Nitrile
General-purpose oil and fuel resistance for moderate-duty sealing applications.
S-Seal
Moss Seal supplies S-seals for demanding high-pressure applications where multi-piece seal stacks are difficult to install or prone to assembly error. Each S-seal combines a precision-molded elastomer sealing element with metal springs bonded into the heels during molding. The result is a single component that seals, resists extrusion, and installs in one step. We match elastomer compound, spring alloy, and cross-section to your pressure, temperature, and fluid, from casing and tubing hangers to valve stems, packers, and other static or slow-moving oilfield equipment.
ENGINEERING
Cross-section design & operation
Open-coil springs are molded into the low-pressure corners of an elastomer body, so the seal carries its own extrusion protection and needs no separate back-up rings.
Ring styles
The elastomer body is shaped as an ID or OD sealing element with a spring seated in each heel. The springs are wound with no initial tension so rubber flows between the coils during molding, locking spring and elastomer together as one part.
How it works
On installation, the elastomer is compressed to create the initial seal. As pressure rises, it loads the elastomer against the mating surface and toward the clearance gap, where the molded-in spring bridges the gap and stops extrusion.
Pressure response
The springs flex with pressure fluctuations, opening and closing to follow small movements in the hardware while keeping the extrusion gap blocked. This keeps the seal effective through pressure cycling and thermal growth without nibbling or blow-out.
SELECTION
Materials & advantages
Performance advantages
One-piece installation · Molded-in extrusion protection · No loose back-up rings · Handles pressure cycling · Resists nibbling and blow-out · Fewer assembly errors
