Elastomers in shear are generally used in mounting and suspension applications. Urethane elastomers deflect more easily in shear than in compression. Deflection of a urethane system in shear is a function of three things: the shear stress, the shear modulus – G – of the urethane compound, and the thickness of the urethane.

For bonded urethane applications used in shear, it’s pivotal that certain design guidelines are followed. When under shear loading, the bond line is in tension. By utilizing generous fillets, stress risers are eliminated or greatly reduced at the bonded interface.

In every application that would use the high shear strength of urethanes, the weakness is the dependence on a good bond between the urethane and metal. There are specific ways Gallagher has successfully overcome this weakness. Contact us to learn more.

Shear Strain

deflection-thickness

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Deflection

Polyurethane deflection