Companion FlangeWhat a Companion Flange Does
A companion flange, sometimes referred to as a hub, allows connection of a flange yoke to another type of connection, for proper torque transfer. The flange yoke is bolted with either through holes or threaded holes to the appropriate companion flange, which has some other form of connection, primarily bore and key or splined input shaft.

Why Machine Service, Inc can meet any Companion Flange requirement you have
At MSI we stock a complete line of standard size companion flanges with rough bore that we machine to fit your splined & keyed shafts. We have the capability to bore and key from DIN 58mm to 390mm, and from SAE 1310 to 1950 series, as well as spline bores and cross-serrate flange faces to fit your particular application. We also have machining capabilities that allow us to do special order jobs on material up to 750mm.

Companion Flanges for High Bearing Life Series

High Bearing Life


Bolt CircleBmm74.584101.5130155.5155.5196218245280310345385
Pilot HeightDmm2.
Hardware mmM8M8M10M12M14M16M16M18M20M22M22M24M27
# Bolts  46888108888101010

SLF Style (Standard Flange)

Max. Bore in1.5621.7502.1882.8753.5003.5004.5004.9375.5626.5006.2507.2509.125
Std. LengthEin2.002.002.503.
Hub Dia F in 2.417 2.562 3.250 4.312 5.187 5.125 6.687 7.437 8.406 9.687 10.88 12.09 13.47

SLF Style (Special Large Flange)

Max. Bore In1.7502.0002.7503.3754.1254.1255.2505.2506.5006.5008.2509.37510.50
Std LengthEin2.502.503.004.004.504.507.258.259.37510.2511.25As requiredAs required

SLF-OS Style (Special Large Oversized Flange)

Max. Bore In2.2502.6253.1253.9374.5004.5005.8756.5627.5008.2509.25010.2511.50
Std LengthEin2.502.503.004.004.504.507.258.259.37510.2511.25As requiredAs required
Through HoleHIn2.3752.3752.8753.7504.2504.2507.007.8759.0009.87510.75--

Companion Flanges for High Torque Series

High Torque Series


Bolt circleBmm196218245280310345385425492
Pilot HeightDmm4.556778101212
Hardware mmM16M18M20M22M22M24M27M30M30
# Bolts  888101010161616
Key WidthXmm3240404050708090100
Key DepthYmm912.5151516182022.522.5

SF Style (Standard Flange)

Max. Bore In4.4374.9375.5626.4377.2508.0008.9379.37511.500
Std LengthEin5.5006.0007.0008.0009.00010.00011.000As requiredAs required
Hub Dia.Fin6.6877.4378.3759.65610.84312.07813.45314.84417.484
Through HoleHIn4.635.0005.8756.8757.8758.7509.687--

SLF Style (Special Large Flange)

Max. Bore In5.8756.6257.5008.2509.12510.25011.37512.50014.250
Std LengthEin7.3758.0009.00010.00011.00012.00012.000As requiredAs required
Through HoleHIn6.5007.0007.8758.8759.87510.75010.688--