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Elastomers
Lovejoy offers four types of elastomer designs to allow for additional flexibility in addressing specific application requirements. One piece designs are used in the "L" and "AL" models (referred to as spiders) and multiple part "load cushions" are used in the "C" and "H" model couplings. The load cushions are in sets of 6 to 14 pieces depending on coupling size. Solid Center Spider - The solid center design is the most commonly used in general power transmission applications when the shafts of the driver and driven can be kept separate by a standard gap. Open Center Spider - The open center spider design allows the shafts of the driver and driven to be positioned within a short distance. Open center spiders offer shaft positioning flexibility but have a lower maximum RPM capability. (1750 RPM max. for NBR, 3600 RPM max. for Urethane / Hytrel.) Cushions - The cushion design is available exclusively for the Lovejoy Types C and H jaw couplings. The load cushions are held in place radially by a steel collar which is attached to one of the hubs. This design allows for easy installation and removal of the load cushions. The cushion design has the same engineering purpose as the spider designs but is more effective in the heavy duty applications that Types C and H couplings address. Snap Wrap Flexible Spider - The snap wrap flexible spider design allows the spider section of the coupling to be easily installed or removed without disturbing the coupling hubs. This design also allows for close shaft separations all the way up to the hubs maximum bore, which is not possible with open center spiders. Maximum RPM is 1750 with retaining ring, but if used in LC Type (with collar). Spider Materials SOX (NBR) Rubber - Nitrile Butadiene (Buna N) Rubber, a highly flexible insert material that is oil resistant, is our standard elastomer. It resembles natural rubber in resilience and elasticity, and operates effectively in temperature ranges of -40º to + 212º F (-40º to +100ºC). (Also applies to SXB Cushions.)
__________________________________________________________________ Urethane - Urethane has 1.5 times greater torque capability than NBR and offers good resistance to oil and chemicals. However, this material provides less dampening effect and operates at a temperature range of -30º to +160º F (-34º to +71ºC).
__________________________________________________________________ Hytrel - Hytrel is a flexible elastomer designed for high torque and high temperature operations. Hytrel can operate in temperatures of -60º to +250º F (-51º to +121ºC) and has an excellent resistance to oil and chemicals. It is best used in continuous load applications rather than cyclic or on / off service.
_____________________________________________________________________ Bronze - Bronze is a rigid, porous, oil-impregnated metal insert exclusively for low speed (max. 250 RPM) applications requiring high torque capabilities. Bronze performance is not affected by water, oil, dirt, or extreme temperatures — operates in temperatures of -40º to +450º F (-40º to +232º C). |
