Turbine vacuum

And how is it destroyed? Is it a vacuum destroyer? What kind of operations and processes are involved?

The atmospheric safety valve is activated to break the vacuum; under normal conditions, the condenser condenses steam to maintain the vacuum, while the pump creates the vacuum

In condensing steam turbines, the exhaust pressure is reduced by creating a vacuum using an ejector, in order to make full use of the steam’s enthalpy drop and improve thermal efficiency. In the event of an emergency shutdown, the control valve that connects the vacuum system to the atmosphere is opened, thereby breaking the vacuum and causing the compressor to shut down as part of the interlock mechanism

Vacuum is created by a vacuum pump; the principle is similar to blowing bubbles into the mouth of a bottle when you were young, and in industrial applications steam is usually used.

The exhaust pressure of the condensing steam turbine is evacuated using an ejector; the absolute pressure at the tail end for low-vacuum heating is 30 kPa

Air seal. It is formed by a vacuum ejector, and the valve is broken by turning it on and off according to the operating procedures.

Steam seal: Purpose. A steam seal is a sealing device that prevents mechanical contact between the stationary cylinder and the rotating rotor; it is achieved by installing a sealing strip on the corresponding sealing surfaces of the shafts, or by creating comb-like sealing strips on the shaft surfaces. These continuous labyrinthine sealing strips serve as energy converters. The potential energy of the fluid is converted into kinetic energy, which is then dissipated within a series of sealed structures. In such a sealing device, the moving parts have no contact with the fixed parts, and a small amount of steam leakage is acceptable. The design of the mechanical seal involves splitting it axially into two parts, which are securely fixed to prevent rotation and to maintain a constant relative position between the upper and lower sections. The stainless steel sealing strip is fitted into the groove on the inner surface of the steam seal using a special tool with a square cross-section. Positive pressure steam seal: When a steam seal is used to seal the high-pressure gas inside the turbine casing, most of the leaking steam is consumed in the middle section of the comb-tooth seal. A small portion of the vapor that escapes from the freedom system leaks into the collection groove and is released into the atmosphere. On the axis of the groove collection section, there is a fin-like device that, under the action of centrifugal force, draws in the air at the end of the steam seal into the collection groove; this air is then discharged into the atmosphere along with the leaked steam. This is a very effective method for preventing sealed steam from leaking out of the steam seal and entering the adjacent bearing housing, thereby avoiding heating of the bearings. Negative pressure steam seal: A negative pressure steam seal is used to prevent pressurized fluid from leaking into the negative pressure area through the steam seal. Unlike positive-pressure steam seals, the structure of this type of seal is not designed to draw in leaking steam; instead, a slightly positive pressure of sealing steam is introduced into the seal. Sealed steam divides the steam seal into two parts. Part of it enters the cylinder of the turbine, while the other part leaks into the collection tank and is drawn out along with air by the extractor for condensation. Condensate drainage: Due to steam leakage and the condensation of sealing steam, condensate is formed within the steam seal structure; this condensate is effectively removed through the holes at the bottom of the steam seal structure.

These are all covered in the basic knowledge of steam turbines