F
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16
ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
F16J
PISTONS; CYLINDERS; SEALINGS
F16J9/00
Piston-rings; , e.g. non-metallic piston-rings; , seats therefor; Ring sealings of similar construction
F16J9/08
with expansion obtained by pressure of the medium