Power Transmission Engineering Magazine
www.powertransmission.com/articles/8121

Zero-Max Posi-Lok Keyless Shaft Bushings Provide Secure Shaft-Hub Connection

May 27, 2021
Zero-Max offers a variety of options within the Posi-Lok keyless shaft bushings (PSL) product line. Options include material choices, plating, and different mounting methods. These options give system designers the ability to select the best shaft locking device for their system. The PSL series allows the user to rigidly and reliably secure shaft mounted components into position for optimal operating results in their machine. 

Posi-Loks are a superior shaft-hub locking solution, eliminating the need for keyways which can weaken or cause excess wear to shaft components. All Posi-Lok models easily slide onto a shaft for mounting and provide reliable, zero-backlash performance. They provide excellent concentricity with minimal radial and axial runout. Since the Posi-Lok’s field-proven mechanical design does not require a keyway, it reduces machining costs and simplifies installation. The Posi-Lok choices are as follows:

Posi-Lok-K Series is a single taper, flanged design, and is available in 4 different models.  
The PSL-K model offers an unplated alloy steel construction with black oxided socket head cap screws for mounting.

The PSL-K-B has the same construction as the PSL-K, but includes black oxided hex head screws to allow radial access for mounting the bushing in applications with limited axial space.

The PSL-K-C has a nickel plated steel construction, and uses plated, socket head cap screws for mounting in applications that require corrosion resistance.

The PSL-K-F is a stainless steel version of the PSL-K series, with specially coated stainless steel socket head cap screws for mounting in applications requiring a stainless steel material.

With all the versions of the PSL-K series having the same mounting dimensions (shaft diameter, hub bore, and length), there is a variety to choose from to get the ideal arrangement for your machine. The PSL-K series can be interchangeable between the various styles in many applications. The PSL-K series supports Metric and English shaft sizes, and are available for use with shaft sizes from 6 mm to 42 mm and ¼ inch to 1 inch.

Posi-Lok-G Series is an economical, dual taper design, offering the highest torque capacity in the Posi-Lok family.  It is directly interchangeable with a handful of other brand bushings. It has a flangeless design, so it can be recessed in the bore of the mounted component for space saving. It is also available in the PSL-G-C series, which is a nickel plated version having the same dimensions as the PSL-G, adding a corrosion-protected option to the line-up. The PSL-G series supports shaft sizes from 19 mm to 120 mm.

Posi-Lok D Series is a single taper flangless design, allowing for a smaller OD and size for the connected component. It is also available in a PSL-D-C model with nickel plating for corrosion protection. The PSL-D series are available for shaft sizes from 6 mm to 50 mm. 

Posi-Lok M Series is a single taper design with a stepped flange that provides a self-centering feature and increased concentricity in an alloy steel construction. It is available for shaft sizes from 20 mm to 50 mm.