An Eccentric reducer, also called a Bell reducer, has two female (inside) threads of different sizes with centers so designed that when they are joined, the two pieces of pipe are not in line with each other, but they can be installed so as to provide optimum drainage of the line.

An eccentric pipe reducer fitting is designed with the smaller outlet off center to the larger end, allowing it to align with only one side of the inlet. The high quality reducer fittings are designed to be welded with ease and offer superior strength and leak resistance.

Eccentric pipe reducer must be installed with straight side up to prevent trapping air at the pump suction. They are designed to allows simple connection of different sized pipes. These can be used as pipe reducers flexible connectors and vibration eliminators.

Eccentric reducers eliminates noise and isolate vibration in the pipeline, reduces stress, eliminates electrolysis and protects against start-up surges.
They are fabricated using different materials like:

The advantage of an all-rubber reducer over a metal reducer is the flexibility and durability of the elastomer. Filled reducers are usually used on slurry and abrasive applications to prevent the collection of material, which can settle in the arches.