Correct operation method of constant temperature magnetic agitator in case of failure
Thermostatic magnetic agitator is mainly used for stirring or stirring liquid or solid-liquid mixture with low viscosity. Its basic principle is to use the magnetic field of the same repel, opposites attract principle, using magnetic field to push the magnetic agitator placed in the container for circular movement, so as to achieve the purpose of stirring liquid. With the heating temperature control system, it can heat and control the sample temperature according to the specific experimental requirements, maintain the temperature conditions required by the experimental conditions, and ensure that the liquid mixture meets the experimental requirements. When the constant temperature magnetic agitator is damaged in the experiment, we should not be anxious, but calm response, first judge the cause of failure, and then apply the appropriate medicine, will be able to get twice the result with half the effort, in addition, we should pay attention to the maintenance of electric agitator in daily use, as far as possible to extend the service life of the equipment.
1. Start work with mouth: in case of failure of electric agitator, do not start work in an emergency, but inquire about the process before and after the failure and the failure phenomenon. For unfamiliar equipment, should also be familiar with the circuit principle and structure characteristics, comply with the relevant rules. Before disassembly, it is necessary to fully understand the function, position, connection mode of each electrical component and the relationship with other surrounding devices. In the absence of assembly diagram, it is necessary to make sketches and mark them while disassembling.
2. External before internal: check whether the thermostatic magnetic stirrer has obvious cracks and defects, know its maintenance history and service life, etc., and then check the inside of the machine. Before disassembly, the surrounding fault factors should be eliminated and the disassembly can only be conducted after the internal fault is determined. Otherwise Several problems in practical application of heating magnetic agitator
Heating magnetic agitator has two major functions in the process of use: stirring function and heating function, among which:
1. Stirring function: drive the magnetic agitator through the * magnet located under the working disc. * magnet can penetrate the working disc surface, and the magnet is fixed directly on the rotating shaft of the motor. The actual speed of the instrument depends on the actual load and voltage. The fluctuation of voltage within the permissible range and the change of the viscosity of the treated medium will cause the fluctuation of the speed of the motor. The speed of the motor can be adjusted according to the requirements of the experiment.
2. Heating function: generally, heating magnetic agitator is equipped with heating device on the chassis. In addition, corresponding devices will be set to monitor the heating.
Analysis of several problems in the practical application of heating magnetic agitator:
1. What is stirring and mixing
1) reduce the system non-uniformity (phase, temperature, concentration, etc.) to achieve the required process results.
2) take heat transfer, mass transfer, reaction and product characteristics as the key goals.
2. To what extent is mixing enough? When will product quality and yield be reduced due to overmixing?
This problem depends on the product quality and selectivity of the stirring intensity and stirring time sensitivity. This requires a detailed understanding of these through experiments or simulations prior to process development and amplification.
3. What will result from poor mixing and mixing?
The successful production of products in line with the process objectives is crucial. If the product produced in the process of process amplification fails to reach the required productivity, quality and performance, then the production cost will increase significantly, and more importantly, when the investment of capital and time to improve the mixing and mixing effect, it may watch the market shrink. The cost of solving the mixing problem in the production process may be much greater than the cost of fully evaluating and solving the mixing problem in the process development process. The amount of money spent to improve mixing is enormous. In the United States, for example, the chemical industry loses about 5 percent of its value due to poor mixing and mixing. In 1989, the chemical industry alone lost billions of dollars. In 1993, a multinational chemical company also caused a loss of more than $100 million due to poor stirring effect.
, blind disassembly may lead to the worse repair of the equipment.
3, mechanical electrical: only in the determination of mechanical parts without fault, electrical inspection. When checking the circuit fault, the detection instrument should be used to find the fault location, and after confirming the fault without bad contact, the operation relationship between the circuit and the machine should be checked in a targeted way to avoid misjudgment.
4. First static state, then dynamic state: when the constant temperature magnetic agitator is not energized, the quality of the buttons, transformers, thermal relays and fuses of the electrical equipment can be judged to determine the fault location. Power test, listen to its sound, measure parameters, judge the fault, zui after maintenance. If the three-phase voltage value cannot be judged when the motor is out of phase, we should listen to it and measure each relative voltage separately to judge which phase is out of phase.
5. Cleaning before maintenance: for electrical equipment with heavy pollution, clean the buttons, wiring points and contact points to check whether the external control keys are out of order. Many faults are caused by dirt and conductive dust blocks.