Hydro Turbine Pressure Valve Maintenance And Inspection
Author: source: date: 2020-06-24 11:56:58
The gate visual inspection shall include the following:
1 Whether the gate is deformed, cracked, desoldered, rusted or damaged.
2 Whether the door slot is jammed or cavitation eroded.
3 Whether the opening indicator is clear and accurate.
4 Is the water stop facility intact and the structure of the lifting point solid?
5 Whether there are rust, cracks, bending and other phenomena in the tie rods and screws.
6 Are there any corrosion or broken wires on the steel wire rope or link chain?
The visual inspection of the hoist equipment should include the following:
1 Whether the hoist is flexible and reliable.
2 Whether the braking and limit equipment are accurate and effective.
3 Whether the power supply, transmission, lubrication and other systems are normal.
4 Whether the standby power supply and manual opening and closing are reliable.
The corrosion detection of gates and hoists should include the following:
1 Corrosion parts and their distribution, depth, size and density of corrosion pits (or corrosion holes).
2 The area of severe corrosion accounts for the surface area of the metal structure or component.
3 The erosion cross-sectional dimensions of metal components (including gate rails).
When there is any doubt about the material of the gate and hoisting equipment, a material review shall be carried out.
When the quality of the welding seam of the gate and the hoisting equipment is in doubt, non-destructive inspection of the welding seam shall be carried out.
When the working conditions of the gate and the hoisting equipment change, a review calculation should be carried out, and if necessary, a structural stress test can be carried out.
Gate opening and closing equipment should be tested for gate opening and closing force.
The safety level of gates and hoisting equipment shall be assessed in accordance with the provisions of Article B.2.1 of Appendix B of this code.
The main valve detection and evaluation objects should include: valve body, water filling valve (bypass valve), locking device, operating device, hydraulic device, etc.
The main valve inspection should include the following:
1 Main valve appearance and corrosion.
2 Main valve sealing.
3 Pipeline leakage.
4 The operation of the locking device.
5 Working condition of electro-hydraulic control device.
The on-site test of the main valve should be carried out selectively according to the on-site inspection and actual operation. The indicators of the inspection and evaluation items should comply with the current industry standards "Guidelines for Selection, Test and Acceptance of Hydraulic Turbine Inlet Hydraulic Butterfly Valves" DL/T 1068 and "Power Station Valve Electric Actuator" DL/T 641.
The appearance of the main valve should be good, anti-corrosion measures should be in place, no large-scale corrosion; the main valve should be closed tightly, there should be no jamming during the opening and closing process, there should be a locking device when the hydraulic main valve is fully closed, and the hydraulic device should work normally. There should be no leakage in each pressure pipeline and pressure oil tank, and no leakage in the hydraulic pressure relay cylinder; the expansion joint of the main valve should have a certain adjustment margin, and there should be no leakage at each connection; the main valve should be equipped with a balanced pressure device, beside The through valve should work well, and there should be no water leakage after the air valve is closed; the heavy hammer valve should not have repeated small switching actions after full opening; the pure manual valve switching operation should not fail, and the valve core should not have obvious leakage; the screw does not It should be bent and deformed; the electric and hydraulic control devices can work normally, and can be automatically and manually switched.