Multi-material accurate conveying system with multi-stage pumps connected in series

Abstract

The invention discloses a multi-material precise conveying system with multiple stages of pumps connected in series, which belongs to the technical field of material flow control and comprises at least two material feeding pipelines connected with a stirring reaction kettle. A corresponding material storage tank is arranged on each material feeding pipeline, and a metering pump and a pressure isolation pump are sequentially arranged on the material pipeline between the material storage tank and the stirring reaction kettle; a first pressure transmitter is arranged on the material pipeline between the metering pump and the pressure isolation pump and is used for detecting the pipeline pressure between the metering pump and the pressure isolation pump; the metering pump, the pressure isolation pump and the first pressure transmitter are electrically connected with the electrical control device; the electrical control device is used for controlling the rotating speed of a motor of the pressure isolation pump, so that the pipeline pressure at the outlet end of the metering pump is stable. Accurate conveying of multiple materials can be achieved according to the set proportion, and the precision and stability of material conveying are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of material flow control, and in particular relates to a multi-material precision conveying system with multi-stage pumps connected in series. Background Art

[0002] When multiple materials are automatically mixed and reacted, it is necessary to use a metering pump to transport multiple component materials to the stirring back pressure kettle for mixing and stirring at a constant flow rate according to the proportion. When using a metering pump, under the condition of the same material viscosity and rotation speed, the change in pressure will affect the volumetric efficiency of the metering pump, thereby directly affecting the output flow.

[0003] When conveying multi-component materials, the existing metering pumps will have different input and output pressures due to the different flow rates and pipe diameters of the various components, resulting in large fluctuations in material conveying errors. In addition, during the mixing and stirring of multiple materials and gases in the stirring back pressure kettle, the materials will undergo chemical reactions, causing changes in material properties, and bringing about changes in temperature and pressure, thereby causing changes in the pressure at the outlet of the metering pump. The volumetric efficiency of the metering pump at the same speed will be affected by changes in the pump outlet pressure, so when the stirring back pressure kettle undergoes a continuous mixing reaction, it will affect the output flow of the metering pump. Summary of the invention

[0004] In response to one or more of the above defects or improvement needs in the prior art, the present invention provides a multi-material precision conveying system with multi-stage pumps connected in series, so that precise conveying of multiple materials can be achieved according to a set ratio, thereby improving the accuracy and stability of material conveying.

[0005] To achieve the above-mentioned object, the present invention provides a multi-material precision conveying system with multi-stage pumps in series, comprising at least two material feed pipelines connected to a stirred reactor; Each material feed pipeline is provided with a corresponding material storage tank, and a metering pump and a pressure isolation pump are provided in sequence on the material pipeline between the material storage tank and the stirred reactor; a first pressure transmitter is provided on the material pipeline between the metering pump and the pressure isolation pump for detecting the pipeline pressure between the two; The metering pump, the pressure isolation pump, and the first pressure transmitter are all electrically connected to the electrical control device; the electrical control device is used to control the motor speed of the pressure isolation pump, thereby stabilizing the pipeline pressure at the outlet end of the metering pump.

[0006] As a further improvement of the present invention, a delivery pump is further provided on the material pipeline between the material storage tank and the metering pump, and a second pressure transmitter is provided on the material pipeline between the delivery pump and the metering pump for detecting the pipeline pressure between the two; The delivery pump and the second pressure transmitter are both electrically connected to the electrical control device, and the electrical control device is used to control the motor speed of the delivery pump, so as to stabilize the pipeline pressure at the inlet end of the metering pump.

[0007] As a further improvement of the present invention, the metering pump operates at a constant speed; or, A flow meter is provided on the material pipeline between the metering pump and the pressure isolation pump. The flow meter is electrically connected to the electrical control device, and the motor speed of the metering pump is controlled by the electrical control device.

[0008] As a further improvement of the present invention, a filtering device is further provided on the material pipeline between the delivery pump and the metering pump.

[0009] As a further improvement of the present invention, a first ball valve is provided on the material pipeline between the material storage tank and the delivery pump.

[0010] As a further improvement of the present invention, a second ball valve is provided on the material pipeline between the pressure isolation pump and the stirred reactor, and a branch pipe is provided between the pressure isolation pump and the second ball valve, and a third ball valve is provided on the branch pipe.

[0011] As a further improvement of the present invention, a stirring shaft is provided inside the material storage tank, and / or the tank wall of the material storage tank is a jacket structure.

[0012] As a further improvement of the present invention, the delivery pump, metering pump and pressure isolation pump are all gear metering pumps, screw pumps or peristaltic pumps; and / or, The flow meter is a mass flow meter, an ultrasonic flow meter or an electromagnetic flow meter; and / or, The electrical control device adopts a PLC controller or a PID controller.

[0013] As a further improvement of the present invention, a plurality of pressure isolation pumps are arranged between the metering pump and the stirred reactor, and a corresponding pressure transmitter is arranged between two adjacent pressure isolation pumps, and the pressure isolation pump and the pressure transmitter are both connected to the electrical control device.

[0014] As a further improvement of the present invention, the material is a liquid or a solid-liquid mixture.

[0015] In general, the above technical solution conceived by the present invention has the following beneficial effects compared with the prior art: (1) The multi-stage pump series multi-material precision conveying system of the present invention can be used for multi-channel materials in parallel, and the materials are conveyed to the stirred reactor through the corresponding material feed pipeline. The first pressure transmitter is connected to the electrical control device to adjust the motor speed of the pressure isolation pump to achieve stable pipeline pressure at the outlet of the metering pump. Therefore, the flow change of the metering pump will not be disturbed by the pressure change generated during the conveying of multi-component materials, so that the precise conveying of multiple materials can be achieved according to the set ratio, which improves the accuracy and stability of material conveying.

[0016] (2) The multi-material precision conveying system of the present invention, which has a multi-stage pump in series, controls the pipeline pressure at the outlet of the metering pump to be stable by the first pressure transmitter. At the same time, a conveying pump is provided on the material pipeline between the material storage tank and the metering pump, and a second pressure transmitter is provided on the material pipeline between the conveying pump and the metering pump. The second pressure transmitter is connected to an electrical control device to adjust the motor speed of the conveying pump, thereby achieving stable pipeline pressure at the inlet of the metering pump. The system is suitable for materials with high viscosity and poor fluidity.

[0017] (3) The multi-material precision conveying system of the present invention with multi-stage pumps in series overcomes the problem of large fluctuations in material conveying errors caused by different input and output pressures due to different flow rates and pipe diameters of the component materials when conveying multi-component materials.

[0018] (4) In the multi-material precision conveying system of the present invention, the metering pump is operated at a constant speed or controlled by a flow meter to operate at a set flow rate. When the pressure of the pipelines before and after the metering pump is stable, the flow rate of the metering pump can be further ensured to be stable.

[0019] (5) The multi-material precision conveying system with multi-stage pumps connected in series of the present invention can be equipped with multiple pressure isolation pumps between the metering pump and the stirred reactor, and corresponding pressure transmitters are provided between two adjacent pressure isolation pumps. The pressure transmitters are all connected to the electrical control device to control the motor speed of the corresponding pressure isolation pump respectively, so that the material pipeline pressure between the metering pump and the stirred reactor can be controlled in stages. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of a multi-material precision conveying system in which multi-stage pumps are connected in series according to an embodiment of the present invention.

[0021] In all the drawings, the same figure marks represent the same technical features, specifically: 1. material storage tank; 2. first ball valve; 3. material pipeline; 4. filtering device; 5. metering pump; 6. flow meter; 7. first pressure transmitter; 8. pressure isolation pump; 9. transfer pump; 10. second pressure transmitter; 11. stirred reactor; 12. discharge port; 13. electrical control device; 14. second ball valve; 15. third ball valve; 16. second material feed pipeline; 17. Nth material feed pipeline. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0027] like Figure 1 As shown, in one embodiment of the present invention, a multi-material precision conveying system with a multi-stage pump in series includes at least two material feed pipelines connected to a stirred reactor 11, which are used to input at least two materials from the corresponding material feed pipelines into the stirred reactor 11 according to a set ratio. The material can be a liquid or a solid-liquid mixture, and the multi-component material is output through its discharge port 12 after being stirred and reacted in the stirred reactor 11. A corresponding material storage tank 1 is provided on each material feed pipeline, and a metering pump 5 and a pressure isolation pump 8 are provided on the material pipeline 3 between the material storage tank 1 and the stirred reactor 11 in sequence, and a first pressure transmitter 7 is provided between the metering pump 5 and the pressure isolation pump 8 for detecting the pipeline pressure between the two.

[0028] The metering pump 5, the pressure isolation pump 8, and the first pressure transmitter 7 are all electrically connected to the electrical control device 13. The electrical control device 13 is used to control the motor speed of the pressure isolation pump 8 according to the pressure value fed back by the first pressure transmitter 7, so as to stabilize the pipeline pressure at the outlet of the metering pump 5, so that the flow change of the metering pump 5 will not be disturbed by the pressure change generated during the transportation of multi-component materials, and prevent the pressure change from interfering with the accuracy of the metering pump 5, so as to achieve accurate transportation of multiple materials according to the set ratio.

[0029] In the above embodiment, for materials with lower viscosity, only the metering pump 5 and the pressure isolation pump 8 are provided, and a first pressure transmitter 7 is provided between the two to stabilize the outlet pressure of the metering pump 5. However, for materials with higher viscosity, the fluidity is poor, and the metering pump 5 not only needs to play a metering role, but also needs to provide power for the materials with higher viscosity to be sucked into the pump, which will affect the stability of the metering pump 5. Therefore, in another embodiment of the present invention, a delivery pump 9 is further provided on the material pipeline between the material storage tank 1 and the metering pump 5, and a second pressure transmitter 10 is provided on the material pipeline between the delivery pump 9 and the metering pump 5, and the delivery pump 9 provides power for pumping in the material, and the electrical control device 13 is connected through the second pressure transmitter 10 to adjust the motor speed of the delivery pump 9, thereby stabilizing the inlet pressure of the metering pump 5.

[0030] That is, in this embodiment, if Figure 1As shown, each material feed pipeline is provided with a corresponding material storage tank 1, and a delivery pump 9, a metering pump 5, and a pressure isolation pump 8 are provided in sequence on the material pipeline 3 between the material storage tank 1 and the stirred reactor 11. A first pressure transmitter 7 is provided between the metering pump 5 and the pressure isolation pump 8 for detecting the pipeline pressure between the two; a second pressure transmitter 10 is provided between the delivery pump 9 and the metering pump 5 for detecting the pipeline pressure between the two. The delivery pump 9, the metering pump 5, the pressure isolation pump 8, the first pressure transmitter 7, and the second pressure transmitter 10 are all electrically connected to the electrical control device 13, and the electrical control device 13 is used to control the motor speed of the pressure isolation pump 8 according to the pressure value fed back by the first pressure transmitter 7, and at the same time control the motor speed of the delivery pump 9 according to the pressure value fed back by the second pressure transmitter 10.

[0031] In this embodiment, the delivery pump 9 delivers the material output from the material storage tank 1 to the inlet end of the metering pump 5 through the second pressure transmitter 10. Since the delivery pump 9 and the second pressure transmitter 10 of this embodiment are both connected to the electrical control device 13, the signal of the second pressure transmitter 10 is connected to the electrical control device 13, and the electrical control device 13 can receive the pressure value fed back by the second pressure transmitter 10 and compare it with the set pressure value, and adjust the motor speed of the delivery pump 9 according to the pressure value, so as to stabilize the pipeline pressure at the inlet end of the metering pump 5.

[0032] Furthermore, in this embodiment, the pressure isolation pump 8 can transport the material from the outlet of the metering pump 5 to the inlet of the stirred reactor 11 after passing through the first pressure transmitter 7. Since the pressure isolation pump 8 and the first pressure transmitter 7 of this embodiment are both connected to the electrical control device 13, the signal of the first pressure transmitter 7 is connected to the electrical control device 13, and the electrical control device 13 can receive the pressure value fed back by the first pressure transmitter 7 and compare it with the set pressure value, and adjust the motor speed of the pressure isolation pump 8 according to the pressure value, so as to stabilize the pressure at the outlet of the metering pump 5.

[0033] In the multi-material precision conveying system with multi-stage pumps connected in series in this embodiment, the pipeline pressure at the inlet end of the metering pump 5 is stably controlled by the conveying pump 9, and the pipeline pressure at the outlet end of the metering pump 5 is stably controlled by the pressure isolation pump 8, so that the flow change of the metering pump 5 will not be disturbed by the pressure change generated during the transportation of multi-component materials, preventing the pressure change from interfering with the accuracy of the metering pump 5, thereby realizing the precise delivery of multiple materials according to the set ratio.

[0034] It should be noted that in this application, the signal transmission and data processing between the electrical control device 13 and the pressure transmitter (including the first pressure transmitter 7 and the second pressure transmitter 10), the delivery pump 9, and the pressure isolation pump 8 can all adopt the existing technology, and this application does not involve the improvement of the algorithm. For example, it can be understood by those skilled in the art that the data processing of this embodiment only involves a simple threshold comparison. If the measured pressure value is too large compared with the set pressure value, the motor speed is increased, or if the measured pressure value is too small compared with the set pressure value, the motor speed is reduced.

[0035] Preferably, the metering pump 5 runs at a constant speed under the control of the electrical control device 13; or, a flow meter 6 is further provided on the material pipeline between the metering pump 5 and the pressure isolation pump 8, and the flow meter 6 is electrically connected to the electrical control device 13, and the signal of the flow meter 6 is connected to the electrical control device 13 to adjust the motor speed of the metering pump 5 through the electrical control device 13, and control the metering pump 5 to run according to the set flow rate, so that the material flow output to the flow meter 6 is stable. Based on the above design, when the pressure of the pipelines before and after the metering pump 5 is stable, the flow rate of the metering pump 5 can be further ensured to be stable.

[0036] Preferably, a filtering device 4 is further provided on the material pipeline between the delivery pump 9 and the metering pump 5 , for filtering the material outputted from the material storage tank 1 to prevent impurities from affecting the accuracy of the metering pump 5 .

[0037] Preferably, a first ball valve 2 is provided on the material pipeline between the material storage tank 1 and the delivery pump 9, and the first ball valve 2 is used to control the opening and closing of the material storage tank 1 discharge. Preferably, a second ball valve 14 is provided on the material pipeline between the pressure isolation pump 8 and the stirred reactor 11, and a branch pipe is also provided between the pressure isolation pump 8 and the second ball valve 14, and a third ball valve 15 is provided on the branch pipe. Through the cooperation of the second ball valve 14 and the third ball valve 15, the delivery device can be calibrated before use. Specifically, since the weight or volume of the material output within the set flow rate and the set time is constant, the second ball valve 14 is closed and the third ball valve 15 is opened during calibration, and the weight or volume of the material output from the branch pipe within the set flow rate and the set time is measured to achieve calibration. After the calibration is completed, the third ball valve 15 is closed and the second ball valve 14 is opened to achieve the switching of the pipeline, and the material pipeline is connected to the stirred reactor 11.

[0038] Preferably, the delivery pump 9, the metering pump 5, and the pressure isolation pump 8 are conventional gear metering pumps, screw pumps, or peristaltic pumps; the flow meter 6 is a mass flow meter, an ultrasonic flow meter, or an electromagnetic flow meter; and the electrical control device 13 is a PLC controller or a PID controller.

[0039] Preferably, the material storage tank 1 has stirring and jacketing functions, that is, a stirring shaft is provided inside the material storage tank 1 to ensure the uniformity of the material; the tank wall of the material storage tank 1 is a jacket structure to control the material temperature and avoid volume changes caused by temperature changes interfering with the flow control of the gear metering pump (volumetric metering pump).

[0040] Figure 1 Only the structure of the first material feed pipeline is shown. For the second material feed pipeline 16 to the Nth material feed pipeline 17 connected in parallel with the first material feed pipeline on the stirred reactor 11, the above design can be referred to and will not be repeated here. The material feed pipelines run in parallel.

[0041] In addition, in the present embodiment, a pressure isolation pump 8 is arranged between the metering pump 5 and the stirred reactor 11. In other embodiments, multiple pressure isolation pumps 8 can also be arranged between the metering pump 5 and the stirred reactor 11, and corresponding pressure transmitters are arranged between two adjacent pressure isolation pumps 8. Each pressure isolation pump 8 and pressure transmitter is connected to the electrical control device 13 to respectively control the motor speed of the corresponding pressure isolation pump 8, so that the material pipeline pressure between the metering pump 5 and the stirred reactor 11 can be graded and controlled.

[0042] The multi-material precision conveying system with multi-stage pumps in series in this embodiment was used to carry out a continuous liquid material metering and conveying test (in the test, the conveying pump 9, the metering pump 5, and the pressure isolation pump 8 all adopted conventional gear metering pumps, and the flowmeter 6 adopted an ultrasonic flowmeter). The results showed that the metering error of the material conveying of this system was ±0.2g / min. Therefore, the conveying system of this embodiment can achieve precise material conveying.

[0043] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-material precision conveying system with multi-stage pumps in series, characterized in that: It comprises at least two material feed pipelines connected to the stirred reactor (11); Each material feed pipeline is provided with a corresponding material storage tank (1), and a metering pump (5) and a pressure isolation pump (8) are provided in sequence on the material pipeline between the material storage tank (1) and the stirred reactor (11); a first pressure transmitter (7) is provided on the material pipeline between the metering pump (5) and the pressure isolation pump (8) for detecting the pipeline pressure between the two; The metering pump (5), the pressure isolation pump (8), and the first pressure transmitter (7) are all electrically connected to an electrical control device (13); the electrical control device (13) is used to control the motor speed of the pressure isolation pump (8), thereby stabilizing the pipeline pressure at the outlet end of the metering pump (5).

2. The multi-material precision conveying system of multi-stage pumps connected in series according to claim 1 is characterized in that: A delivery pump (9) is also provided on the material pipeline between the material storage tank (1) and the metering pump (5), and a second pressure transmitter (10) is provided on the material pipeline between the delivery pump (9) and the metering pump (5) for detecting the pipeline pressure between the two; The delivery pump (9) and the second pressure transmitter (10) are both electrically connected to an electrical control device (13), and the electrical control device (13) is used to control the motor speed of the delivery pump (9), thereby stabilizing the pipeline pressure at the inlet end of the metering pump (5).

3. The multi-material precision conveying system with multi-stage pumps in series according to claim 1 or 2, characterized in that: The metering pump (5) operates at a constant speed; or, A flow meter (6) is provided on the material pipeline between the metering pump (5) and the pressure isolation pump (8); the flow meter (6) is electrically connected to an electrical control device (13), and the electrical control device (13) controls the motor speed of the metering pump (5).

4. The multi-material precision conveying system with multi-stage pumps in series according to claim 2 is characterized in that: A filtering device (4) is also provided on the material pipeline between the delivery pump (9) and the metering pump (5).

5. The multi-material precision conveying system with multi-stage pumps in series according to claim 2 is characterized in that: A first ball valve (2) is provided on the material pipeline between the material storage tank (1) and the delivery pump (9).

6. The multi-material precision conveying system with multi-stage pumps in series according to claim 1 or 2, characterized in that: A second ball valve (14) is provided on the material pipeline between the pressure isolation pump (8) and the stirred reactor (11), and a branch pipe is provided between the pressure isolation pump (8) and the second ball valve (14), and a third ball valve (15) is provided on the branch pipe.

7. The multi-material precision conveying system with multi-stage pumps in series according to claim 1 or 2, characterized in that: The material storage tank (1) is provided with a stirring shaft inside, and / or the tank wall of the material storage tank (1) is a jacket structure.

8. The multi-material precision conveying system with multi-stage pumps in series according to claim 2 is characterized in that: The delivery pump (9), metering pump (5), and pressure isolation pump (8) are all gear metering pumps, screw pumps, or peristaltic pumps; and / or, The flow meter (6) is a mass flow meter, an ultrasonic flow meter or an electromagnetic flow meter; and / or, The electrical control device (13) adopts a PLC controller or a PID controller.

9. The multi-material precision conveying system with multi-stage pumps in series according to claim 1 or 2, characterized in that: A plurality of pressure isolation pumps (8) are arranged between the metering pump (5) and the stirred reactor (11), and a corresponding pressure transmitter is arranged between two adjacent pressure isolation pumps (8), and the pressure isolation pumps (8) and the pressure transmitter are both connected to the electrical control device (13).

10. The multi-material precision conveying system with multi-stage pumps in series according to claim 1 or 2, characterized in that: The material is liquid or a solid-liquid mixture.

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