In a steam locomotive, draft is produced in the firebox by exhausting the steam coming from the cylinders into the Chimney via a nozzle or 'blast pipe' this creates a vacuum in the Smokebox. The Lempor ejector is a development of similar multiple orifice/nozzle ejectors which create either a stronger vacuum or the same vacuum more efficiently by presenting less 'back pressure' or resistance to the exhausting cylinder.
Results
The Lempor exhaust is claimed to deliver a 100% improvement in draughting capacity over traditional exhaust systems and a 40% increase in ejector performance.[2][citation needed]