Lovejoy / Sier-Bath Nyflex® and Mite®
    Lovejoy / Sier-Bath Nylon couplings are compact and require no lubrication. They operate over a wide temperature range at speeds up to 5,000 RPM and are effectively used in applications such as Motor/ Generator sets, pump sets, and many light to medium duty industrial coupling applications.

    No lubricants are ever required, eliminating the need for seals. The resilient nature of the nylon material makes the contact of the hubs and sleeves almost frictionless. Since no lubrication is used, the coupling can readily be adapted to many applications including vertical and blind installations where the slip-together components offer easy inspection and adjustment.
    Operationally, the coupling offers a minimum backlash solution that will operate in ambient temperature environments from -40° to 150° F. Nylon Sleeve couplings have precision molded sleeves and hubs with no bolts, pins, flanges, or protrusions to affect balance or safety. The nylon sleeve permits misalignment up to 5° for Dentex and Nyflex couplings and 3° for the Mite.
    When completely assembled, the Mite coupling weighs less than 1lb and the Nyflex only 3.50 lbs.
    The Nyflex and Mite coupling consists of two sintered iron flex hubs, one Nylon sleeve and two Spiirolox rings.
Unit of Measure




Hub Size



N/A Sleeves


N/A Nylon


N/A Sleeve


N/A 999999999


N/A 0.40 lb

Complete Coupling Weight

N/A 3.50 lb

Dimensional Data

Overall Length

N/A 1.880 in47.75 mm

Outside Diameter

N/A 3.75 in95.25 mm

Max. Bore (Dimensions ID1/ID2)

N/A 1.625 in41.28 mm

Length thru Bore

N/A 1.630 in41.40 mm

Distance between Shaft Ends (Dimension BSE)

N/A 0.13 in3.30 mm

Dimension HD

N/A 2.380 in60.45 mm

Dimension LS

N/A 1.880 in47.75 mm

Cubic inches

N/A 26.43750 in³

Performance Data

Max. Angular Misalignment

N/A 5.00 º



  • No lubrication required eliminating the need for seals
  • Sintered Iron hubs with crowned teeth to provider greater misalignment and gouging of nylon sleeve
  • Resilient, lightweight, abrasion and corrosion resistant nylon sleeve accurately molded to mesh with hubs eliminating friction and need of lubrication
  • Center groove in sleeves readily permits their use in vertical applications and for blind assembly
  • Securely held hubs and sleeves by spring-steel retaing rings yet capable of easy removal and still withstand a 5,000 lbs end thrust
  • Minimum backlash operating in an ambient temperature environment of -40 to 150° F