Pneumatic circuit-breaking accelerator device for safety of steam turbine compressor unit
Technical Field
The utility model relates to a turbo compressor unit security device, especially a turbo compressor unit security throttle device that opens circuit.
Background
The press is provided with an exhaust pressure high (back pressure) protection shutdown function, generally overpressure power-off fast-closing protection. There are two forms of over-voltage power-off protection. One is to measure the pressure of the exhaust port through a sensor, judge through a controller, and cut off the power supply of the prime motor when the pressure exceeds a set pressure, so as to realize the shutdown; the other is to cut off the power supply of the prime motor to realize the stop through a pressure relay when the pressure exceeds the set pressure.
The original exhaust pressure high-protection shutdown technology realizes functions based on electrical elements and equipment, and the reliability of protection action needs to be ensured by depending on the reliability of the electrical elements and the electrical equipment. Therefore, it is necessary to design a pneumatic cut-off throttle to realize an exhaust overpressure protection shutdown function without depending on the reliability of electrical equipment.
Disclosure of Invention
The utility model discloses the technical problem that will solve is: the novel pneumatic circuit-breaking accelerator device for the safety protection of the steam turbine compressor unit is provided, and the exhaust overpressure protection shutdown function without depending on the reliability of electrical equipment can be realized.
In order to achieve the above purpose, the technical scheme of the utility model is that: a pneumatic open-circuit accelerator device for safety protection of a turbo compressor set comprises an accelerator shell, a hydraulic slide valve and a pneumatic piston, wherein the hydraulic slide valve is arranged in one side of the accelerator shell, the pneumatic piston is arranged in the other side of the accelerator shell, a gear and rack transmission mechanism is arranged in the middle of the accelerator shell, and a piston rod of the pneumatic piston is connected with a piston rod of the hydraulic slide valve through the gear and rack transmission mechanism; the inner cavity of the hydraulic slide valve is connected with a power oil inlet, and the outer cavity of the hydraulic slide valve is connected with a power oil outlet; an oil return port is arranged below the inner cavity of the hydraulic slide valve; and the upper cavity of the pneumatic piston is connected with an exhaust port of a compressor of a steam turbine compressor unit.
Further, the upper part of the accelerator shell is provided with a cover.
Further, the gear rack transmission mechanism is composed of a pneumatic piston rack, a hydraulic slide valve rack and a gear, the upper end of a piston rod of the pneumatic piston is fixedly connected with the pneumatic piston rack, the upper end of a piston rod of the hydraulic slide valve is fixedly connected with the hydraulic slide valve rack, and the pneumatic piston rack is in transmission connection with the hydraulic slide valve rack through the gear.
Further, the power oil inlet is connected with a high-pressure oil outlet of a steam turbine screw compressor unit; the power oil outlet is connected with a high-pressure oil inlet of a main valve of the steam turbine screw compressor unit; the oil return port is connected with an oil tank of the turbine screw compressor unit.
Further, when the exhaust pressure of the compressor exceeds the rated pressure, the upper cavity of the pneumatic piston enters compressed air led from an exhaust port of the compressor of the turbo compressor set, the pneumatic piston overcomes the spring force to move downwards and then drives the hydraulic slide valve to move downwards through the gear rack transmission mechanism, so that high-pressure oil led to the main valve is cut off and the main valve of the steam turbine is closed to stop emergently, and high-pressure oil below the hydraulic slide valve flows into an oil tank from an oil return port at the bottom.
The utility model has the advantages that:
the utility model discloses a pneumatic accelerator device that opens circuit compares original "overvoltage outage fast turn-off protection", has following characteristics:
1) the backpressure protection of the compressor is realized by the pure hydraulic, pneumatic and mechanical transmission principles;
2) the problem of back pressure protection function failure caused by the reliability problem of the electrical element can be avoided;
3) the problem of back pressure protection function failure caused by power failure can be avoided.
Drawings
FIG. 1 is a main sectional view of a pneumatic power cut-off accelerator apparatus for securing a turbo-compressor unit according to the present invention;
FIG. 2 is a cross-sectional view taken along A-A of FIG. 1;
fig. 3 is an application schematic diagram of the pneumatic open-circuit accelerator device of the present invention on a turbo-screw compressor unit.
Detailed Description
The present invention will be further explained with reference to the accompanying drawings and examples.
As shown in fig. 1 and 2, a pneumatic circuit-breaking accelerator device for security of a turbo compressor set comprises an accelerator housing 1, a rack-and-pinion transmission mechanism 2, a hydraulic slide valve 3, a pneumatic piston 4 and a cover 5. The upper part of the accelerator shell 1 is provided with a cover 5, one side of the accelerator shell 1 is internally provided with a hydraulic slide valve 3, the other side of the accelerator shell is internally provided with a pneumatic piston 4, the middle of the accelerator shell 1 is provided with a gear rack transmission mechanism 2, and a piston rod of the pneumatic piston 4 is connected with a piston rod of the hydraulic slide valve 3 through the gear rack transmission mechanism 2. The inner cavity of the hydraulic slide valve 3 is connected with a power oil inlet P, and the outer cavity is connected with a power oil outlet S. An oil return port Q is arranged below the inner cavity of the hydraulic slide valve 3. The upper chamber of the pneumatic piston 4 is connected with an exhaust port R of a compressor of a turbo compressor set. The power oil inlet is connected with a high-pressure oil outlet of the steam turbine screw compressor unit; the power oil outlet is connected with a high-pressure oil inlet of a main valve of the steam turbine screw compressor unit; the oil return port is connected with an oil tank of the turbine screw compressor unit.
The gear rack transmission mechanism 2 consists of a pneumatic piston rack, a hydraulic slide valve rack and a gear. The upper end of a piston rod of the pneumatic piston 4 is fixedly connected with a pneumatic piston rack, the upper end of a piston rod of the hydraulic slide valve 3 is fixedly connected with a hydraulic slide valve rack, and the pneumatic piston rack is in transmission connection with the hydraulic slide valve rack through a gear.
When the exhaust pressure of the compressor exceeds the rated pressure to a certain overpressure limit value for some reason, the compressed air from the exhaust port enters a chamber above a piston of the pneumatic cut-off throttle, the piston rapidly overcomes the spring force to move downwards, and then a gear and a rack drive a slide valve to move downwards, so that high-pressure oil leading to a main throttle is cut off, the main throttle of the steam turbine is closed to stop emergently, and high-pressure oil below the slide valve flows into an oil tank from an oil return port below the slide valve.
The utility model discloses a use of pneumatic throttle device that opens circuit on turbo wheel screw compressor unit (see figure 3).