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Why is a certain level of vacuum specified as a requirement in the conditions for starting a steam turbine? Before starting up, the turbine must be under a certain level of vacuum, typically around 60 kPa. If the vacuum level is too low, more fresh steam is required to rotate the rotor. The excessive waste steam being discharged into the condenser suddenly causes the pressure on the steam side of the condenser to rise significantly, which may result in a positive pressure on that side. This can damage the safety film used for venting air, and it also causes significant thermal shock to the cylinder and rotor. When using an impulse rotor, the vacuum level should not be too high. A high vacuum level not only prolongs the time required to establish vacuum, but also results in a lower heat release rate due to the smaller amount of steam passing through the turbine; this slows down the heating of the turbine and makes it difficult to stabilize its speed, thereby extending the startup time.
A certain level of vacuum is required before starting the turbine, typically around 0.06 MPa. If the vacuum level is too low, more fresh steam is needed to drive the rotor; meanwhile, an excessive amount of waste steam being discharged into the condenser causes the pressure on the steam side of the condenser to rise sharply. This can result in a positive pressure on that side, damaging the safety film used for venting air, and it also causes significant thermal shock to the cylinder and the rotor. When using an impulse rotor, the vacuum level should not be too high. A high vacuum level not only prolongs the time required to establish vacuum, but also results in a lower heat release rate due to the reduced amount of steam passing through the turbine; this slows down the heating of the turbine and makes it difficult to stabilize its speed, thereby extending the startup time.
Before starting the turbine, a certain level of vacuum is required, usually around 60 kPa. If the vacuum level is too low, more fresh steam is needed to drive the rotor; moreover, when an excessive amount of waste steam is suddenly discharged into the condenser, the pressure on the steam side of the condenser increases significantly in an instant. This can result in a positive pressure on that side, damaging the safety film used for venting air, and it can also cause significant thermal shock to the cylinder and the rotor.
A certain level of vacuum is required before starting the turbine, typically around 0.06 MPa. If the vacuum level is too low, more fresh steam is needed to drive the rotor; meanwhile, an excessive amount of waste steam being discharged into the condenser causes the pressure on the steam side of the condenser to rise sharply. This can result in a positive pressure on that side, damaging the safety film used for venting air, and it also causes significant thermal shock to the cylinder and the rotor. When using an impulse rotor, the vacuum level should not be too high. A high vacuum level not only prolongs the time required to establish vacuum, but also results in a lower heat release rate due to the reduced amount of steam passing through the turbine; this slows down the heating of the turbine and makes it difficult to stabilize its speed, thereby extending the startup time.
Before starting the turbine, a certain level of vacuum is required, usually around 60 kPa. If the vacuum level is too low, more fresh steam is needed to drive the rotor; moreover, when an excessive amount of waste steam is suddenly discharged into the condenser, the pressure on the steam side of the condenser increases significantly in an instant. This can result in a positive pressure on that side, damaging the safety film used for venting air, and it can also cause significant thermal shock to the cylinder and the rotor.
(1) A certain level of vacuum must be present before the turbine is started up, usually around 60 kPa. If the vacuum level is too low, more fresh steam is required to rotate the rotor; moreover, when an excessive amount of waste steam is suddenly discharged into the condenser, the pressure on the steam side of the condenser increases significantly in an instant, which may result in a positive pressure on that side. This can damage the safety film used for venting air, and it also causes significant thermal shock to the cylinder and the rotor. (2) When starting the rotor, the vacuum level should not be too high either. A high vacuum level not only prolongs the time required to establish vacuum but also reduces the amount of steam passing through the turbine, leading to a lower heat release rate. As a result, the turbine heats up slowly and its speed is difficult to stabilize, thereby extending the startup time
(1) A certain level of vacuum must be present before the turbine is started up, usually around 60 kPa. If the vacuum level is too low, more fresh steam is required to rotate the rotor; moreover, when an excessive amount of waste steam is suddenly discharged into the condenser, the pressure on the steam side of the condenser increases significantly in an instant, which may result in a positive pressure on that side. This can damage the safety film used for venting air, and it also causes significant thermal shock to the cylinder and the rotor. (2) When starting the rotor, the vacuum level should not be too high either. A high vacuum level not only prolongs the time required to establish vacuum but also reduces the amount of steam passing through the turbine, leading to a lower heat release rate. As a result, the turbine heats up slowly and its speed is difficult to stabilize, thereby extending the startup time
Before starting up, the turbine must be under a certain level of vacuum, typically around 60 kPa. If the vacuum level is too low, more fresh steam is required to rotate the rotor. The excessive waste steam being discharged into the condenser suddenly causes the pressure on the steam side of the condenser to rise significantly, which may result in a positive pressure on that side. This can damage the safety film used for venting air, and it also causes significant thermal shock to the cylinder and rotor. When using an impulse rotor, the vacuum level should not be too high. A high vacuum level not only prolongs the time required to establish vacuum, but also results in a lower heat release rate due to the smaller amount of steam passing through the turbine; this slows down the heating of the turbine and makes it difficult to stabilize its speed, thereby extending the startup time.
A certain level of vacuum is required before starting the turbine, typically around 0.06 MPa. If the vacuum level is too low, more fresh steam is needed to drive the rotor; meanwhile, an excessive amount of waste steam being discharged into the condenser causes the pressure on the steam side of the condenser to rise sharply. This can result in a positive pressure on that side, damaging the safety film used for venting air, and it also causes significant thermal shock to the cylinder and the rotor. When using an impulse rotor, the vacuum level should not be too high. A high vacuum level not only prolongs the time required to establish vacuum, but also results in a lower heat release rate due to the reduced amount of steam passing through the turbine; this slows down the heating of the turbine and makes it difficult to stabilize its speed, thereby extending the startup time.
Before starting up, the turbine must be under a certain level of vacuum, typically around 60 kPa. If the vacuum is too low, more fresh steam is required to rotate the rotor; moreover, when an excessive amount of waste steam is suddenly discharged into the condenser, the pressure on the steam side of the condenser increases significantly in an instant