved; the process of manual repeated filling pipeline exhaust operation can be omitted, greatly reducing the labor intensity of operators. Tests have shown that the self-priming success rate can be guaranteed, and the liquid backflow in the pipeline can be prevented when the system is shut down, thereby reducing repeated exhaust operations and improving work efficiency; and fully automatic monitoring and control of the operation process is realized, preventing the multi-stage pump from being damaged by long-term idling due to flow interruption, thereby improving the degree of automation and operation safety.

[0037] In addition to the above embodiments, the present invention may also have other implementations. For example, when in use, it may also be integrated and placed on a movable base such as a car chassis, a trailer chassis, a container-type shelter, etc.; its suction medium may also be different types such as oil and water; its multi-stage pump system may also be equivalently transformed into other corresponding centrifugal pumps, etc. All technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope required by the present invention.

Claims

1. A control method for an adaptive suction system, the system comprising a delivery pump and a self-priming pump driven by corresponding power devices, the water inlet of the delivery pump being connected to a water source through a suction pipe, the middle of the suction pipe between the water source and the water inlet being connected to an automatic exhauster with a liquid level sensor, the water outlet of the delivery pump being connected to a liquid outlet through a water outlet pipe, a check valve and a flow sensor; characterized in that: The water outlet pipeline from the water outlet to one side of the check valve branches out into a self-priming pipeline, and the self-priming pipeline is connected to the water outlet pipeline on the other side of the check valve through the first electric control valve, the self-priming pump and the second electric control valve; the signal output ends of the liquid level sensor and the flow sensor are connected to the corresponding signal input ends of the PLC controller, and the corresponding control output ends of the PLC controller are respectively connected to the automatic exhauster, the first electric control valve, the second electric control valve and the controlled end of the power device; The PLC controller implements adaptive suction control according to the following steps: Step 1: Exhaust - Receive the low liquid level signal sent by the liquid level sensor, start the automatic exhauster to exhaust the air in the suction pipe, until the liquid level sensor sends a full liquid signal, and close the automatic exhauster; Step 2: Self-priming - Open the first and second electric control valves, start the self-priming pump, and stop the self-priming pump until the flow sensor transmits a stable predetermined flow signal; The third step is transportation: close the first and second electric control valves, start the transportation pump, and start the transportation operation.

2. The control method of the adaptive suction system according to claim 1, characterized in that: The power device drives the self-priming pump and the delivery pump respectively through the first transmission shaft and the second transmission shaft of the dual-output speed increasing box.

3. The control method of the adaptive suction system according to claim 2, characterized in that: The speed increaser includes a clutch having a neutral gear, a self-priming pump gear, and a delivery pump gear; when in the neutral gear, the first transmission shaft and the second transmission shaft are separated from the power device; when in the self-priming pump gear, the first transmission shaft is connected to the power device and the second transmission shaft is separated from the power device; when in the delivery pump gear, the second transmission shaft is connected to the power device and the first transmission shaft is separated from the power device.

4. The control method of the adaptive suction system according to claim 3, characterized in that: The middle part of the suction pipe between the water source and the water inlet of the delivery pump is connected to an automatic air exhauster with a liquid level sensor through a liquid level tank.

5. The control method of the adaptive suction system according to claim 4, characterized in that: An observation window is arranged in the pipeline between the check valve and the flow sensor.

6. The control method of the adaptive suction system according to claim 5, characterized in that: The delivery pump is a multistage pump or a centrifugal pump.

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