Torque Limiter FMD 28


The FMD series from PT Tech is a multiple disc torque limiter that is friction-type that allows high energy, high horsepower and/or limited space applications. There are four sizes available in the FMD series which are designed to allow them to operate the drive system on the high speed side. Refer to the brochure or the chart below for the dimensional data. This FMD series of torque limiters can be produced to work with the Renold Hi-Tec PM Series Elastomeric Couplings or the American Vulkan Flexomax-GS Series Couplings. This all in one package allows the capabilities of misalignment and vibration damping capability in torque limiting. The quantity and strength of the spring-cups controls the torque setting of an FMD torque limiter. The characteristics of the operations are outlined in the Performance Data chart listed below. By adjusting the quantity and color of spring-cup assemblies, it allows the operator to verify the torque setting for any of the FMD torque limiters. Applications requiring special consideration is PT Tech’s business. For assistance, call our Engineering Department. All dimensions are subject to change without notice. Selection Procedure is STRICTLY intended as a general guideline. Consult us to finalize selection and for Reversing applications.

  • High Torque Capacity

  • High Energy Capacity

  • Consistent, Tamper-Resistent Torque Throughout Wearlife

  • Low Maintenance

  • Low Output Inertia

  • Designed to fit Renold Hi-Tec PM Couplings or American Vulkan Flexomax-GS Series Couplings, or Custom Designed for Your Coupling

Technical Specs

Max Torque 7,640 lb-ft 10,352 Nm
Max Speed 3,450 rpm
Outside Diameter 16.50 in 419.1 mm
Torque Limiter Length 6.67 in 169.4 mm
Outside Hub Length 5.65 in 143.5 mm
Max Bore 4.29 in 109.0 mm

Torque Settings

The FMD Series torque setting is preset at the factory. When the drive system torque exceeds the setting, the torque limiter will slip while continuing to transmit torque equal to the setting. This is possible because the static and dynamic coefficient of friction of the disc pack are almost identical due to proprietary design. 

The FMD series torque limiter is designed to operate at motor speed. In most drive systems the prime mover represents approximately 90-95% of the total inertia. The FMD series will generally provide excellent inertial shockload protection when located at the prime mover.