Bearing - Shaft

1) What's wrong with measuring an unworn area of the shaft before spraying?

2) Obtain a quotation plus datasheet from the bearing distributor.

0.005mm or 0.0002"

It is a ball bearing and the shaft should be sliding or light pressed. In the bearings catalogue (look at SKF) there is a chapter where for every bearing type the tolerances for the shaft or housing are listed.

Respect them and it will work properly.

starts from page 75 for deep groove ball bearing

check for yourself but a quick look says 110.03 mm shaft size for light interference fit

0.036 - 0.066 mm crush ( 0.066 for high axial loads or high axial combined with high radial load which your pump wouldnt have - high radial loads is what you get on a truck axle or bulldozer drive for example )

here

The shafty diameter after finishing should be 0.008 to 0.033 mm higher than the bearing ID. This is based on SKF recommendation.

You should approach this with some caution because of the amount of power the pump is absorbing. The large C3 clearances on the bearings suggest that it is not a difficult application but you need to look a bit at some of the other operating conditions...is this bearing the floating bearing? It probably is because of the double row 7200 series bearing at the other end. Is the outer bore or inner bore intended to be the floating side? Are you pumping liquids of constant density or can they vary? If so, the pump bearings will be seeing some differing loading conditions that warrant some consideration.

The simplest way to go through this checklist is with your bearing supplier's engineer to zero in on the shaft and bore fits that you will need for this application.

Jon.

actually Sawmilleng is correct , you need to consider if there is one floating bearing and if so then which one that is.

if the pump gets temperature fluctuations from the fluid medium , weather cycling , or heat transfer from the drive motor or coupling friction along the shaft then you might require one bearing with a floating tolerance

a floating tolerance might be H6 for example but check the original intended design of the assembly

It is basically recomened to have the ring fixed on the shaft and let the outer ring slide in the housing. H6 is a BORE tolerance and we speak about the shaft the tolerance field starts with a NON capital letter. If the field would be correct which is not it should be h6 !

The two 7222 at NDE should be for radial and thrust load whereas this 6222 at DE should be for pure radial load. Why shaft at DE bearing location worn-out in the first place? Even misalignment should lead to failure of the bearing and not the shaft. Has lack of lubrication, led the rolling element to seize up as a single block, thus made the shaft run inside the inner race? Repairing and fixing up the shaft, pump may not sustain if the primary/root cause is not addressed.

Metal spraying may bend the shaft if adequate care is not taken. Sleeve-ing is an alternate, with due consideration of not taking a deep cut.

yes mister yesyen

loss of seal integrity in a pump could bring contamination into the bearing

plasma welding will only add a few .000ths of an inch as i understand it. the shaft might need to be welded and reground to returned it to specs. consult the bearing company for the right fit.

before you go though the trouble of rebuilding the shaft, find the cause of the problem. a wrong or a siezed bearing for example. never buy chinese bearings. they are junk.