What Is The SPNS Step Seal?-jst-seals.com

What is the SPNS Step Seal?

April 14. 2025

The SPNS (Step Seal with PTFE and O-Ring Energizer) is a static hydraulic rod seal installed in gland housings to prevent fluid leakage during rod reciprocation. Its design includes:

PTFE Slip Ring: Provides ultra-low friction, chemical resistance, and thermal stability.

Elastomeric Expansion Ring (O-Ring): Compensates for PTFE’s rigidity by supplying elasticity and initial sealing force.

Bronze-Filled PTFE: Enhances wear resistance and reduces extrusion risk under high pressure.

This two-component system ensures reliable sealing in applications where traditional polyurethane seals fail.

SPNS seals excel in environments where low friction, corrosion resistance, and media compatibility are critical:

Hydraulic Cylinders in marine or offshore equipment (exposed to saltwater/oil emulsions).

Industrial Machinery handling water-glycol or fire-resistant hydraulic fluids.

Mining Equipment operating in abrasive, high-pressure conditions.

Chemical Processing Systems requiring resistance to aggressive media.

Advantages:

1.Chemical resistance

2. Heat resistance

3. Low friction

4. Has good oil return property

5. Easy installation

6. Longevity

7. High-pressure resistance

The PTFE SPNS Step Seal is a game-changer for hydraulic systems demanding low friction, chemical resistance, and reliability in extreme conditions. By pairing PTFE’s unmatched material properties with a precision-engineered O-ring energizer, this seal solves the limitations of polyurethane and traditional elastomers. Whether you’re battling abrasive media, high pressure, or corrosive environments, the SPNS seal delivers unmatched performance and longevity.