Domestic valve actuators have been applied in many fields
The valve industry plays an important role in the development of national economy as an important part of preparing manufacturing industry. Due to the fact that the domestic valve manufacturing level in China still has a certain gap compared with the international advanced level, many high parameters, high temperature and high pressure, and the key valve of the high pound are always dependent on imports.
In order to push the valve localization, in the state council issued the "several opinions about accelerate the development of the equipment manufacturing industry, the relevant state departments according to the requirements of the countries of major equipment localization, has made a series of major deployment, and led by national development and reform commission (NDRC), China machinery industry federation and China general machinery industry association, the deployment to formulate the relevant major equipment in the field of valve localization plan, and coordinate with related departments for many times, now the valve localization in the domestic valve industry has formed a consensus.
China valve association secretary-general Song Yinli said, at present the domestic valve actuator can basically meet the requirements of the operation condition of the thermal power unit safe and reliable operation, has the localization condition and ability.
The actuator is the main control device of valve, which is divided into electric actuator, pneumatic actuator, air-liquid linkage actuator and electro-hydraulic actuator. According to function division can be divided into switch type and regulation type two kinds. At present, the operating mechanism of supercritical thermal power unit in China is mainly imported. Single million kilowatts of super (super) criticality thermal power unit need to form a complete set of electric actuators are more than 600 sets, pneumatic actuators are more than 200, more than 20 gas-liquid linkage actuator, and a small amount of electro-hydraulic actuator.
The million kilowatts of super (super) criticality actuators according to the value calculation for thermal power unit localization rate is only about 15%, import actuator value accounts for about 85%, especially the external regulation localization rate of less than 10% of the actuator. Among them, the electric actuators such as boiler side (including desulfurization and denitration) and air gate are mainly imported products. A small number of non-critical valves in the side and part of the turbine are made of domestic electric actuators. Most pneumatic actuators adopt imported products; More than 16 mpa pressure temperature over 540 ℃, the key of the valve are all made of imported products.
The main reason for the user USES the import valve actuator: more than one, imported products for intelligent actuators, simple structure, movement and signal transmission speed, which can realize remote transmission, debugging and troubleshooting are relatively simple, shortcut, can realize the bidirectional transmission, PID adjustment, automatic calibration, calibration and diagnostics, amplifier and the actuator is an organic whole to integration module, control performance is good, relatively good control precision, but the supply cycle is long and expensive; The national production rate of the supercritical valve is very low, most of the key valves are imported, and the imported valves are almost all imported actuators.
As the super (super) criticality thermal power unit localization of efforts to promote and implement key valve, the valve localization rate increases, combined with pneumatic actuators generally adopt the way of valve factory homemade directly supporting, domestic will be increasing the proportion of the actuator.