RRU Type - Drop-Out Style
    The RRU Type Uniflex coupling is designed for fast, easy installation and removal without disrupting the connected shafts. This is ideal when servicing impellers, bearings and seals. The design consists of two steel hubs fastened with cap screws to a Uniflex double flange coupling (UF Type). The RRU is easily disassembled by simply removing the cap screws and sliding out the UF center spring section.
    This design offers “quick disconnect” for drop out requirements. It can also accommodate a slightly larger shaft diameter than the standard U Type.
    Note: A complete RRU Type coupling is comprised of 2 hubs, 2 hardware kits, and a UF Type center drop out section.
Unit of Measure




Hub Style


Coupling Type

N/A Drop-Out


N/A Steel


N/A Gray/Metallic

Bore Type

N/A Rough Stock Bore


N/A 10.00 lb

Dimensional Data

Bore Size 

N/A 3/4 in


N/A RRU150

Set Screw Thread Size (Dimension T)

N/A No Setscrew

Keyway Size (W x D)

N/A No Keyway

Overall Length

N/A 7.660 in194.56 mm

Min. Bore (Dimensions ID1/ID2)

N/A 0.750 in19.05 mm

Max. Bore (Dimensions ID1/ID2)

N/A 2.125 in53.98 mm

Dimension BC

N/A 4.380 in111.25 mm

Dimension D

N/A 5.000 in127.00 mm

Flange Diameter (Dimension FD)

N/A 5.380 in136.65 mm

Dimension FL

N/A 0.620 in15.75 mm

Dimension FL1

N/A 0.500 in12.70 mm

Dimension HD

N/A 3.75 in95.25 mm

Dimension HL

N/A 2.120 in53.85 mm

Dimension S

N/A 3.440 in87.38 mm

Pin Location (Dimension SL)

N/A 0.820 in

Pin Size

N/A 3/8 in

Cubic inches

N/A 61.36213 in³

Performance Data

Max. Torque

N/A 1890.00 in·lb

Max. Speed

N/A 3000 rpm

Max. Recommended End Play

N/A 0.040 in1.02 mm

Max. Parallel Offset

N/A 0.041 in1.04 mm

Max. Angular Offset

N/A 3.00 º

Wind-Up Angle at Max. Torque

N/A 0.85 º

Rated HP at 100 rpm

N/A 3.02 hp

# of Set Screws Required per Hub

N/A 1

Normal Temperature Range

N/A -40 to 240 ºF

Max. Torque

N/A 213.5 N·m1890 in·lb

Coupling Design

Coupling Design

N/A Flexible Spring Type Coupling with Exclusive Triple Wound Spring Design
    The Uniflex Coupling is an all steel, single piece coupling that solves a variety of application concerns including: high misalignment, space limitations, high temperature, and exceptionally low backlash/windup. The unique flexing center of the Uniflex consists of three opposingly wound square wire springs for forward or reverse operation. Two steel hubs are then brazed to the steel spring pack to create a durable one-piece flexible coupling.



  • OAL Tolerance + .19 inch.
  • Total backlash is approximately 1/3 of windup at maximum torque – consult Lovejoy Engineering for more information.