Eccentric Reducers

Eccentric reducers have a changing centreline for the bore, with one side remaining parallel. Eccentric reducers are used at the suction side of pumps to ensure air does not accumulate in the pipe. The gradual accumulation of air in a concentric reducer could result in a large bubble forming that could eventually cause the pump to stall or cause cavitation when

drawn into the pump, with the flat side in the upper position this is avoided. Also eccentric reducers can be useful with the flat side down to allow for the complete draining of pipelines and preventing the pooling of liquid which can happen with concentric reducers in horizontal piping.

The dimensions below are to suit ASME 150 flanges.

To Suit Pipework NB Face – Face A Offset B
Large Bore Small Bore
Inches mm Inches mm mm mm
3/4″ 20 1/2″ 15 114 3
1″ 25 1/2″ 15 114 6
1″ 25 3/4″ 20 114 3
1.1/2″ 40 1″ 25 114 7
2″ 50 1″ 25 127 13
2″ 50 1.1/2″ 40 127 6
3″ 80 1″ 25 152 28
3″ 80 1.1/2 40 152 20
3″ 80 2″ 50 152 14
4″ 100 1.1/2 40 178 33
4″ 100 2″ 50 178 21
4″ 100 3″ 80 178 13
6″ 150 3″ 80 229 40
6″ 150 4″ 100 229 27
8″ 200 4″ 100 279 52
8″ 200 6″ 150 279 25
10″ 250 6″ 150 305 52
10″ 250 8″ 200 305 27
12″ 300 8″ 200 356 52
12″ 300 10″ 250 356 25
14″ 350 8″ 200 406 68
14″ 350 10″ 250 406 41
14″ 350 12″ 300 406 16

Typically supplied as a transfer moulded PFA lined investment cast steel construction, we use fabrications and PTFE liners for reducers  fitted with rotating flanges etc.