Steam is widely used in industrial production, and in many situations, automatic control of steam is necessary to meet the requirements of production processes. With the deepening of energy-saving work, how to use reliable and inexpensive devices to effectively and accurately control steam has become a widely concerned issue.
Automatic control systems consist of three parts: sensors, controllers, and actuators. The most common problem encountered in practical work is the actuator. Electromagnetic valves are widely used in actuators due to their simple structure, low cost, and easy maintenance. However, due to quality issues with the steam solenoid valve, it often burns out the coil, leaks inside and outside, gets stuck, fails to open and close, and the entire automatic control device loses its effectiveness shortly after installation. This seriously affects production.
The reason for the quality problem of the solenoid valve is:
1. The saturated steam temperature at a high temperature and pressure of 6kgf/cm2 is 163 ℃, and when the pressure is 16kgf/cm2, the temperature exceeds 200 ℃. Due to the high temperature fluid passing through the center of the solenoid valve coil and the temperature rise generated by the coil after power on, if no special measures are taken, the coil will be burned out.
2. When corroded by high-temperature steam, the corrosion of the parts in contact with it is stronger than in oil, air, and water, which is why some solenoid valves get stuck and fail shortly after use.
3. During peak steam usage, the pressure fluctuates greatly and the steam pressure is very low; And during low steam usage, the pressure is also very high, which is also the reason for some solenoid valve opening and closing failures. Especially for indirect solenoid valves, the wear of the main valve cannot be compensated for, and after a period of use, it often cannot be opened at low pressure.
4. Previously, the range of medium viscosity applicable to solenoid valves for condensate water was very narrow. Electromagnetic valves used for gases cannot be used for liquids, and electromagnetic valves used for liquids cannot be used for gases. When steam is transported in pipelines, there are different amounts of condensed water due to changes in external temperature, often causing the solenoid valve to malfunction.
Only by solving the above problems can the steam solenoid valve meet the minimum requirements for use. I have been researching steam solenoid valves since 1975. We have taken the following measures to solve the above problems.
1. We use special high-temperature electric heating materials and sealing materials, and adopt special processing technology to achieve a temperature resistance of up to 220 ℃.
2. The valve body is made of aluminum alloy, and the other parts in contact with the medium are made of stainless steel, which solves the problem of corrosion.
3. Adopting a distributed direct structure, the pressure adaptation range is 0-16kgf/cm2, the action is reliable, and the service life is not shortened due to wear and tear.
4. Special design and inspection measures have been adopted to expand the applicable range of medium viscosity, ensuring that the condensate water contained in the steam pipeline will not hinder the operation of the solenoid valve during normal use.
5. By eliminating the traditional reset spring and utilizing fluid lubrication, the performance of fatigue and wear resistance has been improved.
After more than seven years of practice, the feasibility of this plan has been confirmed. ZQDF-3 series steam solenoid valve. Reliable operation and long service life during on-site use.
