How to choose ultrasonic cleaning machine?Date: 2022-09-05Number: 513
1. Power selection: the effect of ultrasonic cleaning does not necessarily have a positive correlation (power × cleaning time) , and sometimes with low power, it takes a long time to eliminate stains. Because the power reaches a certain value, sometimes the stains will be quickly removed. Great Power, cavitation intensity will be greatly increased, cleaning effect will be improved, at this time the more sophisticated parts also have corrosion, because of small loss, and cleaning cylinder bottom plate cavitation more serious, there is no difficulty in using organic solvents such as trichloroethene. However, it is easy to suffer from water-point corrosion when using water or water-soluble cleaning agents. If the surface of the vibrating plate has been scarred, high power underwater cavitation corrosion caused by more serious, so according to the actual application of the selection of ultrasonic power.
Frequency selection: ultrasonic cleaning frequency 28 khz to 120 khz in the middle, the use of water or water cleaning agent caused by the physical cleaning effect of cavitation is obviously beneficial to the low-frequency, generally around 28-40 khz. For small gaps, crevices, deep hole parts cleaning, with high frequency (usually 40 kHz above) good, even hundreds of kHz. When cleaning clock parts, use 400kHz. If the use of broadband FM cleaning, the actual effect is better.
3, the use of cleaning basket: in the cleaning of small parts, often used basket, because the mesh to cause ultrasonic attenuation, need special attention. When the frequency is 28 khz application of 10mm mesh is appropriate.
4. Selection of cleaning agent temperature: the suitable cleaning temperature of water cleaning agent is 40-60 ° C, especially in cold weather if the cleaning agent temperature is low cavitation effect is poor, the actual cleaning effect is poor. Therefore, a part of the cleaning equipment in the cleaning cylinder outside the heating wire to carry out temperature control, when the temperature increases cavitation easy to appear, so the cleaning effect is better. When the temperature continues to rise, the gas pressure in the bubble increases, resulting in the reduction of the impact sound pressure, reflecting the product effect of these two factors.
5. On the amount of cleaning agent and cleaning parts of the location of the determination: usually cleaning agent above the surface of the vibrator 100 mm above the appropriate. Because the single-frequency cleaning equipment by standing wave field, the seismic amplitude of the node is very small, the amplitude of the fluctuation of large lead to uneven cleaning.
6. Selection of ultrasonic cleaning process and cleaning agent: before purchasing a cleaning system, the following application studies should be conducted on the parts to be cleaned: establish the material composition, structure and quantity of the parts to be washed, further identification of the dirt to be removed, which is to determine the need to use what kind of washing method, distinguish the use of water-based cleaning agents best with organic solvents prerequisite. Only in this way can the appropriate cleaning system be given, the development of a reasonable cleaning process and its cleaning agent. Considering the influence of physical characteristics of cleaning agent on ultrasonic cleaning, the steam pressure, interfacial tension, viscosity and density should be the main factors. Temperature may affect a variety of factors, so it will also affect the efficiency of cavitation effect. All cleaning systems must use cleaning agents.
When choosing cleaning agents, the following three elements should be noted: 1. Cleaning efficiency: select effective cleaning organic solvents, be sure to do experiments. If ultrasound is introduced into the original cleaning process, the organic solvent used usually need not be changed. 2. Easy to use: the liquid should be safe and non-toxic, easy to use and durable; 3. Cost: the cost of using cheap cleaning solvents is not necessarily low.
The use of solvent must be considered in the cleaning efficiency, safety, a certain amount of solvent can be cleaned how much the high utilization of the workpiece and other factors.
Naturally, the selected cleaning solvent needs to achieve the actual effect of cleaning, and should be compatible with the product to be cleaned workpiece materials. Water is a common cleaning agent, so the system of using water-based solution is easy to operate, low cost and widely used. But do not know for some materials and their stains are not suitable for aqueous solutions, so there are many organic solvents can be selected.
Different cleaning system: water-based system: usually consists of an open slot in which the product workpiece is immersed. The complex system consists of a number of slots and is equipped with reciprocating filters, rinsing slots, drying slots and other accessories. Organic solvent system: most of the ultrasonic cleaning equipment, usually equipped with a continuous waste liquid recovery device. The process of oil removal by ultrasonic vapor phase is accomplished by an integrated multi-tank system formed by an organic solvent evaporation tank and an ultrasonic immersion tank. Oil, grease, wax, and other stains dissolved in organic solvents are removed by a combination of thermal organic solvent vapors and ultrasonic excitation. After a series of cleaning processes, the products and workpieces are hot, clean and dry.
8. Choice of cleaning parts: another standard of reference for ultrasonic cleaning is the design of the upper and lower parts of the cleaning parts, or the tooling where the cleaning parts are placed. When the cleaning part is in the ultrasonic cleaning tank, the bottom of the tank shall not be touched by either the cleaning part or the cleaning basket. The total cross-sectional area of the cleaning parts shall not exceed 70% of the cross-sectional area of the ultrasonic groove. Plastics and their non-rigid plastics absorb ultrasonic energy, so be careful when using these materials for tooling. The efficiency of a better ultrasonic cleaning system would not be greatly reduced by an unreasonable design of the tool basket or by an excessive weight of the workpiece contained in the product. Hooks, shelves and beakers can be used for suitable cleaning parts.