AVAILABILITY
A sampling of Parker’s part numbers are shown in the configurator above for select materials and sizes. If the material and dimensions required are not shown, assistance with part number configuration may be found in the literature documents in the Product Support tab. To check current tooling, review the Part Number Look-up document. Contact Parker for requirements outside typical ranges.

PERFORMANCE ADVANTAGES
Parker’s HS Profile is a viable alternative to conventional O-ring and back-up ring combinations for static sealing applications at high pressures. The HS profile was developed for mobile equipment OEM’s as they continue to consider warranty costs and losses due to down time related to cylinder head glands. Two of the most common seal failures on cylinder heads are O-ring back-up blow-out and pinched back-ups. Both failures are common in systems with high eccentricities or large extrusion gaps. The robust one-piece symmetrical seal geometry of the HS Profile features dual high-concentration contact points for increased sealing and stability. Extrusion-resistant Parker polyure¬thane compounds not only simplifies installation but also enhances the sealing effect in pulsating pressure conditions. As a result, service life is significantly extended.

Compared to conventional multi-piece O-ring and back-up combinations, the HS Profile offers the following advantages:
• Easy installation and elimination of worry over incorrect placement of an O-ring and back-ups which can become pinched, folded, or broken during installation
• Greater stability
• No twisting or rolling in the groove
• High extrusion resistant polyurethane materials
• Longer service life

HS Profile part numbers correspond to dimensions and tolerances of standard AS568 O-ring sizes for single back-up O-ring groove widths.

Standard Materials:
• P4700A90 Polyurethane; Temp -65 / +200F; Pressure 10,000 psi static

Alternate Materials: For applications that may require an alternate material, please contact your Parker EPS representative.

Typical applications:
• Static sealing of hydraulic valves, cylinders, machine tools, injection molding machines and any static sealing point requiring radial sealing

Polyurethane Head Seals for High Pressure Hydraulic Applications (HS)