Material tank weighing sensorIt is used in industrial production forAccurately measure the weight (or mass) of materials in the material tankThe core components are widely used in fields such as chemical, food, pharmaceutical, building materials, and energy. Its essence is to separate the material tank and its internal materialsConvert gravity (load) into measurable electrical signals (such as millivolts, currents, or digital signals)Through signal processing and calculation, the final output of material weight data is provided for the production processIngredient control, inventory management, safety monitoringProvide key evidence. From the followingWorking principle, structural composition, key technical characteristics, and typical application scenariosAnalyze from four aspects.

1、 Working principle: Conversion from gravity to electrical signals

The core function of a weighing sensor isPower electric conversionThe basic principle is based onMechanical equilibrium and changes in electrical parametersThe association. At present, the mainstream material tank weighing sensors in industry are mostlyResistance strain type weighing sensor(accounting for over 90%), in addition toPiezoelectric, piezoelectric, capacitiveSelect the appropriate type based on specific scenario requirements. The following focuses on the working principle of resistance strain gauges (other types of principles will be supplemented later).

（1） The Core Mechanism of Resistance Strain Gauge Weighing Sensor

The essence of a resistance strain sensor is to useDeformation of metal elastomer → Resistance change of strain gauges → Output signal of bridge circuitThe three-level conversion achieves force electricity conversion, and the specific steps are as follows:

　　Elastic deformation under stress​

The weight of the material tank is transmitted to the sensor through supporting structures such as weighing modules, cantilever beams, or column supportselastomer(Usually beam, spoke, or shear beam structures made of alloy steel or aluminum alloy). When the material in the tank increases, the elastic body is subjected to downward tension or pressure (depending on the installation method), resulting in small elastic deformation (deformation amount is usually tens to hundreds of microstrains, that is, 1 microstrain=10 ⁻⁶ mm/mm).

　　Strain gauge resistance variation​

The key stress bearing parts of elastomers, such as the curved surface of beams or the axial surface of columns, are bonded withResistance strain gaugeA metal foil grid or metal wire grid made of sensitive materials such as copper or nickel chromium alloy, with an initial resistance value of about 120 Ω, 350 Ω, or 1000 Ω. When the elastic body deforms, the strain gauges are stretched or compressed together, and their geometric dimensions (length, cross-sectional area) change. At the same time, the internal lattice structure is distorted, resulting in a linear change in resistance value (followingStrain resistance effectThe formula is Δ R/R=K ⋅ ε, where Δ R is the change in resistance, R is the initial resistance, K is the sensitivity coefficient (approximately 2-5), and ε is the strain value.

　　Output signal of bridge circuit​

Multiple strain gauges are combined according to a specific bridge structure (such as a Wheatstone bridge): usually, two strain gauges are pasted on the tension side (increasing resistance), and the other two are pasted on the compression side (decreasing resistance) to form a differential bridge. When an elastic body is subjected to force, the resistance of the strain gauge on the tension side increases, the resistance on the compression side decreases, the bridge loses balance, and the output is proportional to the strain valueMillivolt level voltage signal(For example, outputting 10-100mV under full scale load). After being amplified by an amplifier (such as an instrument amplifier), the signal is converted into a standard signal (such as 4-20mA current, 0-10V voltage, or digital signal RS485), and finally transmitted to PLC, DCS, or weighing instruments to display the weight value.

（2） Working principle of other types of sensors (supplementary)

　　Pressure magnetic sensorUtilizing the magnetic permeability change (magnetoresistance effect) of ferromagnetic materials under stress, the force can be indirectly measured by detecting changes in coil inductance or impedance. It is suitable for large tonnage material tanks (such as hundreds of tons), with strong anti-interference ability but low accuracy (± 0.5%~1%).

　　Piezoelectric sensorBased on piezoelectric crystals (such as quartz) that generate charges under pressure (positive piezoelectric effect) and output charge signals proportional to pressure (requiring a charge amplifier), it is suitable for dynamic weighing (such as rapid feeding processes), but has poor static stability.

　　Capacitive sensorBy measuring the changes in the distance between the electrode plates (due to the weight of the material tank causing the deformation of the elastic body and changing the gap between the capacitor electrode plates), the capacitance value is changed, and a force related capacitance signal is output, which has high accuracy but is easily affected by environmental humidity.

2、 Structural composition: complete link from sensors to weighing system

The practical application of the material tank weighing sensor is not a single component, but rather a combination ofSensor body+support structure (weighing module)+signal processing and display unitThe complete system consists of:

　　Sensor bodyCore component, directly sensing the weight of the material tank and outputting electrical signals (such as the elastic body of the resistance strain sensor+strain gauge+bridge).

　　weighing module: Pass the vertical load of the material tank throughFixed pivot, floating pivot or guiding pivotUniform transmission to the sensor (avoiding lateral force and torque interference), common installation methods include:

　　Cantilever beam typeSuitable for small material tanks (capacity<1 ton), sensors are installed on the cantilever structure at the bottom or side of the tank;

　　Column/spoke typeSuitable for medium to large-sized material tanks (capacity 1-50 tons), with sensors supporting the tank vertically to withstand axial pressure;

　　Shear beam typeBy measuring shear force (rather than bending force), the ability to resist lateral interference is improved, suitable for environments with high vibration (such as near conveyor lines).

　　signal processing unitIncluding amplifiers, filters, analog-to-digital converters (ADCs), and microprocessors, used to convert millivolt level raw signals into standard signals (such as 4-20mA) and compensate for temperature drift, nonlinear errors, etc. (through built-in calibration algorithms).

　　Display and Control TerminalSuch as weighing instruments (displaying real-time weight and cumulative weight), PLCs (integrated into production control systems), or industrial computers (used for data recording and analysis).

3、 Key technical characteristics: Core parameters that determine measurement accuracy and reliability

The performance of the material tank weighing sensor directly affects the accuracy of production control, and its key technical indicators include:

　　Range (Capacity)The maximum load that the sensor can withstand (such as 0-5t, 0-50t) needs to be selected based on the maximum filling weight of the material tank (usually 70%~80% of the full range, with a safety margin reserved).

　　AccuracyUsually:Comprehensive error (% FS, percentage of full scale)The accuracy of industrial grade sensors is 0.1% to 0.5% (high-precision scenarios such as pharmaceuticals/food ingredients require 0.05% to 0.1%), which determines the credibility of weight data.

　　SensitivityThe change in output signal corresponding to the change in unit load (such as 2mV/V, which means that for every doubling of the excitation voltage, the output signal increases by 2mV/full-scale) affects the detection capability of small weight changes.

　　temperature characteristicThe working temperature range (usually -20 ℃~+60 ℃ or -40 ℃~+80 ℃) and temperature drift (such as ± 0.01% FS/℃) require temperature compensation circuits to correct the effect of ambient temperature on the sensitivity of resistance strain gauges.

　　anti-interference capabilityIncluding resistance to lateral forces (avoiding errors caused by lateral loads through shear beam structures or limit devices), resistance to vibration (through shock absorbers or high-frequency filtering), and resistance to electromagnetic interference (through shielded cable and grounding design).

　　long-term stabilityZero drift and range drift of sensors during long-term use (such as several years) (annual drift of high-quality sensors ≤ 0.05% FS), ensuring the reliability of long-term operation.

4、 Typical application scenario: Comprehensive coverage from ingredients to safety

The material tank weighing sensor runs through industrial productionFeeding Production Storage TransportationThe entire process, specific applications include:

　　1. Ingredients and Quantitative Control​

　　sceneAccurate ingredients for chemical raw materials (such as resins and catalysts), food additives (such as sugars and salts), and pharmaceutical raw materials (such as powdered active ingredients).

　　effectBy monitoring the weight of materials in the material tank in real-time and controlling the feeding speed (such as the start and stop of screw conveyors and pumps), we ensure the accurate proportion of ingredients in each batch of products (with an error of ≤± 0.5%), and avoid product quality defects caused by excessive or insufficient amounts (such as chemical reactions and poor food taste).

　　2. Inventory Management and Logistics Scheduling​

　　sceneStorage management of bulk materials such as cement, coal, and grain.

　　effectThrough the networking of multiple tank sensors (such as PLC system summarizing the weight of each tank), real-time calculation of the total inventory (such as "50 tons of cement tank 1 currently remaining, expected to be available for 2 days") is carried out to guide procurement planning and transportation scheduling (to avoid material shortage or backlog).

　　3. Reactor and process monitoring​

　　sceneFeed control of reaction vessels in petrochemical and fine chemical industries.

　　effectReal time monitoring of the amount of reactants (such as liquid raw materials and catalysts) added to ensure that reaction conditions (such as molar ratios and concentrations) meet process requirements and prevent safety accidents (such as explosions and excessive by-products) caused by feeding errors.

　　4. Security protection and over limit alarm​

　　sceneWeight monitoring of flammable and explosive (such as liquefied gas storage tanks), toxic and harmful (such as chemical intermediates) material tanks.

　　effectSet a weight threshold (such as triggering an audible and visual alarm when the weight corresponding to the liquid level exceeds 90% of the full range) to avoid the risk of leakage caused by overloading; Simultaneously monitor the empty tank status (to prevent pump damage from idling).

5、 Development Trend: The Future Direction of Intelligence and Integration

　　Digitalization and Internet of Things (IoT) integrationThe sensor is equipped with a built-in wireless communication module (such as LoRa, NB IoT), which directly uploads weight data to the cloud platform for remote monitoring and data analysis (such as predicting the remaining life of the material tank and optimizing the supply chain).

　　Multi parameter fusionCombined with temperature, pressure, and liquid level sensors, comprehensively judge the material status (such as "abnormal weight decrease+temperature increase" may indicate leakage).

　　High precision and miniaturizationDevelop miniature weighing sensors with smaller range (such as 0-1kg) and higher accuracy (± 0.01%) for laboratory or precision pharmaceutical scenarios.

summary

The weighing sensor of the material tank passes throughPower electric conversionThe core principle of converting the weight of materials in the material tank into quantifiable and transportable electrical signals is achieved in industrial productionPrecise control, safety monitoring, and efficient managementThe key equipment. Its technological development has always revolved aroundHigher precision, stronger anti-interference ability, and more intelligent interconnectionIn the future, it will further integrate into the Industry 4.0 system and become the basic perception unit for intelligent manufacturing and digital factories.