How to solve the problem of the main shaft seal structure of the mixer?

Solve the problem of the sealing structure of the main shaft of the mixer?

1. Original sealing structure and problems

The original sealing structure of the main shaft bearing of the double-cone mixer is shown in. There are two seals, one is the labyrinth seal inside the casing to prevent the particles from leaking from the shaft and the casing; The second sealing is the sealing of the asbestos packing outside the cover.

In specific applications, because the particles entering the mixing box are subject to the vaporization effect of the high pressure air at the bottom of the mixing machine shell and the leaf mixing effect of the high-speed operation of the mixing shaft, the particles, like water, have great water permeability and mobility, and the micro-positive pressure natural environment of the mixing box body (some large dust removal equipment are air pressure natural environment), which makes the labyrinth seal difficult to work; However, the asbestos packing outside the casing is small in size and the clamping level of the screw cap is limited, so the actual sealing effect is also not ideal. The ash leakage occurs when the machine and equipment are not used for a week or even less than 24 hours. I have tried to immerse asbestos packing in oil or add engine oil, but the actual effect is not good. The asbestos packing is hard after being immersed in oil, and the ductility is lost. The actual effect of sealing is worse.

2. Rectification measures and actual effects

Improve the sealing structure of the main shaft bearing of the mixer. Remove the original sealing, and install a large specification (axial and radial) sealing box inside and outside the housing. The sealing box is fixed on the cover, and a round pin is placed on the inside and outside sides of the box. The inside and outside pins are wrapped with a number of ring felt strips along the axis rotation direction, and then they are clamped and sent into the sealing box. Later, according to the top screw outside the sealing box, the pin is pressed to close the felt, which has the effect of winding the shaft. In addition, the sealing property of asbestos packing with rotary cover is modified on both sides of the external sealing box to have further sealing effect.

The actual sealing effect of the modified structure is excellent, and the actual sealing effect can be repaired by properly tightening the top screw according to the actual sealing effect on time or in the whole process of application. After a certain period of application (generally more than half a year), when the adjusting range of the top screw is shorter, the felt strip and packing strip can be removed and replaced. Do not add all lubricating grease (grease) in the application of the felt strip and packing strip, and the operation cost is very low.