The ACT4ST Reich Arcusaflex Drive Coupler is an OEM coupling from the Reich ACT series, size class 4 with taper-lock hubs. The taper-lock configuration provides higher clamping force and better concentricity than standard keyway bores, making it the preferred choice in applications with elevated torque demands or frequent start-stop cycling.
ACT4 taper-lock couplers are specified in mid-range portable compressors and industrial equipment where the shaft connection must handle sustained high loads without loosening. The taper-lock interface eliminates keyway stress concentration, which extends shaft life in high-cycle applications.
When replacing, follow the manufacturer’s specific procedure for taper-lock hub removal and installation. These require a defined torque sequence on the locking screws to achieve proper clamping force. Do not reuse worn taper-lock hardware. Verify alignment after installation.
Stark Industrial Products stocks taper-lock Arcusaflex couplers for compressor and industrial applications.



















