Application of Pulling Rope Displacement Sensor in Power Plant
Application of Pulling Rope Displacement Sensor in Power Plant
With the characteristics of dust resistance, vibration resistance, simple installation and wide measuring range, the pull rope displacement sensor is widely used in valve opening, equipment displacement and safety monitoring in thermal power plants and hydropower plants, providing reliable data for the stable operation of the unit.
In the hydropower plant, it is mainly used for real-time monitoring of the opening of intake gate, tailrace gate and surge tank valve, cooperating with the control system to realize automatic opening and closing and limit protection. At the same time, it can monitor the small displacement of dam slope and powerhouse structure and warn the deformation risk in advance. In thermal power plants, it is mostly used to detect the stroke of baffle doors, plug-in valves and ash discharge valves of boilers and desulfurization and denitrification systems, accurately feedback the position of air door switches, and ensure the stability of air volume and flue gas ratio; It is also used to control the material level of coal bunker and the displacement of unloading trolley, and is suitable for the harsh working conditions of high temperature and dust. In addition, it is also used in steam turbine speed regulating mechanism, hydraulic cylinder stroke, lifting equipment positioning and other scenes. The non-contact structure is stable and durable, effectively reducing downtime and maintenance, and improving the automation and safe operation level of power plants.
A typical application case of cable displacement sensor in power plant
1. Monitoring of dam/intake gate opening
Pull-rope sensors are installed in the working gate, emergency gate and tailrace gate of the water intake of hydropower station to detect the opening height of the gate in real time, and output 4 ~ 20ma signals to connect to PLC, so as to realize automatic control and up-down limit protection of the gate, instead of the traditional mechanical limit switch, with higher accuracy and more stable operation.
2. Displacement detection of surge shaft/spillway radial gate
It is used to measure the stroke of radial gate and flap gate, and accurately feedback the gate angle and opening during reservoir water level regulation and flood discharge in flood season, so as to ensure the stability of the pressure regulating system of power station and prevent the water level from fluctuating violently.
3. Positioning of air door and baffle door in thermal power plant
Boiler air supply damper, air guide baffle and flue gas baffle of desulfurization and denitrification system are used to detect the switch angle and stroke, so as to realize accurate ratio of air volume and flue gas volume, improve combustion efficiency and environmental protection emission compliance rate.
4. Displacement control of coal bunker unloading trolley and coal feeder
In the coal conveying system of thermal power plant, the pull rope sensor is used to locate the unloading trolley and monitor the stroke of the scraper coal feeder, which can still work reliably in the environment of heavy dust and strong vibration to avoid the collision between the coal pile and the equipment.
5. Hydraulic hoist cylinder stroke monitoring
All kinds of hydraulic drive gates, butterfly valves and ball valves are equipped with cylinders, and the pull rope sensor is installed to feedback the piston displacement in real time, so as to realize synchronous control and closed-loop adjustment of multiple cylinders and improve the opening and closing stability.
6. Displacement of auxiliary mechanism of steam turbine and water turbine
It is used for the feedback of governor actuator, main valve stroke and guide vane opening, providing high-precision position signals for speed adjustment and load control of the unit, and ensuring the safe grid connection and stable power generation of the unit.
7. Settlement/displacement monitoring of factory buildings and hydraulic structures Small displacement is monitored for a long time in key structures
such as power plant, retaining dam and slope, and deformation data is recorded by pull-string displacement meter, which provides a basis for structural safety assessment and disaster early warning.