Spherical Clamp Up

[ttam]

I was researching different spherical clamp up strategies/configurations and stumbled across this old thread (thread31-443155). After reading through the thread and doing some additional searching, I came across this clamp up configuration (image below). I like it because the joint is constrained radially through both lugs (ignoring clamp up friction on flanged bushing) and is predominantly constrained axially through one of the lugs (ignoring the non-flanged bushing fit to the other lug). Limiting the axial retention to a single lug allows for the joint to avoid being over constrained and avoids introducing bending stress in the lugs during clamp up. Still need to consider eccentric loading in the lugs if the spherical isn't centered but the assembly could be shimmed.

 

[rb1957]

yes, the point of this complicated design is to avoid clamping across the lugs (across the tuning fork). The LH lug is unconstrained (along the axis of the fastener, the fastener is clamped onto the RH lug (between the shoulder bushing and the washer/nut.

another day in paradise, or is paradise one day closer ?

 

[WKTaylor]

I was confused by Your title and wording... the picture clarified immediately that You were discussing mounting of a Spherical BEARING.

I prefer using/specifying a shoulder bolt or an undersized common bolt with a high strength sleeve [shank-lengths equal]... + washer and nut.

I personally dislike lugs with in-line holes of different diameters and subsequently, different diameter shanks/flanges and grip lengths.

Regards, Wil Taylor
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[rb1957]

that is another simpler way ... have two sleeves around the bolt, extending beyond the outer faces of the lugs, so the bolt clamps up against the sleeves.

Very similar to as drawn ... why have the straight sleeve diameter > the shoulder sleeve diameter ?

another alternative is to have two should bushings, both on the same lug, one on the inner face, the other on the outer face; and a straight sleeve on the other lug as shown.

another day in paradise, or is paradise one day closer ?