Labyrinth seal device with adjustable seal clearance

Abstract

A labyrinth seal device with adjustable seal clearance comprises an annular comb tooth seat push-and-pull ring, wherein an annular outer ring is arranged on the outer side of the comb tooth seat push-and-pull ring, the left end side of the comb tooth seat push-and-pull ring is connected with an inner end of an annular left pull plate, the right end side of the comb tooth seat push-and-pull ring is connected with the inner end of an annular right pull plate, the left end side of the outer ring is connected with the outer end of the annular left pull plate, and the right end side of the outer ring is connected with the outer end of the annular right pull plate; an annular pressure working cavity is defined by the comb tooth seat push-and-pull ring, the left pull plate, the right pull plate and the outer ring; a plurality of comb tooth seats are arranged in an annular ring of the comb tooth seat push-and-pull ring in a surrounding manner, outer ends of the comb tooth seats are fixedly connected with the comb tooth seat push-and-pull ring, and the comb tooth seats can move in the radial direction under the action of the comb tooth seat push-and-pull ring. The labyrinth seal device with adjustable seal clearance is provided to effectively reduce leakage of a seal system, reduce energy waste of equipment in an operation process and prolong the service life of a labyrinth seal.

Description

Technical field [0001] The invention relates to a labyrinth sealing device with adjustable sealing gap. Background technique [0002] Labyrinth seal is also called comb seal, which is a non-contact seal. It is mainly used to seal gaseous media. It has a wide range of applications as interstage seals, shaft end seals and tip seals, or other dynamic seals in front of steam turbines, gas turbines, centrifugal compressors, blowers and other machines. The leakage of the labyrinth seal is proportional to the size of the throttle backlash. Considering the sealing performance, it is hoped that the throttle backlash should be as small as possible, because the increase of the leaking volume of the labyrinth seal will cause a lot of energy waste. However, if the throttle backlash is designed to be very small, for steam turbines, gas turbines and other equipment with long shafts, during the process of starting and stopping the rotation, the speed of the shaft needs to pass more than one cri...

AI Technical Summary

Problems solved by technology

The leakage of the labyrinth seal is proportional to the size of the throttling backlash. Considering the sealing performance, it is hoped that the throttling backlash should be as small as possible, because the increased leakage of the labyrinth seal will lead to a lot of energy waste

But if the throttling backlash is designed to be very small, for steam turbines, gas turbines and other equipment with long shafts, in the process of starting and stopping, the speed of the shaft needs to pass through more than one critical speed during the change process. Near the critical speed, the vibration of the rotating shaft will increase sharply, which will cause friction or even collision between the comb teeth and the rotating shaft, resulting in a larger throttling backlash, and may even cause the labyrinth seal to lose its sealing effect due to the breakage of the comb teeth

Therefore, for those equipment whose rotating shaft beats greatly during the process of starting and stopping the rotation, people have to design the throttling backlash of the labyrinth seal to be relatively large, which leads to a large waste of energy during the operation of the equipment.

Images