Compression Hubs and Bushings

XT, QD and Taper Lock Series

The XT series hub is the industry preferred offering for conveyor pulley applications. It was designed specifically for rigid end disc drum and wing pulleys to reduce the occurrence of end disc failure as a result of shaft bending moments being transmitted to the hub and end disc.

XT Series Features

• XT hubs are extra wide where the pulley load is carried, providing a more stable base of support. This prevents fretting movement and limits hub rocking and subsequent bolt fatigue. The wider hub is also less susceptible to weld distortion.
• The XT bushing is thicker through the barrel under the hub. This makes it more capable of supporting the constant rocking pressure of the hub, and also allows deeper keyseats.
• The XT series has a 2” taper per foot which is steeper than the 3/4 ” taper per foot on QD, and a greater number of bolts than the QD series. The steeper taper requires less axial movement in order to compensate for hub expansion as the bolts are tensioned. This results in less end disc pre-stress as compared to QD series. The steeper taper also makes the XT an excellent alternative to the Dodge HE series.
• Lynx Products hubs and bushings are manufactured from 1045 steel which results in less keyway deformation under torsional stress and provides stronger threads.
• Bushings are standard with black oxide coating for corrosion resistance.
• Tight tolerances on the radial relationship between the bushing keyway and mounting holes ensure consistent mounting for replacement parts, and are interchangeable with other manufacturers.

XT Installation Instructions PDF 128KB

QD series hubs and bushings are also available from Lynx Products. Originally designed for sprocket and sheave applications, the QD series has also been used for conveyor pulley applications. The 3/4 ” taper per foot on the QD offers a higher mechanical advantage over steeper tapers, but also results in higher pre-stress to the end discs which can lead to premature end disc failure. The XT series’ steeper taper and greater number of bolts produce comparable clamping force to the QD, but with reduced end disc stress. Lynx Products’ QD series hubs and bushings are also manufactured from 1045 steel, and incorporate the same tightly controlled radial tolerances between keyways and mounting holes as the XT series.

QD Installation Instructions PDF 90.1KB

Taper Lock hubs and bushings are also available from Lynx Products. They are typically used in lighter duty unit handling conveyor applications where space constraints between the end of pulley and the frame prohibit use of XT or QD series. The Taper Lock bushings half thread configuration can often result in uneven tightening of the bolts which can contribute to run out of the pulley and loosening of the bushing during operation. For these reasons Lynx Products discourages the use of the Taper Lock series in conveyor applications except in cases where other options are not practical.

Taper Lock Installation Instructions PDF 148KB