Does the concentricity of the main shaft have a decisive impact on leakage in double-end face sealings?
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Does the concentricity of the main shaft have an impact on double-end face seals? I’ve read online that the spindle runout should be less than 1 micron ； There are also reports of seeing foreign equipment with spindle runout of 20 to 30 microns, yet the mechanical seal was not problematic
The concentricity of the main shaft has no decisive impact on the leakage of double-end face seals. Because the sealing elastic element will automatically compensate.
Then I would like to ask what percentage of spring compression is appropriate for modular multi-spring machine seals?
The compression amount of the springs in modular multi-spring machine seals (double-face type) has been tested for leak prevention by the manufacturers; there is no need to adjust it during installation. In my workshop, there are over 30 double-face machine seals, and maintenance is very simple – once installed, as long as the gaskets or O-rings at the locking points are properly in place, there will be no leaks； Generally speaking, the compression amount of the spring should preferably not exceed 2/3
A deviation of less than 1 micron is an exaggeration; the standard is less than 5 microns. Generally, a deviation of up to 15 microns has little impact on sealing, but once it exceeds 15 microns, reliability can no longer be guaranteed
The end face runout of the high-speed pumping ring can affect sealing; if the rotational speed is too high, the spring cannot compensate adequately. You mentioned that the spindle runout of foreign equipment is 20 to 30 microns, but there’s no issue with the seal. I think the runout is quite high; since there’s no leakage, it’s possible that the quality of the seal is good