What is a radial lip seal?

A radial lip seal (oil seal) is a sealing element that prevents leakage of lubricant from a bearing housing along a rotating shaft. It consists of a flexible lip pressed against the shaft by a garter spring, a metal case for press-fitting into the housing bore.

How do I select the right seal size?

Seal size is determined by three dimensions: shaft diameter (d), bore/housing diameter (D), and width (b). Standard sizes per ISO 6194 follow preferred number series. The shaft must have appropriate surface finish (Ra 0.2–0.8 μm) and hardness (≥45 HRC).

What is the maximum speed for a standard lip seal?

Standard NBR lip seals work up to a peripheral speed of about 12–15 m/s. FKM (Viton) seals can handle slightly higher speeds. PTFE seals can reach 20+ m/s. The peripheral speed v = π × d × n / 60000 (m/s).

What seal material should I choose?

NBR (Nitrile): -40 to +100°C, mineral oil, general purpose. FKM (Viton): -25 to +200°C, synthetic oils, fuels, chemicals. PTFE: -60 to +200°C, aggressive chemicals, high speed. EPDM: water, steam, brake fluid (not oil-compatible).

Can lip seals handle pressure?

Standard lip seals are designed for near-zero pressure (splash lubrication). For pressures up to 0.05 MPa (0.5 bar), a standard seal may work. Above 0.03–0.05 MPa, use a pressure-rated seal with backup ring or consider a mechanical seal.

Herramienta de ingeniería gratuita

Selección de sellos de eje — ISO 6194

Seleccione sellos radiales de labio según ISO 6194. Ingrese el diámetro del eje, la velocidad y el medio para obtener el tipo de sello recomendado, las dimensiones y el material.

ISO 6194Sellos radiales de labiod × D × b

Recomendación

Sello recomendado (d × D × b)

—

Material

—

Velocidad periférica

—

Verificación de velocidad

—

Tipo de sello

—

Velocidad periférica

Sellos de labio NBR estándar: máx. ~12 m/s. FKM: ~14 m/s. PTFE: ~20 m/s.

Guía de selección de materiales

NBR (Nitrilo): -40 a +100°C. Aceite mineral, grasa lubricante. Uso general. El más común.

FKM (Viton): -25 a +200°C. Aceite sintético, combustibles, alta temperatura. Opción premium.

PTFE: -60 a +200°C. Productos químicos agresivos, alta velocidad, funcionamiento en seco.

EPDM: -50 a +150°C. Agua, vapor, líquido de frenos. NO compatible con aceite mineral.