1. Overview
In the event of an emergency in the hydro-generator unit, when the unit is shut down in an emergency, if the turbine governor fails and the guide vane follower cannot be closed in time to cut off the water flow, the speed of the hydro-generator unit may rise to the runaway speed. In order to limit the overspeed of the unit and avoid runaway accidents, it is an important measure to protect the safety of the unit by setting up an overspeed limiting device and emergency closing the guide vane relay when the turbine governor fails. Especially in the hydropower station where the turbine water diversion system is not equipped with the turbine inlet valve or the quick gate, the setting of the overspeed limiting device is particularly important.
The CGF type overspeed limiting device accepts the electrical control signal of the power station monitoring system for operation; when the power station monitoring system fails or the control and operation power supply disappears, the overspeed limiting device can directly accept the hydraulic pressure of the motor reversing valve of the mechanical hydraulic overspeed protection device. control signal to operate. It can reliably realize the overspeed limit of the hydro-generator set.
The CGF type overspeed limiting device adopts a two-way cartridge hydraulic valve integrated control block structure in structure, and realizes the above functions through a well-designed hydraulic system, special electro-hydraulic reversing valve, two-way cartridge valve and valve block. The hydraulic system components of the device are integrated on a valve block, which is very convenient for installation, debugging and maintenance.
2. Technical parameters
Rated pressure: 16MPa
Nominal diameter: DN32, DN50, DN80, DN100
Power supply voltage: 220VDC, 20VAC
Pressure switch pressure setting range: 5～200bar
Pressure switch contact capacity: 0.2A/250VDC 3A/AC220V
Ambient temperature: 5～40℃
Relative humidity: ≤95%RH
3. Dimensions
