@Tmoose:
You are right in the light of the rotating outer being a tight fit and a loose fit for the stationary inner. Prior to the failure, the mechanics did it the other way around,i.e, they made the housing bore loose and the stationary inner tight...very tight indeed(m6 for the shaft).
The...
the pattern is not offset to one side of the raceway so i don't suspect excessice axial load.
i would say its showing signs of dents at ball pitch followed by flaking.
no, damage is not all around the race
no colour on balls.
sorry, other pictures did not turn out good.
And this is what I meant by having to bearing sleeves to support both float bearing and fixed bearing during mounting (see attached). this practice ensures that there is no relative movement between inner and outer race for both fixed end bearing and float end...
Picture of dents at ball pitch attached .
the bearings do not sit idle. it is a 6008 VV.
the only analytical assessment I did is to undertake a performance assessment of the bearing during operation: check whether equivalent load rating, equivalent static load rating, critical speed are all...
when u mount the float end bearing, you have to have a bearing sleeve supporting the inner and outer races of both the float end bearing and the fixed end bearing. failure to adopt this practice will cause relative movement of raceways. it doesnt take much to brinell a deep groove ball bearing...
Tmoose,
the rolls stop turning when the bearing fails. I have not been on the shop floor so I am not 100% sure what constituted the failure. I was called after and asked to come up with a reliability improvement technique.
9880501843,
This bearing is from a paper sheeter and it has been seleced from the OEM. When it fails, the sheeter goes offline and then our fitters oull the roll , dismount the bearing and fit new ones in.
it is a rotating outer ring with a stationary outer ring load. So the inner ring is a...
Hi all,
I have an NSK deep groove ball bearing designation num 6008.This has 12 ball elements. Can anyone point out another bearing manufacturer equivalent that has the same number of balls? or more!
Secondly: We have had numerous failure of this 6008 NSK and I suspect that it may be mounting...
Ok gents,
the opening thread was from a study done by a consulting company. I was given specs of the HX such as area, U, so I cannot confirm that it is a shell-tube or plate heat exchanger.i take it from the study that such a close approach must imply a plate HX.
What I then did is that I...
RS82,
changing the process fluid flow rate will change its exit temperatures.
the overall heat transfer coefficient is dependent on both the cooling water and process water flow rates since it is a function of the convection heat transfer on the shell side and tube side. Any heat transfer...
gents,
the objective here is to maintaing cooling water at lower than 25 deg C.There are alarm limits in the turbine controls in that inlet cooling water > 25 deg C will send operators in panic mode. So, it is a simple cooling issue as SNORGY pointed out.
Here in Australia, summer days can be...
bimr,
what other biocides can you suggest that are less corrosive than Sodium hypo? i really do not want to run a cooling tower with high corrosivity water that can later stuff up our turbine room heat exchangers.
thanks,
rmw and snorgy,
he turbine spec sheet says that the max inlet temperature in the generator and oil coolers are 25 Deg c . The leak off condenser can take a maximum of 27 deg C. So I guess, the condenser back pressure limit has been set up in such a way that it works fine as long as the inlet...
Mr BTU,
this HX was part of a mass & heat balance by an external company. they quoted 0.3 deg C approach. So I continud on that study but just changed the inlet conditions.
Snorgy,
Sorry for the typo..i meant cycles of concentration. :).
the cold water would be used for cooling our turbines and compressors. curently, they use untreated water at 15 degrees C.
Our mill uses a conservative wet bulb temp of 24 deg C for new cooling tower selections. this is for the...
