Customized Laminated GPZ Pot type bridge rubber bearings

Pot Bearing consists of a steel pot, filled with an elastomeric disc and a piston plate (lid). The elastomeric disc is used to support an almost limitless vertical load. The elastomeric disc is made of rubber and behaves similarly to a liquid while its volume simply does not change during compression. It has a Poisson's ratio of 0.5. The load is also able be uniformly distributed to the pot and rotations can occur, due to the feature of liquidity and flexibility.

The disc is sealed by typically brass rings, which are important element to confine the disc in the pot so it does not escape. Horizontal forces are transmitted from the piston to the pot. To release one sliding direction, an additional element, acting as a guide bar, becomes necessary for these guided-sliding bearings. A sliding material (usually PTFE or UHMWPE) is recessed on the top of the piston plate and slide against the stainless steel plate connected to the bottom surface of the top steel plate.
PTFE is a plastic with high mechanical and chemical resistance, great roughness and low friction when combined with polished stainless steel.
Particular bearings can also be designed using this principle to cater for other combinations of loads such as lifting force or extra high horizontal force.
Design rotation for common pot bearing shall exceed ±0.02 rad. Coefficient of friction of sliding parts shall be designed no more than 0.03.