Oil seal (simering) 12×21×7.5 mm, No name, model Czę001442

Oil seal (simering) 12×21×7.5 mm is a compact radial sealing element designed to prevent lubricant leakage and to keep contaminants out of rotating shaft assemblies. The seal features an inner diameter of 12 mm, an outer diameter of 21 mm and a thickness of 7.5 mm, with a standard single-lip profile suitable for light-duty sealing tasks in small motors, gearboxes, pumps and similar mechanical assemblies.

Advantages

This simering provides a reliable radial seal in confined spaces thanks to its precise dimensional tolerances and single-lip design. Its compact form factor allows installation in small housings while ensuring basic protection against oil loss and ingress of dust and moisture. Because of its simple construction, it is compatible with common shaft finishes and standard installation tools.

Suitable for

• Small electric motors and hobby motors
• Compact gearboxes and transmission assemblies
• Small pumps and fluid-handling devices
• Mechanical assemblies with 12 mm shaft diameter

Key specifications

• Inner diameter: 12 mm
• Outer diameter: 21 mm
• Thickness/profile height: 7.5 mm
• Sealing type: single-lip radial seal
• Typical materials: elastomer sealing lip with rigid casing (material varies by supplier)
• Application: radial sealing for rotating shafts

How to use

Before installation, inspect the shaft and housing bores for burrs, corrosion or excessive wear and clean surfaces to remove old lubricant and debris. Align the oil seal square to the housing bore and press it in evenly using a suitable driver or press tool until it sits flush with the housing face. Apply a thin film of compatible lubricant on the sealing lip and shaft to reduce running-in wear. After installation, verify proper shaft rotation and check for any initial leakage during a short test run.

Usage recommendations

For best results, match the seal dimensions to the shaft and bore tolerances, use seals made from materials compatible with the system lubricant and operating temperature, and avoid excessive shaft runout or misalignment. Replace the seal if the lip shows hardening, cracking or continuous leakage.