A dosing liquid delivery system for pharmaceutical production

Abstract

The utility model discloses a kind of quantitative liquid delivery systems for medicament production, it is related to chemical medicament production equipment field, solve the problem such as low precision, automation and security deficiency of existing conveying mode.System includes liquid storage unit (food grade material pure water tank), power delivery unit (stainless steel jet type self-priming pump), pipeline unit (stainless steel / food grade plastic pipeline and solenoid valve), metering detection unit (flow measuring instrument and input type static pressure liquid level meter suitable for different pure water conductivity) and control unit (including PLC, man-machine interface control electric box).Through closed-loop control and advance compensation logic, combined with accurate measurement, pure water conveying error is ≤±1%, realize whole-process automation, can also monitor pump overload and other faults and trigger alarm and protection action, adapt to multiple scenarios, meet medicament production hygiene and precision requirement.

Description

Technical Field

[0001] This utility model relates to the technical field of chemical pharmaceutical production equipment, and in particular to a quantitative liquid delivery system for pharmaceutical production. Background Technology

[0002] In the production of chemical agents such as magnesium alloy conversion coatings, aluminum alloy passivating agents, and high-efficiency cleaning agents, a precise quantity of pure water must be accurately delivered to a mixing tank for mixing to ensure the accuracy of the agent composition ratio. Traditional delivery methods have the following shortcomings: Manually operating valves and observing flow meters results in large errors and low efficiency. Some automated systems lack robust control logic and safety protection, making it difficult to meet accuracy requirements within ±1%. The metering accuracy for low conductivity pure water (such as ultrapure water) is insufficient, and there is a lack of equipment condition monitoring and predictive maintenance capabilities.

[0003] Therefore, there is an urgent need for a quantitative liquid delivery system that is highly accurate, automated, and safe. Utility Model Content

[0004] To overcome the shortcomings mentioned above, this utility model aims to provide a technical solution that can solve the above problems.

[0005] This utility model provides a quantitative liquid delivery system for pharmaceutical production, including a liquid storage unit, a power delivery unit, a pipeline unit, a metering and detection unit, and a control unit; The liquid storage unit includes a pure water tank for storing pure water; The power delivery unit includes a self-priming pump for drawing and delivering pure water from the pure water tank; The pipeline unit includes an inlet pipe and an outlet pipe connecting the pure water tank, the self-priming pump and the mixing tank, as well as a solenoid valve installed on the outlet pipe for controlling the pipeline opening and closing. The metering and detection unit includes a flow meter installed on the outlet pipe for real-time detection of pure water volume flow rate, and a hydrostatic level gauge installed in the pure water tank for detecting water level height. The control unit includes a control box integrating a PLC (Programmable Logic Controller), an automatic pump controller, and a human-machine interface (HMI). The PLC is used to receive set parameters, acquire signals from the flow meter and the hydrostatic level gauge, and output control commands to control the start and stop of the self-priming pump and the opening and closing of the solenoid valve. The human-machine interface is used to set the target conveying volume and display the system operating status.

[0006] Furthermore, the pure water tank is made of food-grade stainless steel or fiberglass.

[0007] Furthermore, the inlet and outlet pipes are made of stainless steel or food-grade plastic.

[0008] Furthermore, the flow meter is one of an electromagnetic flow meter, a turbine flow meter, or an ultrasonic flow meter.

[0009] Furthermore, the installation position of the flow meter satisfies the requirement that the length of the upstream straight pipe section is ≥10 times the pipe diameter, the length of the downstream straight pipe section is ≥5 times the pipe diameter, and the pipe diameter of the vertical straight pipe section matches the sensor diameter.

[0010] Furthermore: the flow meter is a split-type electromagnetic flow meter, including a sensor and a converter; the split-type electromagnetic flow meter detects the volumetric flow rate of pure water based on Faraday's law of electromagnetic induction, the sensor is installed in the middle section of the vertical straight section of the outlet pipe, and the converter is connected to the sensor through a shielded cable.

[0011] Furthermore, the shielded cable between the sensor and the converter is 0.5 to 100 meters long, and the outer layer of the cable is wrapped with a metal shielding layer to resist electromagnetic interference.

[0012] Furthermore, the control box is also equipped with circuit breakers, relays, and terminals to ensure circuit safety and signal transmission.

[0013] Furthermore, the PLC is also used to trigger audible and visual alarms and execute protective actions when the system experiences pump overload, pipeline blockage, or abnormal liquid level.

[0014] Compared with the prior art, the beneficial effects of this utility model are: ① Significantly improved delivery accuracy: Under the conditions of a delivery volume of 500L, a pure water medium conductivity of ≥5μS / cm, and a flow velocity of ≤2m / s, the combined design of "high-precision flow meter + PLC closed-loop control + advance compensation logic" is adopted. This addresses key factors affecting accuracy, such as solenoid valve closing lag and pipeline flow fluctuations. The PLC collects flow signals in real time and calculates the lag volume, triggering the valve closing command in advance. Combined with the selection of flow meters adapted to pure water with different conductivity (such as electromagnetic flow meters adapted to pure water with a conductivity of around 10μS / cm, and ultrasonic flow meters adapted to ultrapure water), the delivery error can be stably controlled within ±1%, fully meeting the requirements of high-precision pharmaceutical production for raw material ratios and effectively ensuring the consistency of pharmaceutical performance.

[0015] ② High level of automation and intelligence: The system achieves full automation of the entire process from parameter setting to pre-detection, quantitative delivery, and stop feedback. Operators only need to input the target delivery volume through the human-machine interface, and the system can autonomously complete water level detection, coordinated control of pumps and solenoid valves, and real-time flow monitoring, significantly reducing manual intervention and increasing production efficiency by more than 30%. At the same time, it integrates fault diagnosis and predictive maintenance functions, which can monitor pump overload, pipeline blockage, abnormal flow meter signals, etc. in real time, trigger audible and visual alarms, and execute targeted protection actions (such as pump stoppage, valve closure, and backflushing). It can also predict maintenance needs such as flow meter calibration and electrode cleaning based on historical data, reducing operation and maintenance costs and the risk of production interruption.

[0016] ③ High safety and reliability: A multi-level safety protection system is constructed. The static pressure level gauge monitors the water level in the pure water tank in real time to avoid pump damage caused by low liquid level. The solenoid valve response time is ≤0.5s, which can quickly cut off the pipeline to prevent over-transmission. The electrical system is equipped with circuit breakers, relays and overload / undervoltage protection modules to effectively prevent circuit failures. At the same time, the liquid storage unit and pipeline unit are made of food-grade stainless steel, fiberglass or corrosion-resistant plastics and other materials that meet hygiene standards to eliminate pure water pollution and cross-contamination and meet the safety and hygiene requirements of pharmaceutical production.

[0017] ④ Excellent adaptability and expandability: Electromagnetic flow meters, turbine flow meters, or ultrasonic flow meters can be flexibly selected according to the characteristics of pure water (conductivity, impurity content), and the metering stability is ensured by optimizing the flow meter installation method (such as vertical straight pipe section installation and shielded cable anti-interference). It supports the expansion of bypass valves and backwash pumps, remote control modules, energy consumption monitoring and energy-saving control modules according to production needs. It can adapt to the production scenarios of different agents such as magnesium alloy conversion film and aluminum alloy passivating agent, and meet the development trend of modern industrial automation and energy conservation and environmental protection. It has a wide range of applications and strong practicality.

[0018] In summary, this quantitative liquid delivery system for pharmaceutical production, through "high-precision flow meter + PLC closed-loop control + advance compensation", ensures delivery error ≤ ±1%, achieves full-process automation and integrates fault diagnosis, and also features multi-layer safety protection, adapts to various pure water characteristics, and meets the high-precision requirements of pharmaceutical production.

[0019] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] 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 some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the pipeline unit of this utility model, which connects the liquid storage unit, the power delivery unit and the stirring tank respectively; Figure 2 This is a schematic diagram of the pipeline unit and metering and testing unit of this utility model; Figure 3 This is a schematic diagram of the overall structure of this utility model; Figure 4 This is a schematic diagram of the overall system flow of this utility model; Figure 5 This is the fault monitoring and protection logic diagram of this utility model.

[0022] The reference numerals and names in the figure are as follows: 10 Liquid storage unit; 20 Power transmission unit; 30 Piping unit; 31 Inlet pipe; 32 Outlet pipe; 33 Solenoid valve; 40 Metering and detection unit; 41 Flow meter; 42 Sensor; 43 Shielded cable; 50 Stirring tank. Detailed Implementation

[0023] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] Please see Figures 1 to 5 In this embodiment of the present invention, a quantitative liquid delivery system for pharmaceutical production includes a liquid storage unit 10, a power delivery unit 20, a pipeline unit 30, a metering and detection unit 40, and a control unit. The liquid storage unit 10 includes a pure water tank for storing pure water; The power delivery unit 20 includes a stainless steel jet-type self-priming pump for drawing and delivering pure water from the pure water tank. The pipeline unit 30 includes an inlet pipe 31 and an outlet pipe 32 that connect the pure water tank, the stainless steel jet self-priming pump and the mixing tank 50, as well as a solenoid valve 33 installed on the outlet pipe 32 for controlling the pipeline opening and closing. The metering and detection unit 40 includes a flow meter 41 installed on the water outlet pipe 32 for real-time detection of pure water volume flow rate, and a hydrostatic level gauge installed in the pure water tank for detecting water level height. The control unit includes a control box integrating a PLC (Programmable Logic Controller), an automatic pump controller, and a human-machine interface (HMI). The PLC receives set parameters, acquires signals from the flow meter 41 and the hydrostatic level gauge, and outputs control commands to control the start and stop of the stainless steel jet self-priming pump and the opening and closing of the solenoid valve 33. The HMI is used to set the target delivery volume and display the system operating status. The pure water tank is made of food-grade stainless steel or fiberglass. The inlet pipe 31 and outlet pipe 32 are made of stainless steel or food-grade plastic. The flow meter 41 is one of an electromagnetic flow meter, a turbine flow meter, or an ultrasonic flow meter. The installation position of the flow meter 41 meets the requirements that the upstream straight pipe section length is ≥10 times the pipe diameter, the downstream straight pipe section length is ≥5 times the pipe diameter, and the diameter of the vertical straight pipe section matches the diameter of the sensor 42.

[0025] Specifically, electromagnetic flowmeters are suitable for pure water media with conductivity ≥ 5 μS / cm, turbine flowmeters are suitable for pure water media with low impurity content and stable viscosity, and ultrasonic flowmeters are suitable for pure water media with low conductivity < 5 μS / cm.

[0026] like Figure 2 and Figure 4 As shown, preferably, in another embodiment: The flow meter 41 is a split-type electromagnetic flow meter, including a sensor 42 and a converter. The split-type electromagnetic flow meter detects the volumetric flow rate of pure water based on Faraday's law of electromagnetic induction. The sensor 42 is installed in the middle section of the vertical straight pipe section of the outlet pipe 32. The converter is connected to the sensor 42 through a shielded cable 43.

[0027] Specifically, in existing automated systems, the selection and installation of the flow meter 41 significantly affects measurement accuracy. For pure water with a conductivity of approximately 10 μS / cm in pharmaceutical production, electromagnetic flow meters are a suitable choice. However, traditional integrated electromagnetic flow meters are susceptible to environmental interference in high-temperature and high-humidity production environments. While a split design can solve this problem, it lacks specific adaptation solutions for pharmaceutical production scenarios (such as vertical pipeline installation and remote signal anti-interference).

[0028] Therefore, a split-type electromagnetic flowmeter is adopted. The sensor 42 can withstand the high temperature and high humidity environment of the production site. The converter is integrated into the control box and transmits signals remotely through the shielded cable 43, with a maximum spacing of 100 meters, which can meet the layout requirements of the pharmaceutical production workshop. For pure water with a conductivity of about 10 μS / cm, the electromagnetic flowmeter is not affected by temperature, pressure and viscosity, and there is no pressure loss, ensuring stable measurement accuracy. The sensor 42 is installed in the vertical straight pipe section, which is in line with the requirements of the upstream and downstream straight pipe sections, reduces flow interference, and further improves measurement accuracy.

[0029] Secondly, the measurement accuracy of the split-type electromagnetic flowmeter is ±0.5%~±1.0%, and it is suitable for pure water media with a conductivity ≥5μS / cm (such as pure water with a conductivity of about 10μS / cm in this system).

[0030] like Figures 1 to 4 As shown, preferably, in another embodiment: The shielded cable 43 between the sensor 42 and the converter is 0.5 to 100 meters long, and the cable is wrapped with a metal shielding layer to resist electromagnetic interference. The control box is also equipped with circuit breakers, relays, and terminals to ensure circuit safety and signal transmission. The PLC is also used to trigger audible and visual alarms and execute protective actions when the system experiences pump overload, pipeline blockage, or abnormal liquid level faults.

[0031] Specifically, the PLC is also used to immediately control the self-priming pump to stop running and close the solenoid valve 33 when the system experiences pump overload (current > 1.2 times the rated value); when pipeline blockage occurs (pump current exceeds 1.1 times the rated value for 10 seconds), stop the self-priming pump, open the bypass valve (if set) and close the solenoid valve 33; when abnormal liquid level occurs (pure water tank level is lower than the minimum safe water level), stop the self-priming pump without opening the solenoid valve 33, and trigger an audible and visual alarm.

[0032] In addition, the pipeline unit 30 also includes a bypass valve installed on the outlet pipe 32, and a backwash pump connected to the bypass valve. The PLC is used to control the start of the backwash pump and the opening of the bypass valve when the pipeline is blocked.

[0033] Example 1: Conventional Pure Water Quantitative Delivery System Based on Electromagnetic Flowmeter This embodiment is used to quantitatively deliver 500L of pure water to a mixing tank 50 used in the production of magnesium alloy conversion films. The configuration of each unit and the workflow of the system are as follows: 1. Unit Configuration Storage Unit 10: The pure water tank is made of 304 food-grade stainless steel with a volume of 2000L and polished inner wall; the top is equipped with a water inlet / vent hole, and the side is equipped with an immersion hydrostatic level gauge (range 0~2m) to monitor the water level.

[0034] Power transmission unit 20: Stainless steel jet self-priming pump, flow rate 0~10m3 / h, head 20m, self-priming height 5m, suitable for pure water medium.

[0035] Piping unit 30: Inlet pipe 31 / outlet pipe 32 are DN50 stainless steel pipes; DN50 normally closed solenoid valve 33 (response time ≤0.5s) is installed on outlet pipe 32.

[0036] Metering and detection unit 40: Flow meter 41 is an electromagnetic flow meter (accuracy ±0.5%), installed on the outlet pipe 32, meeting the requirements of "upstream straight pipe section 10×DN50=500mm, downstream straight pipe section 5×DN50=250mm"; the static pressure level gauge is an immersion static pressure level gauge.

[0037] Control unit: The control box integrates a Siemens S7-1200 PLC, a 7-inch touch screen HMI, an automatic pump controller (including overload / undervoltage protection), as well as circuit breakers, relays, and terminal blocks.

[0038] 2. Workflow Parameter settings: The operator inputs the target volume "500L" through the HMI, and the parameter is transmitted to the PLC.

[0039] Pre-detection: The PLC detects the water level through the hydrostatic level gauge. If the water level is ≥ the minimum safe water level (corresponding to a volume of 500L), it sends an "open" command to the solenoid valve 33; otherwise, it triggers a "water shortage alarm".

[0040] Quantitative delivery and early valve closure compensation: After the solenoid valve 33 is opened, the PLC starts the self-priming pump, and pure water is delivered to the mixing tank 50; the electromagnetic flow meter provides real-time feedback on the cumulative volume.

[0041] The measured closing lag time of solenoid valve 33 is τ=0.8s. The instantaneous flow rate is taken as an average flow velocity of 2m / s (DN50 pipe cross-sectional area ≈0.00196m2, instantaneous flow rate ≈0.00392m3 / s (cubic meters per second) = 14.112m3 / h (cubic meters per hour)). The lag volume Qτ=14.112m3 / h×(0.8 / 3600)h≈0.00314m3≈3.14L. Therefore, when the cumulative flow reaches 500L-3.14L=496.86L, the PLC sends the "valve close" command in advance, and the final delivery volume is close to 500L.

[0042] Stop and Feedback: After the pump stops and the valve is closed, the HMI displays "Delivery Complete" and records the actual volume (e.g., 499.5L); if the pump is overloaded (current > 1.2 times the rated value), the PLC immediately stops the pump, closes the valve, and issues an audible and visual alarm.

[0043] II. Example 2: Pure water delivery system for magnesium alloy conversion membrane production based on split-type electromagnetic flowmeter (for pure water with conductivity of 10 μS / cm, quantitative delivery of 500L to a mixing tank 50) 1. Unit Configuration Measurement and testing unit 40: Split-type electromagnetic flowmeter: Sensor 42 (DN50, 316 stainless steel electrode, PTFE lining) is installed in the middle section of the vertical straight pipe section of the outlet pipe 32 (pipe length 1m, pipe diameter 50mm), meeting the requirements of "upstream straight pipe section 500mm (10×DN50), downstream straight pipe section 250mm (5×DN50)"; the converter (accuracy ±0.5%) is integrated in the control box and connected to sensor 42 through a 20-meter shielded cable 43 (with metal shielding layer), with cable grounding resistance <10Ω; the static pressure level gauge is an immersion static pressure level gauge.

[0044] The remaining units are the same as before. The control unit uses a Siemens S7-1200 PLC, and the HMI displays "cumulative flow, sensor 42 signal strength, and cable connection status" in real time.

[0045] 2. Workflow Because the conductivity of pure water is 10μS / cm≥5μS / cm, the electromagnetic flowmeter outputs a stable signal, and the PLC collects the cumulative flow every 10ms. Early valve closure compensation: The measured lag time of solenoid valve 33 was 0.8s, the instantaneous flow rate was 14.11m3 / h, and the lag volume was 3.14L. Therefore, the valve was closed early when the cumulative flow reached 496.86L, and the final actual delivery volume was 499.7L, with an error of 0.06%. High temperature environment adaptability: Sensor 42 can withstand workshop temperature of 60℃, converter works stably in electrical box (room temperature 25℃), shielded cable 43 effectively isolates electromagnetic interference from workshop motors, signal fluctuation ≤0.1%.

[0046] III. Example 3: Application of split-type electromagnetic flowmeter with long-distance signal transmission (for the production of aluminum alloy trivalent chromium passivating agent, the workshop layout requires a distance of 80 meters between the sensor 42 and the control box). 1. Key Adjustments Measurement and detection unit 40: Sensor 42 and converter are connected via an 80-meter shielded cable 43, with a signal amplifier installed in the middle of the cable (one every 50 meters) to ensure signal attenuation ≤5%; Control logic: The PLC adds a "signal strength monitoring" module, which triggers a "cable inspection reminder" when the signal strength is less than 90%.

[0047] 2. Application Effects At a distance of 80 meters, the flow measurement error is still controlled within ±0.8%; on one occasion, a loose cable joint caused the signal strength to drop to 85%, and the system promptly reminded the operator to handle the situation to avoid measurement deviation.

[0048] IV. Example 4: Low-Conductivity Pure Water Delivery System Based on Ultrasonic Flow Meter This embodiment focuses on ultrapure water (conductivity < 5 μS / cm) for production without chromium passivating agents. The flow meter type 41 is adjusted, while the remaining units are similar to those in Embodiment 1. 1. Measurement and testing unit 40: Flow meter 41 is a time-difference ultrasonic flow meter (accuracy ±1.0%), which is suitable for low conductivity media and has the same installation requirements as electromagnetic flow meters.

[0049] 2. Control Logic Optimization: Due to the slightly slow signal response of the ultrasonic flow meter, the measured lag time τ = 1.0s, and the lag volume Qτ = 14.112m³ / h × (1.0 / 3600)h ≈ 0.00392m³ ≈ 3.92L. Therefore, when the cumulative flow reaches 500L - 3.92L = 496.08L, the PLC closes the valve in advance to ensure accuracy.

[0050] V. Example 5: Intelligent Conveying System with Fault Diagnosis and Predictive Maintenance This embodiment enhances the intelligence of the control unit based on Embodiment 1: 1. Intelligent Function Expansion Control Unit: The PLC has a built-in fault diagnosis algorithm that predicts maintenance needs such as "electrode cleaning" and "pipeline unblocking" by detecting signal fluctuations in the flow meter 41 (such as noise from electromagnetic flow meter electrode contamination) and changes in pump current (such as increased current due to pipeline blockage). At the same time, it predicts the flow meter calibration cycle by using historical error trends and pushes maintenance reminders to the HMI in advance.

[0051] Additional hardware: A bypass valve and a backwash pump (optional) are added to the outlet pipe 32. The piping unit 30 can also be equipped with a bypass valve on the outlet pipe 32 as needed. The bypass valve is connected to the backwash pump for backwashing operation when the pipeline is blocked.

[0052] 2. Application Effects: When the electromagnetic flowmeter electrode contamination causes the measurement error to exceed 0.8%, the HMI will pop up an "electrode cleaning reminder"; if the pipeline blockage causes the pump current to exceed 1.1 times the rated value for 10 seconds, the system will automatically stop the pump, open the bypass valve and start the backwash pump. After the backwash is completed, the delivery will be automatically restored, reducing manual intervention and downtime.

[0053] As can be seen from the above embodiments, the quantitative liquid delivery system of the present invention can flexibly adapt the flow meter type and control logic according to the characteristics (conductivity, impurities) and accuracy requirements of pure water for different pharmaceutical production, so as to achieve high-precision, automated and intelligent quantitative delivery and provide reliable guarantee for chemical pharmaceutical production.

[0054] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

Claims

1. A quantitative liquid delivery system for pharmaceutical production, characterized in that, It includes a liquid storage unit (10), a power transmission unit (20), a pipeline unit (30), a metering and detection unit (40), and a control unit; The liquid storage unit (10) includes a pure water tank for storing pure water; The power delivery unit (20) includes a self-priming pump for drawing and delivering pure water from the pure water tank; The pipeline unit (30) includes an inlet pipe (31) and an outlet pipe (32) connecting the pure water tank, the self-priming pump and the mixing tank (50), as well as a solenoid valve (33) installed on the outlet pipe (32) for controlling the opening and closing of the pipeline. The metering and detection unit (40) includes a flow meter (41) installed on the water outlet pipe (32) for real-time detection of pure water volume flow rate, and a hydrostatic level gauge installed in the pure water tank for detecting water level height. The control unit includes a control box integrating a PLC, an automatic pump controller and a human-machine interface. The PLC is used to receive set parameters, collect signals from the flow meter (41) and the static pressure level gauge, and output control commands to control the start and stop of the self-priming pump and the opening and closing of the solenoid valve (33). The human-machine interface is used to set the target conveying volume and display the system operating status.

2. The quantitative liquid delivery system for pharmaceutical production according to claim 1, characterized in that, The pure water tank is made of food-grade stainless steel or fiberglass.

3. A quantitative liquid delivery system for pharmaceutical production according to claim 1, characterized in that, The inlet pipe (31) and outlet pipe (32) are made of stainless steel or food-grade plastic.

4. A quantitative liquid delivery system for pharmaceutical production according to claim 1, characterized in that, The flow meter (41) is one of an electromagnetic flow meter, a turbine flow meter, or an ultrasonic flow meter.

5. A quantitative liquid delivery system for pharmaceutical production according to claim 4, characterized in that, The installation position of the flow meter (41) meets the requirements that the upstream straight pipe section length is ≥10 times the pipe diameter, the downstream straight pipe section length is ≥5 times the pipe diameter, and the pipe diameter of the straight pipe section matches the diameter of the sensor (42).

6. A quantitative liquid delivery system for pharmaceutical production according to claim 5, characterized in that, The flow meter (41) is a split-type electromagnetic flow meter, including a sensor (42) and a converter; the sensor (42) is installed in the middle section of the vertical straight pipe section of the outlet pipe (32), and the converter is connected to the sensor (42) through a shielded cable (43).

7. A quantitative liquid delivery system for pharmaceutical production according to claim 6, characterized in that, The shielded cable (43) between the sensor (42) and the converter is 0.5 to 100 meters long, and the outer layer of the cable is wrapped with a metal shielding layer to resist electromagnetic interference.

8. A quantitative liquid delivery system for pharmaceutical production according to claim 1, characterized in that, The control box is also equipped with circuit breakers, relays, and terminals to ensure circuit safety and signal transmission.

9. A quantitative liquid delivery system for pharmaceutical production according to claim 1, characterized in that, The PLC is also used to trigger audible and visual alarms and execute protective actions when the system experiences pump overload, pipeline blockage, or abnormal liquid level.

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