PISTON RINGS

Piston rings are either one-piece or segmental and are made in a variety of materials, with PTFE the preferred choice for poorly lubricated applications. Piston rings must lie flat against the side of the groove to minimize the path for leakage. Metallic piston rings have a "free" diameter that is larger than the cylinder bore, causing the piston rings to maintain pressure against the cylinder wall to help seal at low pressure. Non-metallic rings depend almost entirely on gas pressure to effect a good seal.

101/101-X PISTON RINGS
The 101 piston ring is a multi-piece angular cut ring without an inner ring or expander. The 101-X piston ring is a 101 ring with an expander.

101-GD PISTON RINGS
The 101-GD piston ring has a grooved outside face with drilled holes in bore allowing high pressure gas into the outside groove. The GD feature is used to reduce pressure loading of the ring against the cylinder.

112/130 PISTON RINGS
The 112 piston ring is a multi-piece ring that features a step-cut outer ring and flat inner expander for applications where low leakage is desired. The 130 piston ring is similar to the 112 piston ring with a long flexible angle cut. The 130 is used for low temperature applications and where a stronger joint is desirable.

401-X PISTON RINGS
The 401-X piston ring has an expander contained by the ring to prevent groove side damage in the piston. The 401-X piston ring is used in low pressure applications.

204 PISTON RINGS
The 204 piston ring is a two segment ring used for compressor cylinders under 18" in diameter. With the segmented ring, the radial thickness can be heavier than normal without creating installation difficulties.