What to do if the circulating water freezes in the intermediate frequency furnace in winter? Choice of antifreeze
In the winter, many intermediate frequency furnaces will face the problem of freezing the circulating water after the operation is stopped. Because the indoor and outdoor temperatures in the north are too low, the circulating water will freeze, which will cause the intermediate frequency furnace cooler to freeze and the pipes to freeze and affect normal production operations.
First, anti-freezing measures of intermediate frequency furnace in winter
1. Prevent the circulating water from freezing
If the on-site operation system is not a 24-hour continuous shift system, it is recommended to add antifreeze to the circulating water in the cooling tower coil. The antifreeze has a purity of more than 99% ethylene glycol. This antifreeze does not corrode the coil and itself. It does not volatilize, and the ratio of antifreeze to circulating water needs to be selected according to the site.
2, prevent the cooler from cracking
From the aspect of antifreeze in winter, the cooler coils of the intermediate frequency furnace cooling tower are inclined. This way, when the cooling tower is stopped in winter, the cooling water in the cooler coils of the cooling tower can be guaranteed to be exhausted, thereby preventing the cooler coils from freezing due to low temperature crack. An electric heater is installed in the spray water tank of each cooling tower, and the electric heater is started and stopped within the temperature range through temperature control, thereby ensuring that the spray pump pump body will not be frozen and cracked due to the low temperature freezing of the spray water .
3. Prevent pipeline freezing
The freezing of the pipeline can only be dissolved by external heat supply, and the freezing position is where the water in the pipeline is very low. The depressions are frozen, and all the pipes will be frozen. An electric water heater can be placed under the low-lying land and gradually dissolve. In order to avoid re-freezing, you only need to place a radiant plate or electric furnace under the ceramic dielectric capacitor. The power need not be too high to ensure that the water in the depression does not freeze. In order to prevent re-icing, it is recommended to install a foot valve in a very low standing water position and open the valve each time the device is closed in cold weather to dry up the standing water and then close the valve.
4. Winter antifreeze mode
For full production tasks, there is basically uninterrupted production, but there are short-term production breaks, you can switch to winter antifreeze mode, set the interval time and running time yourself, and the device can automatically run according to the set program. However, it should be noted that the working time should not be too long, and the power supply should be normal, so that the circulating medium in the system is sufficient.
II. Antifreeze type of intermediate frequency furnace
1, glycol antifreeze
Glycol is a colorless, slightly viscous liquid with a boiling point of 197.4 ° C and a freezing point of -11.5 ° C. It can be mixed with water in any proportion. Glycol antifreeze formulated with 40% glycol and 60% water (volume ratio) can be used at -20 ° C. If the temperature is around -40 ° C, then use 60% glycol and 40% water Ratio. After mixing, the freezing point is significantly reduced due to the change in the vapor pressure of the cooling water.
Ethylene glycol antifreeze is prone to generate acidic substances during use, which has a corrosive effect on metals. So add an appropriate amount of disodium hydrogen phosphate to prevent corrosion. In addition, at low temperatures, ethylene glycol has high viscosity, increased resistance, and the corresponding medium flow rate is reduced. It cannot be added too much, and it will easily overflow when the temperature rises.
2, alcohol glycerin antifreeze
Alcohol glycerin antifreeze is prepared at a mass ratio of 43% alcohol, 15% glycerol, and 42% water. It should be noted that the added water can only be pure water and distilled water, because if there are impurities in the water, they will react with the substances in the original antifreeze solution. Light will reduce the antifreeze effect, and heavy will make the liquid deteriorate. Corrosion damages the container.
Three, precautions for selection of antifreeze
1. According to the ambient temperature of the place of use, according to the antifreeze performance parameters, prepare an antifreeze suitable for the local meteorological characteristics.
2, The freezing point of antifreeze generally needs to be selected to drop by 10 ° C from the winter temperature of the residence.
3. Concentrated antifreeze needs to be mixed with water.
4. You don't need to mix water with the antifreeze that you buy immediately, but you need to choose the antifreeze with high reputation and big brand.
5, daily maintenance should pay attention to check the amount of antifreeze, if found insufficient, you should promptly add the same brand of antifreeze.
6. The antifreeze should be replaced according to the date requested by the manufacturer. Generally speaking, the antifreeze should be replaced every two years.
The above is the answer to how to freeze the circulating water in the intermediate frequency furnace in winter. After the intermediate frequency furnace is disabled in winter, the circulating water needs to be drained or the water is turned off after the power is turned off to reduce the internal heat of the equipment. The water inlet valve should be opened before.