Timken Cone Bearings

Timken can tell you precisely, but I think you are correct. Tapered bearings should have line contact, not point contact, and if the bores are out of line, they will have a hard time establishing line contact. Ordinary machining errors of about .001" should be OK, but .010 - .020 seems too high to me. But call Timken, or visit their site.

Spherical bearings would handle that sort of misalignment easily, but they are costly.

IF The bearings are running "back-to-back", line-bored is the ONLYway to go.

If they're separated by a foot or more [or any distance] line-bored is still the BEST

way.

s.ricker

For any roller bearing the housing must be bored from the same single machine setup so that they are exactly in line. Anything else will yield poor bearing performance and life. Depending on what you are doing the housing mount must be square too. Dodge Special Duty bearings get around this with a special mount that allow the shaft to be concentric and perpendicular to the bearings.

Manufacturing engineer here. First, as a design engineer, you should state the requirements, not the process. It's up to the Manufacturing engineer to assure all the requirements of the drawing are met. State on the drawing the allowable miss-alignment, and leave it at that. (if you state the process and the process doesn't work, your on the hook. One designer called out the drill size, we used that drill but it didn't cut to the size he wanted.)

That said, I'm confused, you say you have a 3 in shaft and a 4.750 shaft? That's two shafts by my math, and that means you should be concerned with shaft miss-alignment not bearing housing, The shafts will ride in the center of the bearing housings, or did I miss something?

well first, there is no mech. engineer on this job. second there's kind of some drawings but we dont machine that shaft , so you have to read the numders and notations on the right side of the drawing. Oh did I mention the drawings prints are made from my drawings after the fact, some times WAY after the fact. now this sounds really crazy, but for the most part it works, well it has for @ 10 years, I work for a place that manufactures rock crushers MR. Lubyguy, I would really like to talk to you more on this, reason ....... they have never had anyone that thought of any of this things rdavis@caprock-spur.com thanks rdavis

I understand the shaft has different diameters. At bearing places the shaft dia is 3" and 4.75", right?