Abstract: What is disclosed is an improvement in a system for producing a vacuum in which both liquid and gas streams are involved. Specifically, in one aspect the improvement is in a vacuum system for extruding plastic pipe having conventional extrusion apparatus, vacuum tank, mold and vacuum and liquid pumps with a chilled water flow system, the improvement being characterized by an outer housing connected intermediate the effluent water conduit and the liquid pump with a vacuum port connected with a vacuum pump; and an internal sleeve interiorly of the outer housing defining an annular space about the sleeve and directing the combined stream directly into the entrance to the liquid pump so that by inertia the liquid is sucked into the liquid pump whereas the gas is diverted by the vacuum pump to maintain the pressure without flooding the vacuum pump.