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
F16J9/06—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction using separate springs or elastic elements expanding the rings; Springs therefor ; Expansion by wedging
F16J9/061—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction using separate springs or elastic elements expanding the rings; Springs therefor ; Expansion by wedging using metallic coiled or blade springs
F16J9/063—Strip or wire along the entire circumference