Spring-energized seals PTFE
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Spring-energized seals are singleacting sealing elements primarily used for sealing reciprocating pistons and rods. Other uses include rotary, swiveling and static applications. The seal consists of two components: • an outer sealing element made of high-strength plastic (e.g. PTFE, PE-UHMW) • and an integrated spring (e.g. high-grade/stainless steel, Hastelloy®(3) and Elgiloy®(3)) Benefits • Outstanding dry-running characteristics • Low wear • Low friction • Variable friction conditions through choice of spring characteristics • Extremely low breakaway forces even after prolonged down...

Application Examples Piston pump in liquid chromatography equipment up to 300 bar for different chemical media and substances. High-pressure axial piston pump for cleaning equipment up to 280 bar of water pressure and cleaning additives. Spring-energized seals are used in a wide range of industrial applications: • Automotive industry, e.g. direct fuel injection systems • General manufacturing/ mechanical engineering, e.g. CNC machines, compressors and vacuum pumps as well as tank systems • Aerospace industry, e.g. in landing gear systems • Food processing industry, e.g. in packaging...

Automotive Industry Mechanical Engineering Painting Technology Piston pump for media separation of gasoline/ engine oil in gasoline direct injection system. CNC machine turret serving as rotary transmission for coolant/lubricant pressures up to 80 bar and as bearing seal. Valve needle seal for paint pressures up to 20 bar; special seal geometry and special PE compounds ensure long service life and good wiping effect. Seal Design and Action Principle 1 � Plastic casing with high thermal and chemical resistance � Stainless steel spring for defined sealing forces � Sealing lips � Back of seal...

Preferential Range With sharp-edged sealing lip on = Seal type “Rod Seal“ the internal diameter for good wiping 332 effect with rod seals. HS 21059 = Casing material (for other compounds see compound table Installation Dimensions Additional diameters/sizes from 2 mm to 3000 mm available on request.

Preferential Range = Type, “Piston Seal” With sharp-edged sealing lip on good wiping effect with rod seals. HS 21037 = Casing material (for other compounds see compound table = Spring material (see page 29) Additional diameters/sizes from 2 mm to 3000 mm available on request. Installation Dimensions

Standard Type URF Preferential Range Ordering example: URF – B20 – 108 – HS 21037 – C URF = Seal type “Shaft Seal“ HS 21037 = Casing material (for other compounds see compound table URF – Shaft and Rod Seal = Spring material (see page 29) With clamping flange for sealing rotary and swiveling applications. Operating Limits (1) T = –75 °C to +300 °C p = up to 200 bar v = 15 m/s � m Installation Dimensions Additional diameters/sizes from 2 mm to 3000 mm available on request. Flange Ø Groove Lead-In Chamfer F H 11 Width G1 min G2–0.1 K Ø B + 6,5 2,4 0,70 0,6 Ø B + 8,5 3,6 0,85 0,8 Ø B + 12,0...

URS – Piston and Rod Seal | Shaft Seal CRS – Piston and Rod Seal | Static Seal For gaseous media. Chamfered sealing lip with large wear Very good sealing performance with reserve; even with rotary and swiveling high pressures. Static sealing action and/or for slow-moving applications.

URV Rod Seal | Shaft Seal For fluids. With shortened, sharp-lipped interior sealing lip for good wiping effect; also suitable for sealing rotary and swiveling applications. CRV Rod Seal For fluids. With sharp-edged interior sealing lip for good sealing effect with high pressures; very good wiping effect. Piston and Rod Seal For critical fluids (paint, lacquers, gasoline, etc.). Double sealing edge for improved sealing performance. Rod Seal For separating two media. Groove seal with integrated memory sealing lip.

For extra-large installation dimensions. Rod Seal | Shaft Seal With O-ring as static seal. Very good static sealing effect at the external diameter and/or with rough housing surfaces. Piston and Rod Seal For high pressure loads with special design and reinforced back of seal. Rod Seal (Could also be designed as a piston seal.) For separating two media. Complete Piston/Complete Package Benefits: Solution • One-part piston Design available on request. • Replaces metal piston by plastic piston • Ready-/easy-to assemble versions with favorable cost-benefit ratio • No damage to seals...

Standard Version UAI for internal pressure (left). UAA for external pressure (right). Rotary seal for rotating and swiveling motions. Operating Limits T = -75 °C to +300 °C p = up to 250 bar v = 2.5 m/s (X Standard Version CAI for internal pressure (left). CAA for external pressure (right). Rotary seal for rotating and swiveling motions. Operating Limits1 T = -95 °C to +300 °C p = up to 700 bar v = 0.5 m/s Special Version Internal pressure (left). External pressure (right). Rotary seal for rotating and swiveling motions.

To assure that the sealing lips are permanently pressed against the contact surfaces, spring-energized seals made from PTFE and PE compounds require metal spring elements that are integrated in the plastic casings. In special cases, these may be elastomer O-rings as well. Most seals, however, have metal springs. The spring assures constantly even contact pressure of the sealing lip across the entire temperature range. For the different types of seals different types of springs are available with particular spring characteristics. These spring characteristics and properties have a...

Technical Details Spring Characteristics This map shows the various spring characteristics Purpose-manufactured special springs for related to the individual nominal cross-sections, clearly friction-optimized seals assure minimum contact revealing the differences between U-, V- and/or pressures with large rates of spring travel. C-springs. This data based on a 20 mm length of spring. This enables us to make pinpoint calculations and proposals for seals offering high wear reserves and thus prolonged service life. Vergleich U-Federn mit C-Federn U-Spring compared to C-Spring (2) spring force...