Lempor ejector

The Lempor ejector is a steam locomotive exhaust system developed by noted Argentine locomotive engineer Livio Dante Porta. The name is a combination of the names of Jean Lemaître and Porta.

In a steam locomotive, draft is produced in the firebox by exhausting the steam coming from the cylinders out of the chimney, or also by a blower. The Lempor ejector ejects differently from the conventional blastpipe; as one cylinder ejects it creates a vacuum in the other cylinder, thereby requiring less power to drive the piston.

The Lempor exhaust is claimed to deliver a 100% improvement in draughting capacity over traditional exhaust systems and a 40% increase in locomotive power.

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