Standard Design of Oil Seal: Lip, Housing, and Finish

Standard seal lip designs

Our oil seals come in many different lip designs, some simple and some complex due to their specific applications. However, the most common industry spoken standards are described below.

Single Lip: This design uses a snap-on spring and typically seals the internal media in low pressure applications. The single lip is not recommended for applications where the environment contains dirt or contaminants.

Double Lip: This design is also used with a clamping spring and consists of a primary lip used to seal internal media in low pressure applications. A secondary (also called secondary lip) provides additional protection against dust and dirt.

Dual lip or twin lip: This design consists of a garter spring and two identical primary lips and is typically used to separate two fluids. The space between these two lips must be lubricated with grease or something similar.

Standard Seal Housing Designs

We offer a wide range of housing designs for oil seals, from the simplest to the most challenging applications. The following are some of the most common housing designs used in most sealing applications.

Type A: External metal housing with reinforcement plates for increased structural rigidity. This design is primarily used for shafts over 150 mm in diameter, smaller shafts where additional strength is required, or when used with special rubber compounds.

Type B: Metal housing, mainly used for shafts with diameters up to 150 mm, with bearing housing material in steel or cast iron. This design provides a strong and accurate seal in the housing; however, it may limit the static seal on the outside diameter (OD).

Type C: Rubber-covered metal housing for use with any size shaft. The rubber helps prevent rust and corrosion of the metal and prevents damage during assembly. This design is used for soft alloy, plastic housing materials and is intended for replacement in environments where there is minor damage to the housing surface.

Concrete Mixer Gearbox Oil Seal

Metal Housing Finishes

Oil seals with external metal housings may include a finish or treatment applied to the outer edge to help prevent rust, identify and seal scratches or defects in the housing bore. Common finishes applied to the outer edges of metal OD oil seals include: plain (usually yellow-green adhesive), painted edges, and honed edges.

Oil Seal Style

In combination with the lip and housing types listed above, it is easy to assemble global O-ring and seal (GOR) types, as shown in the following examples.
SC style: single lip with spring, OD
Type TC: Double lip with spring, OD
Type SB: Single lip with spring, metal O.D.
Type TB: Double lip with spring, metal OD
Type SA: Single lip/spring with spring, reinforced metal OD
Type TA: Double lip with spring, reinforced metal OD

Factors for oil seal selection

Type: A combination of lip design and housing type.
Shaft Diameter: the outside diameter of the shaft where the seal will work (sometimes called the inside diameter of the oil seal)
Hole Diameter: the inner diameter of the hole housing where the seal will work (sometimes called the outer diameter of the oil seal)
Width: The depth of the hole. When the width of the seal is not strictly specified, the depth of the hole is usually large enough so that a wider seal can be used instead of the seal.
Seal lip material: e.g. Nitrile, Viton, Silicone, Polyurethane, Teflon.
Any special materials or considerations, e.g. stainless steel for housings and/or springs.
Any special treatments or finishes, such as painted, polished edges, etc.

Steering Power Oil Seal

Honglei is a leading enterprise in China. Our products have been tested by the Center of HEBEI Province Rubber Products Inspection.  Our main product lines include: Automobile oil seal, Agricultural & Construction machinery oil seal, Wheel hub oil seals for tractors, Valve Stem Seals, Precision Rubber Parts, O-rings. Our Products are widely used in coal mines, oil fields, electric power, ships, automobiles, locomotives, construction machinery, agricultural machinery and other industries.

Please feel free to get in touch if you want to buy the high-quality oil seals.