Liquid mass metering device

Abstract

The utility model is suitable for fluid metering technical field provides a kind of liquid mass metering device, including oil storage tank, oil inlet pipeline assembly and liquid weighing scale;Liquid level meter and electric heating unit are provided in oil storage tank;Oil inlet pipeline assembly is connected on oil storage tank, and oil inlet pipeline assembly includes oil inlet pipeline, and oil inlet valve is installed on the oil inlet pipeline;Oil outlet pipeline is connected between oil storage tank and target equipment, and oil inlet metering pump, liquid flowmeter and pressure detection component are sequentially connected on oil outlet pipeline along liquid flow direction;The liquid weighing scale is connected on oil outlet pipeline, and the liquid flowing through liquid flowmeter is metered;It further includes control system, the signal of liquid flowmeter is metered, and the measurement result of liquid flowmeter is checked and fed back using the measurement value of liquid weighing scale in the measurement process.The utility model solves the problem that the existing liquid metering equipment has low measurement accuracy and weak temperature control ability in the application of high viscosity and temperature sensitive oil.

Description

Technical Field

[0001] This invention relates to the field of fluid metering technology, and in particular to a liquid mass metering device. Background Technology

[0002] In industrial fields such as rubber compounding and chemical production, accurate metering of liquid oils (such as aromatic oils) is a crucial step in ensuring product formulation consistency and process stability. Currently, commonly used liquid metering devices in the industry mostly employ volumetric metering or simple weighing methods, such as using fixed-volume hoppers, float-type level gauges, or ordinary flow meters for coarse control.

[0003] However, these traditional devices have significant shortcomings: their metering accuracy is generally low, making it difficult to meet the requirements of high-precision formulations. Furthermore, traditional devices do not fully consider the characteristics of oils such as high viscosity and strong temperature sensitivity, resulting in volume fluctuations caused by thermal expansion and contraction directly affecting the accuracy of mass conversion. In addition, most systems rely on manual intervention to complete the oil feeding, metering, and injection processes, resulting in low automation and susceptibility to operational errors.

[0004] In order to solve the above-mentioned technical problems, this utility model designs a liquid mass metering device. Utility Model Content

[0005] This utility model provides a liquid mass metering device, aiming to solve the problems of low metering accuracy and weak temperature control capability of existing liquid metering equipment in the application of high viscosity and temperature-sensitive oils. The technical solution is as follows: A liquid mass metering device includes an oil storage tank, an oil inlet pipeline assembly, and a liquid weighing scale. The oil storage tank is equipped with a level gauge and an electric heating unit. The oil inlet pipeline assembly is connected to the oil storage tank and includes an inlet pipe with an inlet valve installed on it. An outlet pipeline connects the oil storage tank and a target device, and an oil metering pump, a liquid flow meter, and a pressure detection assembly are sequentially connected to the outlet pipeline along the liquid flow direction. The liquid weighing scale is connected to the outlet pipeline and measures the liquid flowing through the liquid flow meter. The device also includes a control system electrically connected to the liquid flow meter, pressure detection assembly, oil inlet pipeline assembly, and oil metering pump. The control system controls the oil pipeline assembly and oil metering pump to operate according to instructions, measures the signal from the liquid flow meter, and verifies and provides feedback on the measurement result of the liquid flow meter using the measurement value from the liquid weighing scale during or after the measurement process.

[0006] Based on the above technical solution, the oil inlet pipeline assembly includes a first oil inlet pipe and a second oil inlet pipe. The diameter of the first oil inlet pipe is larger than that of the second oil inlet pipe. The control system is configured to control the first oil inlet pipe to perform large-flow oil inlet and control the second oil inlet pipe to perform small-flow fine-tuning.

[0007] Preferably, a return pipe is connected downstream of the oil metering pump to the oil outlet pipe, the return pipe returning to the oil storage tank, and an overflow valve is provided on the return pipe.

[0008] Preferably, a safety valve is also connected to the oil outlet pipe downstream of the liquid flow meter, and the outlet of the safety valve returns to the oil storage tank.

[0009] Beneficial effects Compared with the prior art, the beneficial effects of this utility model are: 1. Integrate a liquid weighing scale into the oil outlet pipeline. After each or periodic measurement, directly weigh the actual mass of the outflowing liquid and compare it with the converted value from the flow meter to form a measurement, verification, and feedback system. Only after passing the calibration is the system allowed to fill with oil, thus improving measurement accuracy.

[0010] 2. By installing an electric heating unit in the oil storage tank and adding a heating unit and insulation layer to the oil outlet pipeline, the oil temperature can be precisely maintained within the process setting range, which can reduce viscosity and keep the oil in good fluidity, thereby ensuring stable oil supply from the metering pump and improving the continuity and reliability of system operation. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other embodiments can be derived from the provided drawings without creative effort.

[0012] Figure 1 : A schematic diagram of the structure of this utility model; Figure 2 : A schematic diagram showing the positions of the oil metering pump, check valve, and overflow valve described in this utility model. Detailed Implementation

[0013] The present invention will be further described below with reference to the accompanying drawings and examples: The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0014] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0015] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0016] like Figure 1 As shown, a liquid mass metering device includes an oil storage tank 1, an oil inlet pipeline assembly 2, a liquid weighing scale 6, and a control system 8.

[0017] Oil storage tank 1 is a carbon steel structure with an outer galvanized thin steel plate. Oil flows through the pipeline of this oil storage tank into the storage space of the liquid metering station.

[0018] The oil storage tank 1 is equipped with a level gauge. Specifically, the level gauge in the oil storage tank 1 includes a first level gauge 11, a second level gauge 12 and a third level gauge 13 arranged from top to bottom, which are used to indicate the high level, low level and emergency shutdown level, respectively.

[0019] The first level gauge 11 serves as a high-level alarm point, triggering the control system to close the inlet valve when the oil level approaches the upper limit of the tank. The second level gauge 12 is the low-level threshold; when the oil level drops to the second level, the system can issue an oil replenishment prompt or automatically start the oil replenishment process. The third level gauge 13 is the minimum safe level; if the oil level falls below this limit, it indicates a severe oil shortage, and the system will immediately stop the oil injection pump. All three level signals are connected to the control system (PLC).

[0020] The oil inlet pipeline assembly 2 is connected to the oil storage tank 1. The oil inlet pipeline assembly 2 includes an oil inlet pipe and an oil inlet valve is installed on the oil inlet pipe.

[0021] In another embodiment, the oil inlet pipeline assembly 2 includes a first oil inlet pipe and a second oil inlet pipe, wherein the diameter of the first oil inlet pipe is larger than that of the second oil inlet pipe, and the control system 8 is configured to control the first oil inlet pipe to perform a large flow rate of oil inlet and control the second oil inlet pipe to perform a small flow rate fine adjustment.

[0022] The first inlet pipe allows for rapid injection of most of the required oil at a high flow rate. When the target metering value is approached, the flow is switched to the second inlet pipe for a slow, low-flow injection, achieving high-precision control. High-viscosity liquids (such as aromatic oils) exhibit inertia and response lag when flowing in pipelines. If only a single pipe is used, excess flow may still occur after closing the high-flow valve due to residual flow. The dual-pipeline design effectively reduces such errors by switching to the low-flow channel in advance.

[0023] An oil outlet pipe is connected between the oil storage tank 1 and the target equipment. An oil metering pump 31, a liquid flow meter 42, and a pressure detection component are sequentially connected to the oil outlet pipe along the liquid flow direction.

[0024] The oil metering pump 31 serves as the power source to flow the oil. The liquid flow meter 42 is located after the outlet of the oil metering pump 31 and can directly measure the actual output oil volume.

[0025] The pressure detection assembly includes a pressure gauge 41 for on-site indication and a pressure transmitter 43 for transmitting pressure signals to the control system 8.

[0026] Pressure gauge 41 monitors the pipeline pressure during the metering process, while liquid flow meter 42 is the core metering component of the system. Liquid flow meter 42 is a high-precision turbine flow meter capable of real-time monitoring and accumulating the volume of liquid passing through it. When oil flows through, it emits a pulse signal, each pulse representing a fixed volume (e.g., 1 liter / 1000 pulses). Pressure transmitter 43 transmits the pipeline liquid pressure to the analog acquisition module of the control system 8 (PLC) for real-time monitoring of the pipeline pressure, ensuring it remains within a reasonable range.

[0027] The Promass 80F is a Coriolis mass flow meter widely used in industrial processes for high-precision measurement of mass flow, density, and temperature of liquids, gases, or slurries.

[0028] While liquid flow meters (such as turbine or mass flow meters) offer high accuracy, long-term use can lead to measurement deviations due to wear, oil contamination, temperature drift, or aging of electronic components. The liquid weighing scale 6, as a high-precision weighing device (typically with an accuracy of ±0.01%), can directly measure the actual mass of the flowing liquid and compare it with the mass calculated by the liquid flow meter 42.

[0029] The liquid weighing scale 6 is connected to the oil outlet pipe, which has a valve. Opening the valve allows oil to flow to the liquid weighing scale 6, while closing the valve directs the oil to the final target device. The liquid flowing through the liquid flow meter 42 is measured. The liquid weighing scale 6 is connected to a recovery device, which includes a screw oil pump for recovering the measured oil. The recovery container can be connected to the oil storage tank 1.

[0030] The liquid weighing scale 6 is used to check and adjust the accuracy and stability of the metering system. It includes a high-precision weighing scale, a pressure holding device, an oil injector, and a screw oil pump to extract and recover the metered liquid into an oil tank.

[0031] The pressure-holding device maintains a stable pressure environment in the oil outlet pipe or measurement chamber during the measurement process. After the screw suction pump is calibrated, the weighed oil is efficiently and completely pumped back to the storage tank 1 or a dedicated recovery container.

[0032] The control system 8 is electrically connected to the liquid flow meter 42, the pressure detection component, the oil inlet pipeline component 2, and the oil metering pump 31. The control system 8 controls the oil pipeline component 2 and the oil metering pump 31 to work according to the instructions, measures the signal of the liquid flow meter 42, and verifies and provides feedback on the measurement result of the liquid flow meter 42 by using the measurement value of the liquid weighing scale 6 during or after the measurement process.

[0033] Downstream of the liquid weighing scale 6, an oil injection ball valve 7 is installed on the oil outlet pipeline. After successful verification, the control system 8 controls the oil injection ball valve 7 to open and inject oil into the target equipment.

[0034] After verification, the oil is fed into the target equipment. The oil ball valve 7 serves as the final control switch. Once the system has completed the accuracy verification of the metering results and confirmed that they are qualified, the oil is allowed to enter the target equipment.

[0035] Industrial oils such as aromatic oils have high viscosity and poor fluidity at room temperature, which can easily lead to difficulties in oil pump suction or cavitation, and excessive residue in pipelines, affecting batch consistency.

[0036] To address the aforementioned issues, an electric heating unit 14 is installed within the oil storage tank 1. Both the outer wall of the oil storage tank 1 and the oil outlet pipe are covered with an insulation layer, which can be made of polyurethane. The electric heating unit 14 includes an electric heating wire and a temperature sensor, and a heating unit is installed on the oil outlet pipe. Through heating and insulation by the electric heating unit 14 within the oil storage tank 1 and the oil outlet pipe, the oil temperature is stably controlled within a set range (e.g., 50℃±1℃), which can reduce viscosity, improve fluidity, and ensure smooth pumping, stable flow rate, and reliable metering.

[0037] Temperature sensors are installed in the middle of the oil storage tank and the middle section of the oil outlet pipe to detect temperature.

[0038] To prevent system overpressure from damaging the equipment and to maintain a stable outlet pressure of the oil metering pump, ensuring the accuracy of the flow meter and the safe operation of the system, a return pipe is connected downstream of the oil metering pump 31 to the oil outlet pipe. The return pipe returns to the oil storage tank 1 and is equipped with an overflow valve 33.

[0039] like Figure 2 As shown, a one-way valve 32 is also provided downstream of the oil metering pump 31 in the oil outlet pipeline. The direction of the one-way valve 32 is from the metering pump 31 to the target equipment.

[0040] Downstream of the oil metering pump 31, the oil outlet pipe is also connected to a return pipe, which returns to the oil storage tank 1. An overflow valve 33 is provided on the return pipe.

[0041] When the pressure in the oil outlet pipeline rises to the set threshold due to downstream blockage, valve closure, or sudden viscosity change, the overflow valve automatically opens, guiding the excess oil back to the oil storage tank 1 through the return pipeline.

[0042] When this device is in operation, The control system 8 activates the electric heating unit 14 inside the oil storage tank 1 and the heating unit on the oil outlet pipe, working in conjunction with the insulation layer to stabilize the oil temperature at the set value. This reduces the oil viscosity and ensures fluidity. The level gauge confirms that the oil level in the storage tank is sufficient and within a safe range.

[0043] The control system 8 opens the inlet valve of the first inlet pipe, rapidly injecting most of the required oil volume into the metering pipeline or intermediate metering chamber at a high flow rate. When the target mass is approached, the high-flow valve is closed, and the system switches to the second inlet pipe for fine-tuning with a low flow rate to avoid overshoot. The oil flows through the liquid flow meter 42 (such as a high-precision turbine flow meter), generating pulse signals. The control system 8 calculates the volume based on the number of pulses and converts it into mass by combining the density at the current temperature.

[0044] The control system 8 closes the downstream oil injection ball valve 7 and opens the valve leading to the liquid weighing scale 6, allowing oil to flow into the scale. The scale directly measures the actual oil mass and compares it with the result calculated by the liquid flow meter 42. If the error is within the allowable range, the calibration is considered successful. If the error exceeds the allowable range, an alarm is triggered, and parameter correction or manual intervention may be required. After calibration, the screw suction pump is started to pump the oil from the weighing scale back to the storage tank 1 or the recovery bucket.

[0045] After the control system 8 confirms the successful verification, it opens the oil injection ball valve 7, and the oil is delivered to the target equipment such as the internal mixer.

[0046] The purpose of the liquid weighing scale 6 is to measure a portion of the oil to provide a true reference for the liquid flow meter, enabling the detection and correction of flow meter errors. Calibration of the flow meter ensures the accuracy of subsequent measurements.

[0047] It should be noted that the control system, level gauge, oil metering pump, liquid flow meter, pressure gauge, liquid weighing scale, and oil ball valve in this embodiment are all general standard parts or components known to those skilled in the art. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0048] The present invention has been described above by way of example, but the present invention is not limited to the specific embodiments described above. Any modifications or variations made based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A liquid mass metering device, characterized in that: The system includes an oil storage tank (1), an oil inlet pipeline assembly (2), and a liquid weighing scale (6); the oil storage tank (1) is equipped with a level gauge and an electric heating unit (14); the oil inlet pipeline assembly (2) is connected to the oil storage tank (1), and the oil inlet pipeline assembly (2) includes an oil inlet pipe, on which an oil inlet valve is installed; an oil outlet pipeline connects the oil storage tank (1) and the target equipment, and an oil metering pump (31), a liquid flow meter (42), and a pressure detection assembly are sequentially connected along the liquid flow direction on the oil outlet pipeline; the liquid weighing scale (6) is connected to... The liquid flowing through the liquid flow meter (42) is measured on the oil outlet pipeline; it also includes a control system (8), which is electrically connected to the liquid flow meter (42), the pressure detection component, the oil inlet pipeline component (2) and the oil metering pump (31); the control system (8) controls the oil pipeline component (2) and the oil metering pump (31) to work according to the instructions, measures the signal of the liquid flow meter (42), and after the measurement is completed, uses the measurement value of the liquid weighing scale (6) to verify and feedback the measurement result of the liquid flow meter (42).

2. The liquid mass metering device according to claim 1, characterized in that: The oil inlet pipeline assembly (2) includes a first oil inlet pipe and a second oil inlet pipe, wherein the diameter of the first oil inlet pipe is larger than that of the second oil inlet pipe.

3. The liquid mass metering device according to claim 1, characterized in that: Downstream of the oil metering pump (31), the oil outlet pipe is also connected to a return pipe, which returns to the oil storage tank (1). An overflow valve (33) is provided on the return pipe.

4. A liquid mass metering device according to claim 1, characterized in that: A safety valve (5) is also connected downstream of the liquid flow meter (42) on the oil outlet pipe, and the outlet of the safety valve (5) returns to the oil storage tank (1).

5. A liquid mass metering device according to claim 1, characterized in that: The pressure detection assembly includes a pressure gauge (41) for on-site indication and a pressure transmitter (43) for transmitting pressure signals to the control system (8).

6. A liquid mass metering device according to claim 4, characterized in that: The liquid weighing scale (6) is connected to a recycling device, which includes a screw oil pump for pumping the metered liquid back to the storage tank (1) or a special recycling bucket.

7. A liquid mass metering device according to claim 4, characterized in that: The oil outlet pipe is also equipped with an oil injection ball valve (7) downstream of the liquid weighing scale (6); after the verification is successful, the control system (8) controls the oil injection ball valve (7) to open and inject oil into the target equipment.

8. A liquid mass metering device according to claim 4, characterized in that: The level gauges in the oil storage tank (1) include a first level gauge (11), a second level gauge (12) and a third level gauge (13) arranged from top to bottom, which are used to indicate the high level, low level and emergency shutdown level, respectively.

9. A liquid mass metering device according to claim 1, characterized in that: The outer wall of the oil storage tank (1) and the oil outlet pipe are both covered with a heat insulation layer. The electric heating unit (14) includes an electric heating wire and a temperature sensor. The oil outlet pipe is equipped with a heating unit.

10. A liquid mass metering device according to claim 1, characterized in that: The oil outlet pipeline is also equipped with a one-way valve (32) downstream of the oil metering pump (31), and the direction of the one-way valve (32) is from the metering pump (31) to the target equipment.

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