Molded Rubber Expansion Joints
Spherical molded rubber expansion joints
are entirely different. There is no wire reinforcement in the body, and the pressure is
retained by the tire cord spanning across the body from anchors in each flange. They are
very similar to truck tires without the tread spherical expansion joints are built
straight. The curing process takes place in a steel mold clamped shut in a hydraulic
press. Heat is introduced from plates on either side of the mold rather than by steam. An
air bag is introduced in the center and pressurized to expand the body against the
contours of the steel mold where it is vulcanized.
We manufacture these expansion joints using Nylon. Polyester or DuPont Kevlar tire cord.
Our exclusive solid flange ring is clamped in place by the steel back up flanges. The
built in ring prevents the rubber from pulling out of the retention flange.
We manufacture this series in single and double spheres, as well as concentric reducers.
In the sizes up to 2" they are built with pipe unions.
Since these connectors are molded, there is a limitation on size, and face to face dimensions are fixed. The sealing principle is so effective,
however, that we have handbuilt this construction to very large diameters.
Molded expansion joints are kept in stock in Neoprene and EPDM.
They can be furnished in Nitrile, Hypalon® or other materials as well.