ACH 11.9 SN Reich OEM Drive Coupler Kit

The ACH 11.9 SN Reich OEM Drive Coupler Kit is a complete heavy-duty Arcusaflex flange coupling assembly used to connect a diesel engine flywheel to driven equipment such as a rotary screw compressor airend, hydraulic pump, generator, or marine gearbox. The Arcusaflex design absorbs torsional vibration from the engine firing pulses, dampens shock loads from the driven equipment, and accommodates angular and parallel misalignment between the engine and driven shafts.

This kit includes everything required to complete a full coupling replacement in one shipment:

The Reich Arcusaflex ACH 11.9 SN rubber disc element with vulcanized hub
The outer mounting flange that bolts the assembly to the driven equipment
16 socket head cap screws for the rubber element
Matching washer set for the screw assembly

The ACH series is the heavier-duty configuration of the Arcusaflex line, sized for higher torque applications than the standard AC and ACT series. The size 11.9 element handles substantial nominal torque loads with the SN element version – a balanced hardness rating that provides good torsional damping while maintaining high torque capacity.

The rubber disc element is the working component of the assembly. Cam gearing on the rubber element engages with the coupling flange to provide nearly backlash-free positive torque transmission while still allowing the disc to flex under torsional load. This combination of positive engagement plus elastomer flexibility is what makes the Arcusaflex design suitable for high-vibration internal combustion engine applications where rigid couplings would fail prematurely.

Common applications for the ACH 11.9 SN include large stationary rotary screw air compressors, diesel-driven gas compressors, large diesel generator sets, marine propulsion drivelines, and heavy industrial equipment with high-horsepower internal combustion drives. The axial plug-in design allows the coupling to be installed and removed without disturbing engine or driven equipment alignment – a major service advantage on large equipment where realignment is time-consuming.

During replacement, follow the Reich service documentation for the proper bolt torque specification on the 16 socket head cap screws. Inspect the existing rubber element for the failure mode (surface cracking, hardening, edge delamination, or set in compression) to identify whether duty cycle, operating temperature, or contamination is shortening service life. The complete kit approach restores the entire assembly to OEM spec rather than replacing only the failed component.

Stark Industrial Products carries Reich Arcusaflex OEM coupling components for industrial diesel engine and rotary screw compressor applications.