Working principle

Control the discharge screw or electric vibration machine based on the rate of material weight reduction in the weighing hopper to achieve the purpose of quantitative feeding, namely the weight loss scale When the material in the weighing hopper reaches the lower limit of weighing, the discharge screw machine fixes the discharge amount according to the current speed, and controls the material in the silo to quickly drop into the weighing hopper. When the loading reaches the upper limit of weighing, it stops loading. Rapid loading can shorten the feeding time, improve the accuracy and control precision of weighing.

product description

Weigh the complete feeding system (bin, feeder, and bulk material) through a static scale and control the discharge flow of bulk materials through a variable speed motor or electric shaker. The material is unloaded from the system (through a spiral, vibrating tube, or groove), and the "weight loss" measured per unit time (dv/dt) is compared with the required feeding amount (preset value). The difference between the actual (measured) flow rate and the expected (preset) flow rate will be corrected by a feeding controller, which can automatically adjust the feeding speed to maintain accurate feeding amount without process lag. When the weight measured in the silo reaches the low level of the silo (re feeding), the controller will control the feeding system to feed according to the volume, and then the silo will quickly reload (manually or automatically), and the weight loss controller will restart. In the batch weighing weight loss system, the design is similar to that of the continuous weight loss system, however, the accuracy of the final weight of the feeding (batch) cycle is higher than the actual feeding amount control. The controller provides a high feed signal to the variable speed drive to achieve fast feeding, and then switches to a low feed control signal for precise control at the end of the batch.

Technical Parameter

Technical indicators:

System measurement accuracy ≤ 0.5%

System ingredient accuracy ≤ 0.5%

The range of ingredient metering control is 0.01-300t/h

Scope of application: Continuous stabilized soil, concrete mixing plant, cement batching sintering quantitative control feeding, coal powder quantitative control feeding, and various concentrated slurry batching.

Product Introduction of Weight Loss Scale: Weight loss scale, also known as weight loss feeder, weight loss feeder, weight loss batching scale.

The weightlessness feeder consists of a hopper, feeders (single and double axis spiral feeders), weighing system, and regulator. During operation, the hopper, material, and feeder are continuously weighed together. After the material is sent out, measure the actual weight loss rate and compare it with the required weight loss rate (set value). Automatically correct deviations from the set point by adjusting the feeder rate. Thus, the material can be fed uniformly and accurately continuously.

Suitable range: granules, powders, calcium carbonate, talcum powder, resin film powder granules, flour, starch, etc

Powder scale: solves the problem of feeding measurement and feeding with poor fluidity;

Granular scale: solves any possible bridging problem

Characteristics and Applications

● Large conveying capacity, high-precision weight loss feeding

● Corresponding powder/particle feeding can be achieved by replacing accessories (optional)

The disassembly of the screw part is simple to assemble and easy to clean

● There are corresponding specifications for pressure resistant, explosion-proof, and wear-resistant lining plate accessories

Can be used as a front feeding device

● Applied to granules, powders, calcium carbonate, talc powder, resin film powder granules, flour, starch, etc

Non standard products can provide design

● Can provide air pressure balance and dust removal options

Professional and accurate weighing and batching enable users to improve product quality. The powerful production data statistics function of the batching control system provides a strong guarantee for the scientific management of user production.

Detailed introduction of supporting software for weightlessness scale:

(1) Characteristics:

Linear calibration can achieve automatic or manual single item calibration, and the calibration time for each item can be flexibly set.

★ The effective number of digits for flow display can be set according to on-site requirements

★ One system can manage up to 64 weightlessness scales (using a 10 slot industrial computer)

★ Unlimited number of formulas

★ The total target flow can be adjusted online

★ Each scale can store up to 10000 coefficients of materials (such as linear calibration values)

Additional optional accessories for weightlessness scale:

★ Network version: The system can be set to a remote slave state, under the direct command of the control personnel from the remote headquarters, allowing for quick and cost-effective debugging of more complex systems

This system can be used as a slave and input into the DCS in the main control room. Communication methods can be selected as RS232, RS485/422, network card (TCP/IP), CAN bus, and various other field buses. To be used as a slave in DCS, the customer needs to provide a communication protocol in advance.

★ Dual machine hot standby version: When the host fails, the slave automatically switches to control within 100ms. In addition to the basic functions of a weightlessness scale, the Changlu Industrial Control weightlessness scale control management system also has the following advantages:

★ Dual group PID control. One set is used for coarse adjustment to improve the response speed of the control system, and the other set is used for fine adjustment to improve the accuracy of the control system. Currently, there are no other similar instruments using this method. Based on the principle of PID regulation, we can easily understand that each set of PID parameters can only adapt to one operating condition. If there is only one set of PID parameters, the accuracy of the control system must be considered first. So when the target scalar changes significantly, this set of PID parameters will definitely cause the system to either stabilize for a long time or fluctuate for a long time. This situation may occur when the target quantity switches and changes significantly, or when the flow rate changes significantly due to sudden shortage or excess of materials. For example, in a stable soil control system, the target total flow rate is usually 500T/h, but at road bends, the total flow rate should be changed to 250T/h, which means the change in target value is 50%. If using dual group PID control, we can use coarse tuning PID to quickly adjust the system to around 90% of the target amount, and then use fine tuning PID to achieve high precision and stability. And a single set of PID regulation can only achieve one of the functions or a compromise between one or two.