Sequence of press fits
Sequence of press fits
(OP)
In this example, there are a couple of ways of completing the task of replacing the bearing in the field. The factory does not recommend the field operation, they recommend removing the control arm and use a press (major job and super time consuming). The question is which field method would be the best. The press fit between the bearing and spindle and bearing and hub is .001+
1. Freeze spindle (in refrigferator 0-10F) - heat bearing at 200F in oven - slide bearing onto spijndle. Since these parts are small and removable a press could be used. Question would heat be bad for the bearing. Then as an assembly, freeze spindle and bearing - heat control arm housing and drive spindle/bearing into housing. - Question would the driving force from a hammer damage the bearing.
(note:spindle is not long enough to to pulled thru via threads and a nut.
2. Freeze bearing (I have noticed moisture inside bearings when doing this even is bearing is in a sealed bag. could this moisture cause failure down the road) - heat housing and install bearing.
Here is the problem with this method - Freeze the spindle but what do you do with the bearing? cant really heat it.
Good thing about this method is the bearing can be pressed in using a ball joint. Spindle is too large for a too like that.
[URL=http://s1052.photobucket.com/user/johnfin1/media/b...]
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1. Freeze spindle (in refrigferator 0-10F) - heat bearing at 200F in oven - slide bearing onto spijndle. Since these parts are small and removable a press could be used. Question would heat be bad for the bearing. Then as an assembly, freeze spindle and bearing - heat control arm housing and drive spindle/bearing into housing. - Question would the driving force from a hammer damage the bearing.
(note:spindle is not long enough to to pulled thru via threads and a nut.
2. Freeze bearing (I have noticed moisture inside bearings when doing this even is bearing is in a sealed bag. could this moisture cause failure down the road) - heat housing and install bearing.
Here is the problem with this method - Freeze the spindle but what do you do with the bearing? cant really heat it.
Good thing about this method is the bearing can be pressed in using a ball joint. Spindle is too large for a too like that.
[URL=http://s1052.photobucket.com/user/johnfin1/media/b...]
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RE: Sequence of press fits
Do you accept responsibility for using a different procedure?
... When it goes sideways?
Is this part of an airplane?
Mike Halloran
Pembroke Pines, FL, USA
RE: Sequence of press fits
RE: Sequence of press fits
With example shown, there is a retaining ring that holds the outer bearing race in place in the suspension arm, and the retaining ring likely cannot be installed with the hub fitted inside the inner bearing race. So it seems likely the bearing needs to first be installed in the suspension arm.
RE: Sequence of press fits
RE: Sequence of press fits
"(The snap ring) goes on the hub first either when the bearing installed on the hub or when the hub in pressed into the bearing inside the control arm."
Have you taken this apart yet?
It looks to me like the snap ring fits in a groove in the Control Arm, not on the hub.
Functionally that is where it is needed, as a failsafe for the bearing sliding axially in the CA..
The bearing inner race is captured axially when nut 9 clamps drive flange 10 against unmarked hub.
Like Tbuelna said, the snap ring would likely have to be installed after the bearing is in the control arm, and before the hub ( item number cut off in picture ) and is installed.
The few-to-several 1000 lb forces needed to Install the bearing in the CA and to pull the hub into the bearing likely could be provided with a large threaded rod. Fixtures/adapters might be made from bits from Loew's plumbing department. Also as Tbuelna said, the force must be applied to the race being installed. Doing that while Removing the bearing from the CA may prove difficult, as the inner race may be all that is exposed, but I guess you will replacing it anyhow.
RE: Sequence of press fits
RE: Sequence of press fits
RE: Sequence of press fits
RE: Sequence of press fits
RE: Sequence of press fits
A piece of pipe with ID .01" larger than the bearing ID, and nut number 9 would pull the spindle into the bearing (already installed in the hub). It might take a few pieces of pipe of various lengths.
An alternative is welding some all-thread to an old #9 nut with an intermediate transition. This would permit pulling the spindle into the bearing in one continuous pull, applying force only to the bearing inner race.
A little like this -
http://tech.corvettecentral.com/wp-content/uploads...
When assembling shrink fits I want to have Plan B all set to go to mechanically seat the parts if the pieces stick half way home.
RE: Sequence of press fits
The combined radial, axial and moment forces applied to that duplex angular contact ball bearing during operation have been carefully analyzed. On the other hand, you have no way of knowing what forces will be applied to the bearing using your installation approach. It would not take much excessive axial force applied to the bearing balls to cause brinelling damage to the race surfaces. When that happens, the bearing will quickly suffer spalling failure.
You should first thermal fit or press fit the new bearing into the control arm by applying force only to the outer bearing race. Install the retaining ring. Then you can thermal fit or press fit the hub into the inner bearing races by applying force between the threaded end of the hub and the inner bearing race end face. This way no axial force is applied to the bearing balls. Like Tmoose says, make a long outer sleeve that has the same diameter as the inner race and an internal thread at the other end. Then make a jackscrew that connects to the hub flange thread at one end and mates to the internal thread in the sleeve. This device will pull the hub shaft into the bearing inner race without placing any load on the bearing balls or outer race.
RE: Sequence of press fits
Similar to this very successful in-situ ball joint installer.
http://www.sptool.com/images/stories/68600%20combo...