Corrosion on crevice of bearing

Desdemonaaa

Filing Flight Plan
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Desdemonaaa
Hello, was looking for info on corrosion found on a bearing. Is there a high chance of corrosion inside the crevice? And would it effect the parts ability to not fail or cause the bearing to pop out? The bearings are pressed in and are a flight critical parts. Thanks for any help on the topic20190923_140344.jpg 20191009_164739.jpg
 
Looks to be surface rust on the outside of a spherical bearing receiving hole. Can you see play in the bearing?
 
was looking for info on corrosion found on a bearing. Is there a high chance of corrosion inside the crevice?
What area are you calling "corrosion" and the "crevice?" The gray/silver ball area is a coated area usually teflon or something similar and the brown/reddish ragged line next to the ball area appears to be the edge of the phenolic material or something similar that the coated ball area rides against within the link housing. But I really don't see any corrosion from these pics???
The bearings are pressed in and are a flight critical parts.
Helicopter? What model?
 
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It would really help to know what that bearing is on. But that looks like surface corrosion, I would watch it, but not be too concerned about it, depending on what it does.
 
Looks fine to me. The brown stuff against the ball is likely the sintered bronze bearing itself, and the brown streak outside the bearing shell is too bright to be rust. Might be the adhesive that holds the bearing in the rod end.
 
Looks more like dried out lube. Needs to be disassembled and the spherical ball cleaned and then felt by hand for wear and roughness. Any movement of the ball axially or radially is typically cause for replacement, but depends on the system and manual specifics.

High cycle rodends and bearings will leave a tell tale black streak, which the pics above don't show. The bearings in the aft elevator bell crank on Navajos and Chieftans are like that. If you see black, time to replace.
 
Looks more like dried out lube.
FYI: if that bearing is what I think it is, they are actually self-lubricating type bearings. No disassembly or lubrication possible. Actually if any lube is applied it reduces the life of the bearing. The "dried lube" you mention is more edge of the PTFE/phelolic material bonded to the interior of the link housing. The rod-ends you mention could be disassembled via the retaining rings and the actual ball-bearings relubed with grease. The ones pictured above have no ball-bearings, only a internally bonded bearing fabric on which the the coated ball rides on. Short of the bearing fabric migrating out of the link housing the only indicator to replace them is via axial/radial play. We'll see if the OP will respond with more info.
 
FYI: if that bearing is what I think it is, they are actually self-lubricating type bearings. No disassembly or lubrication possible. Actually if any lube is applied it reduces the life of the bearing. The "dried lube" you mention is more edge of the PTFE/phelolic material bonded to the interior of the link housing. The rod-ends you mention could be disassembled via the retaining rings and the actual ball-bearings relubed with grease. The ones pictured above have no ball-bearings, only a internally bonded bearing fabric on which the the coated ball rides on. Short of the bearing fabric migrating out of the link housing the only indicator to replace them is via axial/radial play. We'll see if the OP will respond with more info.

Depends on the part number. P&WC has lubing procedures for their rod ends. Beech engine control rod ends are teflon and are supposed to see no lube. The teflon ones are identified with a white seal around the bearing. But there are so many variations and types.

As stated, more info is needed to give a decent internet guess.
 
It does look like a self-lubricating PTFE liner. Note that they can have some play and still be perfectly acceptable. Some are even designed with clearance when new to minimize the initial breakaway torque.


What’s the part number, manufacturer, and/or cage code listed on the OD?
 
P&WC has lubing procedures for their rod ends. Beech engine control rod ends are teflon and are supposed to see no lube.
Agree. But my guess the OPs pics are of helicopter flight control link bearings at the swashplate and not an engine control linkage. And considering they have data tags on them probably are tracked components.
 
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