The patented Deltaflex series of couplings offer maximum misalignment capabilities with negligible reactionary load, for longer equipment life. This all-metal flex-link coupling requires no lubrication or other maintenance.

Standard (Type 1, 2, or 2A) Deltaflex coupling are comprised of two hubs, an inner flange (with hardware), and an outer flange. Spacer (Type 3 & 4) Deltaflex coupling are comprised of two hubs, two spacer flanges (with hardware), and a drop out spacer.

Unlike Delta hubs, Round hubs are available in stainless steel (SS). Round hubs can also accommodate a larger max bore, but must always be mounted externally (no internal Type 1 mounting). Standard Round hubs come with two set screws at 120º.

Unit of Measure



N/A 50 HUB RND SS 1-1/8 1/4X1/8KW

Hub Style

N/A Round

Coupling Type

N/A Flex-Link


N/A Stainless Steel


N/A Metallic

Bore Type

N/A Finished Bore


N/A 2.26 lb

Dimensional Data

Bore Size 

N/A 1 1/8 in


N/A 050

Set Screw Thread Size (Dimension T)

N/A 1/4-20

Keyway Size (W x D)

N/A 1/4 x 1/8 in

Length thru Bore

N/A 1.68 in

Min. Bore (Dimension ID)

N/A 0.440 in

Max. Bore (Dimension ID)

N/A 2.250 in57.00 mm

Dimension BC

N/A 3.080 in78.23 mm

Dimension HD

N/A 3.560 in

Dimension P

N/A 1.998 to 2.000 in50.749 to 50.800 mm

Dimension Q

N/A 0.090 in2.29 mm

Dimension TH (Axial Cap / Screw Tap)

N/A 5/16-18 x 0.75

Cubic inches

N/A 19.89755 in³

Performance Data

Max. Continuous Torque

N/A 1900.00 in·lb

Peak Overload Torque

N/A 2850.00 in·lb

Rated HP at 100 rpm

N/A 3.00 hp

Rated HP at 875 rpm (Standard Motor)

N/A 26.20 hp

Rated HP at 1,150 rpm (Standard Motor)

N/A 34.00 hp

Rated HP at 1,750 rpm (Standard Motor)

N/A 52.40 hp

Rated HP at 3,500 rpm (Standard Motor)

N/A 105.00 hp

Coupling Design

Coupling Design

    The Deltaflex coupling is the real solution to installation, misalignment, and performance problems. Conventional couplings – even when carefully aligned to the manufacturer’s specifications – cannot match the low level of vibration, moment of inertia, and additional cushion for future misalignment of a visually aligned Deltaflex coupling.
    In addition, the Deltaflex coupling gives longer life to equipment shaft bearings. That means longer operating time and reduced maintenance cost. The Deltaflex can handle greater shaft misalignment without generating heavy reaction loads on the equipment shaft bearings.
    A properly applied and installed Deltaflex coupling offers more equipment protection compared to conventional couplings.



  • Maximum misalignment capabilities, with negligible reactionary load, for longer equipment bearing life
  • Operates as smoothly when misaligned as when perfectly aligned
  • No lubrication and no maintenance required
  • Equipment can be visually aligned. No special tools are required, which saves on installation time and cost
  • Eliminates premature equipment bearing and seal failure resulting from misalignment forces. This means greater equipment productivity
  • Torsionally stiff coupling with no backlash means it is capable of high speed applications, within catalog ratings
  • Provides long-term performance and economy
  • Available in 5 basic sizes, from 10HP to 900HP
  • Standard all-metal and stainless steel versions are both available from stock
  • Many configurations are available, including shaft-to-shaft, spacer, floating shaft, and special assemblies



  • Size 50: In some bore sizes the tap is 5/8-18.
  • Maximum bores are provided with standard keyway.
  • RSB hubs do not have a keyway.
  • Both Delta hubs and Round hubs are provided with two set screws at 120°.