Oiling the engine's internal valves was done by adding oil to the steam supply, that could be done through a displacement lubricator.

Many domestic fire extinguishers use an internal valve identical to a Schrader valve, but with a lever on top to enable quick release of the pressurised content.

This is achieved by partial closing of an internal valve within the exhaust-the EXUP valve-at the point where the four primary pipes from the cylinders join.

The internal nasal valve comprises the area bounded by the upper lateral-cartilage, the septum, the nasal floor, and the anterior head of the inferior turbinate.

Eventually the internal valves wear out, but they are easy and cheap to replace.

With the gas flow directed by internal valves, the chambers alternately fill and expel gas, producing a near continuous flow through the meter.

The internal valve is usually only used as a safety precaution.

Video (5min 18sec), 28 Oct 2011: An internal valve prevents the K1 auto-disable syringe from being reused.

Reciprocating compressors operate efficiently in unloaded mode when flow to some of the cylinders is completely cut off by internal solenoid valves.

Tissue expanders have silicone outer shells and either an internal valve or external port to allow for saline fluid injections.