Quick-shut component

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Hangzhou turbine quick-shut assembly: This assembly is used for local start-up and shutdown of the turbine, remote shutdown, online testing of the quick-shut valve, as well as the automatic engagement of the emergency shut-off throttle. The quick-shut assembly is suitable for turbines equipped with electro-hydraulic control systems, as well as turbines without emergency shutdown valves. A quick-shut-off assembly is a hydraulic unit that combines various control elements within a control system; it not only facilitates operation but also helps to organize and simplify the layout of hydraulic and electrical circuits. The structure and appearance of the quick-shut component are shown in Figures 1 and 2; Figure 2 illustrates its working principle. 1. Test valve 2. Body 3. Start-up oil directional control valve 4. Quick-shut oil directional control valve 5. Shutdown solenoid valve 6. Electro-hydraulic converter 7. Support 8. Shutdown solenoid valve 9. Manual shutdown valve. Side A – Operation side. Figure 1: The body (2) contains internal oil circuits corresponding to those shown in the schematic diagram, and hydraulic components such as cartridge valves (DG16, DG40 in Figure 2) are installed therein. On different sides of the body, operating elements necessary for the quick-shut function are mounted, along with external pipeline connections; the positions of these operating elements and the locations of the oil circuit connections are all marked in accordance with the schematic diagram. The body is connected to the support (7) fixed on the foundation by bolts. The return oil from the quick-shut components flows into the return oil pipe through the return oil port of the body. The start oil directional valve, with tag number 1843, and the quick-shut oil directional valve, with tag number 1842, are both knob-type directional valves used to activate the quick-shut valve on-site. At startup, turn the knobs for 1842 and 1843 counterclockwise (as viewed from above) by 90°. This establishes a connection between P and B for 1842, as well as between A and T. Under the pressure of oil E1, the plug valve Dg16 closes, thereby cutting off the connection between E1 and E2; the pressure in E2 becomes 0. At the same time, a connection is established between P and B for 1843, as well as between A and T. As a result, pressure is generated by the start-up oil F and the control oil M. (If M is connected to the emergency shutdown throttle, the rapid shutdown mechanism has an automatic throttle engagement function; if M is not used, the emergency shutdown throttle must be manually engaged and reset on site.) Once the pressure of the start-up oil reaches ≥0.6 Mpa, the knob for 1842 should be turned clockwise by 90° to reset the rapid shutdown valve, thereby re-establishing connections between P-A and B-T. This causes DG16 to open, allowing communication between E1 and E2, and thus pressure is generated in the rapid shutdown oil E2. Once the pressure in E2 stabilizes, 1843 is reset (the knob is turned 90° counterclockwise, thereby establishing a connection between F and T). Since the return port of 1843 is equipped with a throttle orifice plate and an adjustable needle valve (located at the upper left side of the operating side A), the rapid shutdown valve gradually opens as the start-up oil flows back slowly. Figure 2: The addresses of the shutdown solenoids (5, 8) are 2222 and 2223 respectively; they are used for remotely shutting down the turbine. The solenoid valve shown in Figure 2 is in a de-energized state; during startup and normal operation, the pressure oil in 2222 and 2223 allows flow, while the DG40 cartridge valve closes under the action of the pressure oil. When either 2222 or 2223 is powered, the upper chamber of DG40 is connected to the return oil, causing DG40 to open. The quick-shut oil is then rapidly discharged, which leads to the closure of the quick-shut valve and the shutdown of the turbine. Depending on the user’s requirements, solenoid valves can be equipped with NO type (normally open, not energized during normal operation) or NC type (normally closed, energized during normal operation); explosion-proof solenoid valves are also an option. The electro-hydraulic converter (6) is not a functional component of the quick-shut-off assembly; it simply makes use of the oil circuit in its own body to be incorporated within the quick-shut-off assembly, and one or two such converters can be installed depending on the requirements of the unit. The manual shutdown valve (9) has the tag number 2250 and is used for local shutdown of the turbine. 2250: There is a red protective plate in front. To stop the machine manually, first flip the protective plate toward the operation side, then pull the handle; the result will be the same as when 2222(2223) is powered on, causing the turbine to stop. At various positions on the quick-shut assembly, there are 3 cover caps with chain links; these correspond to the interfaces shown in Figure 2, and pressure can be measured using the pressure gauge tool 5-7820-0001-99 that is provided separately, during startup or while the turbine is in operation. During operation, unscrew the cover cap, tighten the connector of the pressure measuring tool; the pressure at the measurement point can be obtained from the gauge on the pressure measuring tool. After taking the measurement, reverse the steps to restore everything to its original state. Hangzhou Turbine Co., Ltd. Page 2 of 3 When operating the quick-shut-off component, the following points must be noted: Before starting, it is necessary to confirm that the pressure oil P and the oil pressure in the upper chamber of DG40 are within normal ranges. . Before starting, verify that the state of the solenoid valve (powered or not) matches the requirements. . At startup, the reset sequence of reversing valves 1842 and 1843 cannot be reversed. Once the quick-close valve is opened, 1842 and 1843 cannot be operated any further. . After startup, the oil pressure of starting oil F should drop to 0. The installation location of the quick-shut component is shown in Layout Diagram 0-2015-T.Nr-00. The principle of the unit quick-shutdown component is shown in the control system diagram 0-0641-T.Nr-00. For the oil circuit connection of the quick-shut component, refer to the regulator oil circuit diagram 2-3911-T.Nr-00. Hangzhou Turbine Co., Ltd