In four areas compression type couplings offer you benefits: torsional stiffness, safety, load capacity, and easy installation. At first, all elastomers especially synthetic rubber has higher load capacity in compression when compared to shear. Second, compared to shear types, compression types offer more torsional stiffness (less twist between hubs) with few versions closely approaching the very stiff characteristic of metallic couplings. Between the motor and driven machines, the backlash is minimized by this high torsional stiffness. For each incremental movement of the driving shaft, it offers the near-equal movement of the driven shaft which is among the important factors in certain conveyor and pump applications. Third, jaw couplings are fail-safe: even if the spider breaks the coupling can still operate. At a convenient time, the jaw coupling supplier can thus replace the spider, which in downtime can prevent critical systems. Only for this reason, in a well-designed and manufactured coupling, the jaws withstand several times the coupling’s torque rating.
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