Molded diaphragms are composed on tough, flexible, carefully engineered laminates. In general, the laminates have two basic elements:

Elastomer: One or two pressure-tight layers of tough elastomeric (synthetic rubber) material selected (or specially compounded) for long life under a specific set of operating conditions (fluid type, temperatures, etc.). Depending on the application, the elastomer is bonded to one or both sides of a fabric base.

Fabric: A high tensile strength base layer of specially woven fabric, designed to withstand the stresses induced by high pressures. Medium tensile strength base fabrics are also available that have been specially knit for ultimate sensitivity and low hysteresis.

Other Materials: Depending on the application, diaphragm construction may also use an aluminum or plastic insert to serve as a piston or rigid backing for a valve seat. In some cases, a PTFE layer may also be added to improve resistance to harsh chemical and abrasion.

The Elastomer	The Fabric	The Laminate