CN204299629U - A kind of unit style unit utilizes adjacent vapour to start intermediate pressure cylinder device - Google Patents

Abstract

The utility model discloses a medium-pressure cylinder device for starting a unit system unit by using adjacent steam, including a local machine and an adjacent machine. The local machine is provided with an auxiliary steam header of the machine, and the auxiliary steam header of the local machine is connected with a boiler reheater. The boiler reheater is connected to the medium-pressure cylinder of the steam turbine, and the auxiliary steam header of the adjacent machine is installed on the adjacent machine, and the auxiliary steam header of the adjacent machine is connected with the auxiliary steam header of the local machine through pipes. The utility model sends the gas source of the adjacent machine from the auxiliary steam header of the adjacent machine to the auxiliary steam header of the local machine through the pipeline, and starts the medium-pressure cylinder of the local machine. Use electricity and fuel oil to complete the quality inspection after the steam turbine overhaul, drive the rotor to rotate and do on-site work, and can run ahead of time, check the installation quality and conduct no-load test of the electrical part before the unit is connected to the grid, reducing the operation and maintenance during this period The workload can be reduced, and the uncoordinated maintenance schedule of boilers and steam turbines can be alleviated, so as to achieve energy saving, consumption reduction, high unit economy, reliability, and high utilization rate.

Description

A unit system unit uses adjacent steam to start the medium-pressure cylinder device

technical field

The utility model relates to a unit system unit with energy saving, consumption reduction, economy, reliability and high utilization rate, which utilizes adjacent steam to start a medium-pressure cylinder device.

Background technique

For a long time, during the maintenance of large-scale unit units, it has often occurred that the maintenance schedule of the boiler and the steam turbine cannot be well coordinated. It is often because the steam turbine needs to be inspected and repaired urgently after the maintenance is completed, or the on-site work (such as dynamic balance, etc.) is required to drive the rotor to rotate. ) and the boiler fails to ignite for some reason. However, when the boiler was overhauled and then ignited and the steam turbine was started, it was found that the overhaul effect of the steam turbine was not good and required rework, which delayed the construction period. The overhaul period of the unit is extended, and the reliability, utilization rate and economy of the equipment are reduced. In the design of large-scale thermal power plant unit units, adjacent units cannot be switched to each other. When the main equipment in a unit fails to operate, the entire unit can only be shut down. Poor operational flexibility is the main reason for the uncoordinated maintenance schedule of steam turbine boilers.

Judging from the implementation of the unit, from the ignition of the boiler to the end of the electrical test, it takes about 60 hours, consumes about 300 tons of fuel oil, and costs 2.4 million yuan per unit; at the same time, the boiler starts the fan, the steam turbine starts the electric water pump, and the unit starts The power consumption of the factory: (6300+3000+1700)*60=660000kw.h/unit, the consumption cost is 330,000 yuan/unit, and the total consumption cost is 2.73 million yuan/unit, which is expensive.

Contents of the invention

The technical problem to be solved by the utility model is: to provide a unit system unit that uses the adjacent steam to start the medium pressure cylinder device, which can realize the non-starting and non-ignition of the boiler fan, and the steam turbine side does not need to start the electric feed water pump to realize the medium pressure of the steam turbine. Cylinder startup, completion of quality inspection after steam turbine overhaul, on-site work on driving rotor rotation (such as dynamic balance, etc.), and no-load test of electrical parts before unit grid connection, in order to overcome the problems existing in the existing technology.

The technical solution adopted by the utility model is: a unit unit unit utilizes the adjacent steam to start the medium-pressure cylinder device, including the local machine and the adjacent machine, the local machine is provided with the local auxiliary steam header, and the local auxiliary steam The header is connected to the boiler reheater, and the boiler reheater is connected to the medium-pressure cylinder of the steam turbine. The auxiliary steam header of the adjacent machine is installed on the adjacent machine, which is connected to the reheating and cold section pipe of the adjacent machine. The auxiliary steam header of the adjacent machine It is connected with the auxiliary steam header of the machine through the pipeline.

A valve is arranged on the pipeline, which can connect and cut off the gas source, and can adjust the pressure of the steam flowing through, and play the role of safety protection.

The valve adopts an electric regulating valve, which is convenient for automatic control, reduces labor intensity and is precise in control.

The pipeline adopts a pressure pipeline with an outer diameter of 377mm and a wall thickness of 16mm, which can meet the punching pressure requirements of the medium-pressure cylinder of the machine, and is convenient for welding and installation.

Beneficial effects of the utility model: Compared with the prior art, the utility model uses pipes to connect the auxiliary steam header of the local machine with the auxiliary steam header of the adjacent machine, and transport the steam source of the adjacent machine to the machine to start the medium pressure cylinder , the boiler of this machine does not need to start the fan and ignition, and the steam turbine does not need to start the electric feed pump, which can save power and fuel in the plant, complete the quality inspection after the steam turbine overhaul, drive the rotor to rotate on-site work (such as dynamic balance, etc.), and can advance It can also reduce the workload of operation and maintenance during this period, and also alleviate the contradiction of uncoordinated maintenance schedules of boilers and steam turbines. At the same time, it has the advantages of Energy saving, consumption reduction, high unit economy and reliability, and high energy utilization rate. The cost of pipeline connection is 30,000 yuan/unit, which is very high compared to the cost of 2.73 million yuan/unit for direct startup of the machine. economic utility.

Description of drawings

Fig. 1 is a structural representation of the utility model.

In the figure, 1-adjacent machine auxiliary steam header, 2-pipeline, 3-valve, 4-local machine auxiliary steam header, 5-boiler reheater, 6-local machine medium pressure cylinder, 7-condenser, 8-neighboring machine reheating cold section pipe, 9-local machine reheating cold section pipe.

Detailed ways

As shown in Figure 1, a unitary unit uses the adjacent steam to start the medium-pressure cylinder device, including the local machine and the adjacent machine. The local machine is provided with the local auxiliary steam header 4, and the local auxiliary steam header 4 is connected to the boiler reheater 5, the boiler reheater 5 is connected to the medium pressure cylinder 6 of the steam turbine, and the auxiliary steam header 1 of the adjacent machine is arranged on the adjacent machine, which is connected to the reheating and cold section pipe 8 of the adjacent machine, and the adjacent machine The auxiliary steam header 1 is connected with the auxiliary steam header 4 of the local machine through the pipeline 2, and the auxiliary steam header of the local machine is connected with the auxiliary steam header of the adjacent machine by the pipeline, and the valve on the corresponding main engine system is closed, and the auxiliary steam header of the adjacent machine is sequentially connected. The reheating and cooling section, the auxiliary steam header of the adjacent machine, the auxiliary steam header of the main engine, the reheating and cold section of the main engine, the reheater of the main engine furnace and the medium pressure cylinder of the main engine form a closed steam source channel, and the steam source of the adjacent machine is transported to the local machine. The medium-pressure cylinder is started, and finally discharged from the condenser 7 connected to the medium-pressure cylinder, so as to realize the punching of the stamping cylinder. The boiler of this machine does not need to start the fan and ignition, and the steam turbine does not need to start the electric water pump, which can save electricity and fuel for the plant. , to complete the quality inspection after the overhaul of the steam turbine, to drive the rotor to rotate on-site (such as dynamic balance, etc.), and to run ahead of time, check the installation quality, and conduct the no-load test of the electrical part before the unit is connected to the grid. At the same time, it can also reduce this The workload of operation and maintenance during the period can also alleviate the contradiction of uncoordinated boiler and steam turbine maintenance period. At the same time, it has the advantages of energy saving, consumption reduction, high economy and reliability of the unit, and high energy utilization rate. The cost is 30,000 per unit, compared with 2.73 million per unit for direct start-up of this machine, it has a very high economic utility.

The pipeline 2 is provided with a valve 3, which can connect and cut off the gas source, and can adjust the pressure of the steam flowing through, and play a role of safety protection.

The valve 3 adopts an electric regulating valve, which is a hydraulically operated valve with a solenoid valve as the guide valve. The control response is accurate and fast, and the pipeline system is opened and closed remotely according to the electric signal to realize remote operation, and can replace gate valves and butterfly valves. For large electric operating systems. The closing speed of the valve is adjustable, and it closes smoothly without pressure fluctuations. The valve is small in size, light in weight, easy to maintain, easy to use, safe and reliable, easy to automatically control, reduces labor intensity, and has precise control.

The pipe 2 is a pressure pipe with an outer diameter of 377 mm and a wall thickness of 16 mm, which is the same size as the pipe outer diameter of the existing equipment, can meet the punching pressure requirements of the medium-pressure cylinder of the machine, and is convenient for welding and installation.

As shown in Figure 1, for the convenience of description, it is assumed that the adjacent machine that provides the steam source is No.

A unit system unit uses adjacent steam to start the medium-pressure cylinder device, which includes two parts: the pipeline system transformation process and the on-site implementation process.

Example 1: A unit system unit uses adjacent steam to start the pipeline system of the medium-pressure cylinder device and implement the process of transformation:

(1) Remove the check gate spool from the reheating and cooling section of No. 1 unit to the auxiliary steam header of No. 1 unit;

(2) Remove the reheating and cooling section of No. 1 unit to the electric adjustment door of the auxiliary steam header of No. 1 unit, and use short pipes to short-circuit;

(3) Remove the reheating and cooling section of No. 2 unit to the electric adjustment door of the auxiliary steam header of No. 2 unit, and short-circuit it with a short pipe;

(4) Set the electric door switch of the reheating and cooling section of No. 2 unit to the auxiliary steam header of No. 2 unit as pulse electric for 5 seconds;

(5) All other original piping systems remain unchanged, the auxiliary steam header of No. 1 unit is connected with the auxiliary steam header of No. 2 unit by pipelines, and valves are set on the pipelines;

(6) The pipe diameter, wall thickness and material of the pipe selected in the above steps should be consistent with the original pipe, and the welding should be carried out according to the material requirements.

Embodiment 2: On-site implementation process of a unit system unit using adjacent steam to start the medium-pressure cylinder device:

(1) Inject water into the circulating water system of unit 1, open the connecting door of the circulation pump outlet of units 1 and 2 to 50%, use the circulation pump of unit 2 to supply circulating water to unit 1, and open the bypass door of the open water pump The hydrogen cooler, closed water cooler, and stator cooling water cooler of Unit 1 are filled with water and exhausted, and can be used for the pump interlock test of Unit 1 at the same time to restore standby;

(2) Inject water into the stator cooling water system of Unit 1, and start a cooling water pump;

(3) Condenser water replenishment to normal water level 800~1000mm;

(4) Condensate water system injects water and exhausts air;

(5) The isolation system forms the starting channel of the medium-pressure cylinder: (a) Close the manual door of the desuperheating water of the No. 1 unit and the reheater, and close the electric door of the high-side desuperheating water; (b) Close the high-side and superheater test of the No. 1 unit Blocking valve, high row check door; (c) Close the auxiliary steam header of No. 1 unit to the deaerator heating manual door, close the auxiliary steam header of No. From the header to the boiler bottom heating steam main door, close the No. 1 auxiliary steam header to the coal mill fire-fighting steam main door, close the No. 1 auxiliary steam header to the heating general steam The steam inlet manual door of the auxiliary steam header of No. 1 unit; (c) close the exhaust steam disc valve of the small machine and the exhaust steam desuperheating water valve of the small machine;

(6) Start a condensate pump to recirculate and supply water to the condensate jellyfish pipe at the same time;

(7) Start the vacuum pump to evacuate the condenser, and observe that the cooling water of the vacuum pump should be put into operation normally;

(8) After the vacuum of the condenser reaches 0.03~0.05MPa, use the auxiliary steam source of No. 2 unit to warm up the auxiliary steam header of No. 1 unit, the shaft seal steam system, and the cold section pipeline of No. 1 unit;

(9) After the shaft seal steam heating pipe is completed, the shaft seal steam of No. 1 unit is put into the shaft seal steam, and the shaft seal steam of the small machine is not input;

(10) The main engine unit reverses: (a) The start-up steam source of No. 1 unit is provided by the auxiliary steam source of No. 2 unit. The specific flow direction of the steam source flowing through the equipment is as follows: No. 2 unit reheating and cooling section - No. 2 unit auxiliary steam header - Auxiliary steam header of No. 1 unit—reheating and cooling section of No. 1 unit—reheater of No. 1 furnace—intermediate pressure cylinder of No. 1 unit; (b) Steam parameters during flushing: the pressure in front of the intermediary pressure combined steam valve is 0.6~0.8 MPa, temperature 240~260°C, load of No. 2 unit ≥ 450MW; (c) No. 1 unit low-side open to 10% before No. 1 unit reverses, use No. 2 unit to reheat and cool section to auxiliary steam header electric The door adjusts the pressure in front of the medium-pressure combined steam valve of No. 1 unit at 0.8~0.9MPa, and the safety door of the auxiliary steam header of No. 1 and No. 2 units should not operate; (d) Set the target speed to 200r/min after the unit of No. 1 unit hangs the gate , the rate of increase is 100r/min/min, and the reheating is carried out. After the No. 1 unit is reversing, pay attention to the cranking tripping situation, and use the low side adjustment to control the reheating steam pressure; (e) Depending on the reheating steam pressure of the No. 1 unit tends to Stable, after the steam drum water level of No. 2 unit is stable, set the target speed to 1500r/min, and the increase rate is 100r/min/min, continue to increase the speed, and gradually turn down the low side of No. After the machine is cooled, go to the electric door of the auxiliary steam header to control the reheat steam pressure of No. 1 unit at 0.8~0.9MPa; (f) After the unit speed of No. 1 unit rises to 1500r/min, warm up the machine for 60 minutes, measure the vibration of each bearing, and inspect the unit After the expansion difference, cylinder expansion, and cylinder wall temperature difference reach the specified range of equipment operation, continue to increase the speed; (g) The speed of No. 1 unit is increased to 3000r/min, and the vibration of each bearing is measured.

Claims (4)

1. A unit system unit uses the adjacent steam to start the medium-pressure cylinder device, including the local machine and the adjacent machine. The local machine is equipped with the local auxiliary steam header (4), and the local auxiliary steam header (4 ) is connected to the boiler reheater (5), the boiler reheater (5) is connected to the medium pressure cylinder (6) of the steam turbine, the adjacent machine is equipped with an auxiliary steam header (1) connected to the adjacent machine reheat On the cold section pipe (8), it is characterized in that: the auxiliary steam header (1) of the adjacent machine is connected with the auxiliary steam header (4) of the machine through the pipe (2). 2. A unit system unit according to claim 1, using adjacent steam to start the medium-pressure cylinder device, characterized in that: the pipeline (2) is provided with a valve (3). 3. A unit system unit according to claim 2, using adjacent steam to start the medium-pressure cylinder device, characterized in that: the valve (3) is an electric regulating valve. 4. A unitary unit unit using adjacent steam to start the medium-pressure cylinder device according to claim 1, characterized in that: the pipeline (2) adopts a pressure pipeline with an outer diameter of 377mm and a wall thickness of 16mm.