What is TC Oil Seal?

TC oil seal is a rubber-coated skeleton oil seal with a double lip structure. It is mainly used to isolate lubricating parts and output parts in mechanical transmission systems to prevent lubricating oil leakage and has dust-proof function.

Definition and core functions of TC oil seals

TC oil seals are a representative form of skeleton oil seals. They belong to the inner-wrapped skeleton oil seals. The "T" in its name represents the double lip design (main lip for oil prevention and auxiliary lip for dust prevention), and the "C" represents the external rubber coating material. It completely covers the metal skeleton with rubber and is equipped with a self-tightening spring to form a sealing structure. It is widely used in the sealing of rotating moving parts.

Core function‌

Oil and dust prevention‌: The main lip prevents lubricating oil leakage, and the auxiliary lip blocks external dust from entering, which is suitable for dusty environments.

Isolation of lubricating parts‌: Isolate the parts that need to be lubricated (such as bearings) from the output parts (such as shafts) in the transmission system to ensure the stable operation of the lubrication system.

Structural and material characteristics

Structural design

Double-lip structure (main lip + auxiliary lip) and metal skeleton enhance sealing performance. The skeleton is similar to the steel bars in concrete, maintaining shape and tension.

Built-in spring provides continuous self-tightening force to adapt to high pressure or corrosive environment.

Common materials

Rubber materials include nitrile rubber (NBR, low-cost oil resistance), fluororubber (FKM, high temperature corrosion resistance), etc. Fluororubber or perfluoroether (FFKM, temperature resistance up to 320℃) should be used in high temperature environment (>150℃).

Application scenarios and selection points

Typical applications

TC oil seals are the most commonly used oil seal types in industry, suitable for environments with pressure ≤0.3bar, such as automotive transmission systems, pumps and valves and other rotating equipment.

Selection considerations

Environmental factors: Double lips (TC type) are required when there is a lot of dust, and single lip (SC type) can be selected in dust-free environment.

Corrosion resistance requirements: If the environment is highly corrosive, the fully rubber-covered TF type (higher cost) should be selected.

Comparison with other oil seals

Difference from PD type: PD skeleton oil seals are usually low-speed ordinary types, while TC type emphasizes double-lip sealing and is more suitable for high-speed or complex environments.

Difference from TF/SF type: TF/SF is a fully covered iron shell type, which is expensive and dedicated to corrosive environments, while TC type is more versatile.

TC oil seals have become the mainstream choice in mechanical seals due to their double-lip design, material diversity and high adaptability, especially in scenarios where oil and dust protection are required.