Keys: It is virtually impossible to completely eliminate backlash between the key and the keyway, even after expensive and time-consuming machining and fitting. As a result, the continual impact between key and keyway leads to wallowing and pounding out. Further, keyed connections subjected to dynamic loads experience fretting corrosion at the shaft/bore interface. Adjusting the timing of matched components mounted with keys is difficult and time consuming. Finally, a keyway reduces the shaft cross section, effectively weakening the shaft.

Splines: Very expensive to manufacture, splines still do not eliminate the backlash problems cited above. Further, the notch factor for a spline is even greater than for a keyway, and timing adjustments are not an option.

QD or Taper Lock Bushings: The limited number of bolts in these devices generates a frictional torque capacity that is typically insufficient for most applications. Therefore, these connections still require a key, and all of the disadvantages cited above would apply. Furthermore, the axial movement between the inner and outer bushing during installation precludes defined axial positioning of the mounted component. In applications where this axial movement is restricted (e.g., in a roll or conveyor pulley), a substantial reduction of frictional torque capacity results as the second bushing acts to disconnect the first. Finally, difficult and expensive machining of tapered bores is frequently required.

Shrink or Press Fits: While these types of interference fits address some of the problems cited above, these approaches also present difficulties. Tedious calculations, extremely close tolerances, the need for heating and/or cooling apparatus or high-capacity presses or jigs, and cumbersome dismounting, especially in field installations, severely limit the overall effectiveness of these connections.

B-LOC is the solution!

• B-LOC Keyless Bushings provide a zero-backlash frictional connection that will never wear or pound out, and that transmits significant torque, thrust and/or bending loads.
• Our products mount and dismount easily with a clearance fit on both the shaft and drive element(s).
• Installation and removal is accomplished with readily available hand tools, typically an allen key and torque wrench.
• Component timing can be accomplished easily and repeatedly simply by loosening the screws to relax the locking device, adjusting the drive element, then re-tightening the screws.
• All of our devices have a straight OD, simplifying machining requirements for your part.
• All but one of our designs prevent axial movement of the drive element, meaning your part stays where you want it.