Bearing Selection
Bearing Selection
(OP)
Can any body provide the correct procedure for selecting Thrust Ball Bearing for Industrial Valve applications ? The information provided by Bearing Manufacturers does not cover this end use. The valve is only manually operated where the speed is low. If we select a bearing as recommended in manufacturers catalogs we end up with a big size bearing considering the life/speed etc. Is there any separate selection methodoly adopted by valve designers to make it economical ?





RE: Bearing Selection
Are you designing this valve? Valve bearings are typically sized by the valve manufacturer. Is this a glove valve, gate valve, etc. What are the seal requirements (pressures and fluid) along the valve shaft? The bearings also must be selected with consideration for lubricants and contaminants to or from the bearing to the fluid.
I found the following valve suppliers from a supplier of mine, Rust Instrumentation, West Jordan, Utah - Timken, Schrader-Bellows, Apollo, Asahi/America, Centerline, Flexible Valve, ITT Industries - Engineered Valves, Parker and Westlock. Maybe they can help.
RE: Bearing Selection
Yes. i am involved in the design of this valve. The subject equipment is a 8" Cl 600 globe valve. The calculated load ratings are higher than that of the bearing selected. i.e the bearing capacity is only 80% of the calculated rating.
Is it acceptable ? If not what is the correct industry practice ? It will be of immense help if some one can throw more light on this area/give a reference to where we can get this info. Sometimes, competitors/other manufacturers hesitate to provide such technical data. The bearings are totally isolated from the line pressure.
RE: Bearing Selection
RE: Bearing Selection
RE: Bearing Selection
We had a similar problem with tapered bearings. Are rates were very slow (0 to 2 degrees/sec). We were told that the static rating is for 0 RPM ONLY and that for spped between 0 and 5 RPM we were in no-man's land. For a 5 RPM rating they told us to multiply the 500 RPM rating by 4. They aslo stated that some of their customers use a factor of 6 because the load cases were infrequent and the movement did not occur under load. We had strict diameter constaints, so we ended with a larger bearing than needed anyway.
Bottom line is try to get good help from the bearing manufacturer.
RE: Bearing Selection
i have requested some of the bearing manufacturers. but haven't heard from them yet.