【Q&A Question 007】April 27, 2016
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This post was last edited by liuquan1100 on 2017-8-7 22:12. [Q&A Question 007] April 27, 2016: What is the purpose of the test setup for turbine emergency shutdown valves? The answer key will be available after responding; scoring is based on answering the key points. The quick-close valve remains in the open position for an extended period. To prevent issues such as sticking of the valve stem or incomplete closing, the valve is closed slightly through a test to assess its reliability.
The function of the turbine emergency shutdown valve testing device is to verify the reliability of the valve’s operation during unit operation.
The function of the testing device is to check whether the valve stem moves smoothly, without affecting the normal operation of the turbine. The testing device uses a two-position three-way valve to send pressure oil back to the test piston, pushing it to its end position where the distance is twice that of the original position. The piston and piston disc cause the valve stem to move in the direction of closing the valve. The actual test pressure can be read using a pressure gauge on site; by comparing this value with the specified pressure, it is possible to determine whether the valve stem is functioning properly. If salt deposits form on the valve stem or oil residue is present in the cylinder, this can be eliminated by repeating the tests several times.
The quick-shut valve is the main shut-off mechanism between the steam pipeline and the turbine; it enables the steam flow to the turbine to be stopped in the shortest possible time. This valve is particularly important in the event of a turbine failure, as it plays a key role in protecting the turbine unit
The function of the testing device is to check whether the valve stem moves smoothly, without affecting the normal operation of the turbine. Test its flexibility and whether it shuts down quickly when the unit receives a danger signal
Check whether the piston of the experimental quick-close valve is flexible； Prevent the quick-close valve piston from becoming rusted and stuck due to lack of use over time, thus avoiding issues in emergency situations
The quick-shut valve serves to protect the turbine, with the aim of testing its flexibility and whether it can shut down quickly when the unit receives a danger signal.
The quick-shut valve is the main shut-off mechanism between the steam pipeline and the turbine; it enables the steam flow to the turbine to be stopped in the shortest possible time. This valve is particularly important in the event of a turbine failure, as it plays a key role in protecting the turbine unit
To test the reliability of the quick-close valve’s function, the test oil from the hydraulic assembly flows through the oil port to the test piston, pushing it toward the bottom of the piston; this, in turn, causes the valve stem to move in the closing direction via the piston and piston disc.
Before starting up, test whether the quick-shut valve can open and close smoothly and whether it reaches its full travel distance, in order to prevent issues such as the main steam valve failing to open or the control valve getting stuck during normal operation.
The quick-shut valve is the main shut-off mechanism between the steam pipeline and the turbine; it enables the steam flow to the turbine to be interrupted in the shortest possible time. This valve is particularly important in the event of a turbine failure, as it serves to effectively protect the turbine unit. During normal operation, the quick-shut valve remains in its fully open position at all times. To prevent salt from forming around the valve stem as steam seeps through it, which could cause the stem to stick, or to avoid other issues that might prevent the valve from functioning properly and lead to the shutdown of the turbine, the quick-shut valve must be able to operate as required, especially during emergency shutdowns. Therefore, a test valve for the quick-shut valve is provided; during testing, this valve is used to move the quick-shut valve slightly, thereby ensuring its flexibility and enabling it to function properly during shutdowns.