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Reliability Warriors. Downtime Destroyers.

High Performance Gear Couplings

High Performance images
  • Dynamically balanced
  • Fasteners are weigh balanced
  • Body fitted bolts in reamed holes
  • Precision manufactured close tolerances
  • Custom design assistance
  • Available in sizes from 1 through 30 depending on model

Lovejoy High Speed and Engineered Special Gear Couplings satisfy a specific engineering need for custom coupling designs that require additional engineering. While standard components do exist, the unique requirements of individual applications will customize a coupling design. (For stock gear couplings, please see our Gear Couplings product page.)

High Speed - The Lovejoy / Sier-Bath F Series High Speed gear couplings are designed for exacting high speed, high efficiency performance beyond the ranges and limits of standard coupling specifications. Typical applications include high speed centrifugal and axial flow compressors, gas turbines, steam turbines, test stands, etc. High speed couplings are dynamically balanced as assemblies and match marked. Fasteners are weigh balanced in sets. Major diameter fit gear teeth, precision machined tolerances, and high quality components help to reduce the potential unbalance in the coupling assembly.
Engineered - Many of the components are standardized, but the special requirements of certain applications will customize each design. These couplings require specific customer input to properly design the coupling to suit the application.

FHS High Speed Close Coupled
  • Similar to standard F Type gear coupling; much tighter tolerances
  • Maximum speed is for assembly balanced couplings
  • Component balancing available; may result in lower max speed
  • Material: AISI 1045 steel

FHSA High Speed Standard
  • Alloy Steel (core hardness of RC30-35); magnetic particle inspected
  • Precision manufactured w/ ground bores & concentricity for dynamic stability
  • Dynamically balanced, piloted gear fit, body-fitted bolts in reamed holes
  • For nitrided teeth - specify Class AN & 85.5 min surface hardness on Rockwell 15N scale

FHSAA High Speed Precision
  • Alloy Steel (core hardness of RC30-35); magnetic particle inspected
  • Precision manufactured, dynamically balanced, piloted gear fit, body-fitted bolts in reamed holes.
  • Low overhung moment, low moment of inertia, and extremely light weight. Balancing bands will be included, if required. 
  • For nitride gear teeth - specify Class AAN & 85.5 min surface hardness on Rockwell 15N scale.

FHSPAA High Speed Ultra Precision
  • Nitralloy 135 modified (core hardness of RC 32-36); magnetic particle inspected. 
  • Precision manufactured, dynamically balanced, piloted gear fit, body-fitted bolts in reamed holes.
  • Low overhung moment, low moment of inertia, and extremely light weight. Balancing bands will be included, if required. 
  • For nitrided gear teeth - specify Class PAAN & 90 min surface hardness on Rockwell 15N scale.

FHSMA High Speed Marine
  • Core hardness of RC 30-35; magnetic particle inspected
  • Precision manufactured w/ ground bores & concentricity for dynamic stability
  • Dynamically balanced, piloted gear fit, body-fitted bolts in reamed holes, & larger shaft capability
  • For nitrided teeth - specify Class MAN & 85.5 min surface hardness on Rockwell 15N scale

For performance data: please download catalog or contact Lovejoy Engineering.