POBCO-B Bearing Material

Why POBCO-B Wood Bearings Outperform the Competition

1. POBCO-B is a special close-grain dense hardwood that is fully impregnated (100%) with a combination of greases and waxes. The lubricant is solid at normal temperatures, flows when heated by friction, and retains lubricating properties indefinitely. Our Wood Bearings are 100% Dielectric, which prevents Static Electricity from developing.
   
   
2. POBCO-B bearings are machined cross grain. Due to the natural grain in wood, bearings can be manufactured in two different ways. Bearings manufactured with the bore of the bearing parallel with the grain are referred to as "Straight Grain" bearings. Bearings manufactured with the bore perpendicular to the grain are referred to as "Cross Grain" bearings.
   
   The tubular cells in wood are the pipelines that feed, meter and reabsorb lubricant. In straight grain bearings, these tubular cells terminate at the end faces of the bearing and do not lead to the interface between the bearing bore and the shaft.
   
   In Cross-Grain Bearings, tubular cells are exposed at the bearing interface, which allows for the lubricant to be fed directly to the journal surface where it is required. In rotating shaft, fixed bearing applications POBCO-B Cross-Grain Bearings allow for the porous grain openings to be 90 degrees from the direction of the applied load. This construction produces a low Coefficient of Friction (.09 ave.) and extended bearing life. (See Properties of POBCO Materials)
   
   
3. POBCO-B bearings are highly resistant to abrasion. This high resistance results from a combination of the relatively softer impregnated hardwood and the continuously self-generated lubricating film it provides. The lubricant in the bearing clearance area tends to repel foreign matter. Small particles reaching the bearing surface can become embedded in the bearing wall and are covered by the lubricant film. These excellent embed ability characteristics often prevent shaft-scouring. Hence, the life of the bearing and the attached equipment is extended.
   
   
4. Wood bearings that are machined in a straight grain manner and are not fully impregnated do not exhibit the outstanding characteristics noted above. Premature failure is a likely consequence of using a wood bearing manufactured in an inferior manner.