High temperature solenoid valves are widely used in shipbuilding industry, testing equipment, heating equipment, hydraulic equipment and other fields, with working temperatures above 300 ℃ in thermal conductivity systems. Heating devices, industrial kilns, high-temperature soot blowing, drying equipment, steel mills, thermal power plants, textile printing and dyeing, petrochemicals, chemical equipment, HVAC, coating equipment, pharmaceutical machinery, electroplating and coating control systems, such as power plant exhaust pipe drainage system and exhaust steam system. In industrial production, automatic control of steam and heat transfer oil is not only necessary for the production process, but also a necessary condition for energy conservation. For many years, high-temperature solenoid valves such as steam and thermal oil have caused serious economic losses and hindered production due to such quality issues. Therefore, improvements and optimizations were made to the valves, and an analysis was conducted on how to apply and select them to meet the requirements of various production lines.
process control
In order to solve the reliability and maintainability issues of high-temperature and high-pressure solenoid valves, in addition to considering reasonable structure and suitable materials in the design, it is also necessary to control the production process of their key components during the manufacturing and testing processes. The key and special processes for processing high-temperature and high-pressure solenoid valves include surface treatment, welding, and precision machining.
1) The fine machining of nuts, valve plugs, and valve bodies is a key component of solenoid valves. The key points are the size of the inner hole of the screw cap, the outer ring of the valve plug, and the roughness of the sealing surface. Identify surface treatment of valve plugs as a critical process. Valve plugs have the characteristics of high hardness, high dimensional accuracy, and easy deformation, so it is necessary to screen the surface treatment of valve plugs. Conduct process capability analysis on key components to ensure the machining quality of the parts. Personnel, equipment, designated locations, regular inspections, data collection for statistical analysis.
2) The valve cover of the solenoid valve is welded to the magnetic insulation tube, and the magnetic insulation tube is welded to the fixed iron core. The original self fusion welding was changed to wire filling welding, which improved the welding strength and prevented fatigue cracking. Conduct compressive strength test and air tightness test after welding to ensure welding quality.
3) High temperature solenoid valves generally use hard seals for sealing. In order to ensure that the sealing performance meets the requirements, the sealing surface of the valve seat and the sealing of the valve core must be grounded. The sealing surface of the valve plug and valve seat adopts matching grinding technology to make the roughness of the sealing surface greater than 0.2 microns.
Production process control and maintenance of high-temperature solenoid valves
maintenance
When using high-temperature steam solenoid valve products, it is also necessary to pay attention to the installation and working environment conditions of the solenoid valve, such as temperature and pressure. The maintenance of steam solenoid valve products during normal use is also an important part to ensure their normal operation.
1) Please read the product manual carefully before installation and check if the installed product fully meets the usage requirements. Suggest that users send someone to be responsible for maintenance.
2) Before installation, the pipeline and accessories must be thoroughly cleaned to remove metal dust, residual raw material bands, rust and other impurities inside the pipeline. For unclean media, install a filter in front of the valve.
3) During installation, prevent condensation and impurities from depositing inside the valve. Do not install the valve at the lowest point of the pipeline to avoid affecting operation.
4) In order to ensure the normal use of the solenoid valve, multiple tests are required after installation before it can be officially used.
5) When working, pay attention to the working pressure of the front and rear valves. The maximum working pressure should not exceed the nominal pressure. The difference in the required minimum working pressure is that the difference in pipeline working pressure must be greater than the minimum pressure difference to prevent the solenoid valve from failing to operate. When the working pressure exceeds the rated pressure or maximum working pressure, the system should stop using or reduce the working pressure.
6) During normal valve maintenance, the dirt inside the valve should be cleaned regularly. For example, between the mating surfaces of the screw cap and valve plug, and between the static core and the dynamic core, be careful not to damage the sealing surfaces.
7) When the medium of the high-temperature solenoid valve is thermal oil, when removing it from the pipeline, the valve internals should be cleaned with CCL4 and compressed air should be blown clean for storage. When disassembling and cleaning, all components should be arranged neatly and restored to their original state.
8) The high-temperature solenoid valve should be cleaned of condensed water and gas first, and then tried several times until it operates normally before being put into use. When the electromagnetic valve for thermal oil is not in use for a long time, the manual valve should be closed at the same time.
Conduct research, analysis, and improvement through design, manufacturing, and maintenance. Effectively solved the problem of insensitive operation, jamming, and closing of high-temperature solenoid valves. The clever design and treatment between the valve core and the guide rail improve the smoothness effect, reduce wear, extend service life, adapt to medium temperature changes and frequent work. Enable valves to have higher reliability and safety throughout the entire system.
