Ultrahigh pressure cylinder

Abstract

The invention discloses an ultrahigh pressure cylinder, which comprises an internal cylinder and an external cylinder. The rear part of the internal cylinder is sealed with the external cylinder. A steam inlet pipe and a steam exhaust pipe are connected on the external cylinder. The steam inlet pipe passes through the external cylinder and extends into the internal cylinder. Steam enters the internal cylinder through the steam inlet pipe. The front end of the internal cylinder is of a sealed structure. A communication pipe is hermetically connected on the internal cylinder. The other end of the communication pipe is hermetically connected on a steam exhaust opening of the external cylinder. Steam in the internal cylinder is directly discharged to the steam exhaust pipe through the communication pipe. A sealed interlayer space is formed between the internal and external cylinders. A high pressure heater that conveys relatively stable steam to the interlayer space is connected on the external cylinder. When the ultrahigh pressure cylinder operates normally, the steam pressure in the internal cylinder, the steam pressure in the interlayer space and the atmospheric pressure outside the external cylinder decrease progressively. The ultrahigh pressure cylinder reduces the internal and external pressure difference of the external cylinder and maintains the reasonable wall thickness of the external cylinder when through-flow is not changed and steam exhaust pressure is increased so as to alleviate the difficulty in design and manufacturing. The ultrahigh pressure cylinder has strong practicality and high safety.

Description

technical field [0001] The invention relates to a steam turbine, in particular to an ultra-high pressure cylinder, which is suitable for a secondary reheating unit. Background technique [0002] From the existing generator sets in the world, the reheating methods are divided into two types: primary reheating and secondary reheating. Among them, the purpose of secondary reheating is to further improve the thermal efficiency of the unit and meet the final exhaust humidity requirements of the unit’s low-pressure cylinder. However, adopting the double reheating method will make the structure of the unit more complicated, which not only lies in the structural improvement of the boiler, but also adds an ultra-high pressure cylinder. [0003] see figure 1 : the existing ultra-high pressure cylinder is mainly composed of an inner cylinder and an outer cylinder, the rear portion of the inner cylinder is closed with the outer cylinder, the front end of the inner cylinder is an open ...

AI Technical Summary

Problems solved by technology

Excessive wall thickness of the outer cylinder will cause the temperature difference between the inner wall and the outer wall to increase during the start-up and shutdown of the unit, resulting in an increase in thermal stress and an increase in the deformation of the cylinder. Extreme conditions such as collision and grinding directly affect the safety of the unit

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