Oil Seal VB - Rotary Shaft Seal

What is a VB Oil Seal?

When and Where is the VB Oil Seal Used?

The VB oil seal is selected for applications where reliable grease sealing, minimal wear and a low-friction design are priorities. Because it is a springless oil seal, the lip operates with lower and more consistent contact pressure than seals with a spring or dual lip, reducing friction during operation. This makes the oil seal VB particularly suitable for electric motors, fans, small gear reducers, transmissions and various industrial drive systems where smooth, efficient rotation is desired. In closed mechanical housings. such as gearboxes, bearing carriers or internal pump compartments, the VB oil seal effectively retains grease and oil without requiring increased sealing pressure to keep the lip stable. The metal outer diameter also contributes to a firm, accurate press-fit and excellent shape stability, especially at larger diameters or in applications where vibration may occur.

Construction and Material Options

A VB oil seal consists of a metal outer case that is pressed securely and dimensionally stable into the housing, combined with an elastomer sealing lip that dynamically seals against the rotating shaft. This construction provides a stable and durable sealing function, especially in clean environments where a metal-cased oil seal must maintain its geometry for long periods without deformation. The sealing lip is typically made from NBR for standard oils, greases and general industrial lubrication, while FKM is chosen when the seal is exposed to higher operating temperatures or chemically more aggressive lubricants. In applications requiring improved ozone or weather resistance, CR can be used, whereas EPDM is selected when compatibility with brake fluids, water-based media or certain synthetic lubricants is required. For more demanding or specialized environments, ACM or HNBR may also be applied, for example when enhanced heat resistance, ozone resistance or compatibility with modern synthetic fluids is essential. Because the design is completely springless, the profile remains slim, generates less heat and provides a low-friction sealing function that is especially well-suited for equipment operating continuously and at consistent speed.

Material Table

Performance, Advantages and Limitations

The biggest advantage of the oil seal VB is the low friction, that’s what makes this rotary shaft seal VB type suitable for rotating shafts which must rotate smooth and energy efficient. Because the lip has no spring load, less heat builds up at the contact surface, which is especially beneficial for continuously rotating shafts or higher speeds. The metal outer diameter helps maintain a stable positioning, precise interference fit and high dimensional stability, which is essential to machines where vibrations or temperature changes are present. Because the sealing lip functions purely through material elasticity, it wears more slowly and, provided proper lubrication is maintained, remains reliable for long service periods without noticeable performance loss. The trade-off of this springless design is that a VB oil seal is not suitable for pressure, tolerates only limited shaft misalignment and is more sensitive to contamination than designs with a dust lip. For that reason, the oil sealVB is primarily used as a grease seal in clean or internal housings where the operating environment can be controlled effectively.

Typical Applications of VB Oil Seals

VB oil seals are used across a wide range of machinery where grease or lubricant must be retained effectively without requiring a spring-loaded sealing mechanism. They are commonly applied in electric motors, small gearboxes, industrial pumps, internal transmission components, fans, generators and various mechanical drive assemblies where a stable, low-friction seal is required. VB oil seals also appear in agricultural machinery and mobile equipment, particularly in protected internal sections where contamination is limited. In all these applications, the low heat generation, high dimensional stability and structural rigidity of a metal OD oil seal provide clear advantages. Especially when installed behind an additional barrier, such as a bearing cover, dust cap, V-ring or labyrinth seal, an oil seal VB can operate reliably for many years without performance loss, since the combination of protection and low friction significantly extends its service life.

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