How to Choose Skeleton Oil Seal?

Skeleton oil seals, also known as radial shaft seals or lip seals, are crucial components used to prevent leakage of lubricants and protect mechanical systems from contaminants like dust, dirt, and moisture. These seals are widely used in industries like automotive, machinery, and manufacturing, and choosing the right oil seal is essential for optimal performance and longevity. Here's a detailed guide to help you choose the correct skeleton oil seal for your specific application.

Read more

 

1. Understand the Application Requirements

 

The first step in choosing a skeleton oil seal is to fully understand the specific application for which it will be used. Factors like operational speed, temperature, pressure, and the type of fluid being sealed are important considerations.

 

- Operating Conditions: Determine the environment in which the oil seal will operate. Consider exposure to extreme temperatures, the presence of chemicals, and whether it will be used indoors or outdoors.

 

- Fluid Type: Identify the type of fluid the seal will be in contact with. This could include oils, grease, or other types of lubricants. Ensure the seal material is compatible with the fluid.

 

- Pressure and Speed: Know the maximum operating pressure and rotational speed of the shaft. Some seals are designed to handle high-pressure environments, while others are suitable for low-pressure applications.

Rubber Skeleton Oil Seal

2. Select the Right Seal Material

 

Skeleton oil seals are available in various materials, each with specific properties that make them suitable for different applications. The choice of material is critical as it affects the seal's resistance to heat, chemicals, and wear.

 

- Nitrile Rubber (NBR): The most common material for oil seals, NBR offers excellent resistance to oil and abrasion. It is suitable for temperatures ranging from -40°C to +120°C and is ideal for general-purpose sealing in industrial and automotive applications.

 

- Fluorocarbon (Viton): Viton seals offer higher resistance to heat and chemicals, making them suitable for high-temperature applications (up to 200°C). They are also resistant to a broader range of chemicals and are ideal for use in environments with aggressive fluids.

 

- Silicone Rubber: Silicone seals offer good flexibility at both high and low temperatures, but they are not as resistant to oil as NBR or Viton. Silicone is often used in applications where temperature resistance is more important than oil resistance.

 

- Polyurethane (PU): Known for its exceptional wear and abrasion resistance, polyurethane is often used in applications where the seal is exposed to high levels of friction and stress.

 

- PTFE (Teflon): PTFE oil seals offer excellent chemical resistance and operate well in a wide temperature range. They are commonly used in applications involving aggressive fluids or extremely high temperatures.

Rubber Skeleton Oil Seal

3. Choose the Right Lip Design

 

The lip design of the oil seal plays a crucial role in how well it prevents leakage and withstands pressure. Skeleton oil seals are available in different lip designs to suit varying applications.

 

- Single Lip (SL): Single-lip oil seals are designed to prevent leakage from the inside of the system. These are commonly used in general sealing applications where there is low pressure and no external contaminants.

 

- Double Lip (DL): Double-lip oil seals have an additional lip that provides extra protection against external contaminants like dust and dirt. These seals are ideal for outdoor applications or where the system is exposed to debris.

 

- Triple Lip (TL): These seals are used in heavy-duty applications where both high pressure and exposure to contaminants are concerns. The additional lips provide a more secure seal and extended durability.

 

4. Consider Seal Dimensions

 

Getting the correct size is essential to ensure a proper fit and effective sealing. Skeleton oil seals are typically specified by their inner diameter (ID), outer diameter (OD), and thickness or width.

 

- Inner Diameter (ID): This is the diameter of the shaft on which the seal will be installed. Measure the shaft accurately to avoid leakage or seal damage.

 

- Outer Diameter (OD): This is the diameter of the bore or housing where the seal will be installed. The outer diameter should be slightly larger than the bore to create a tight fit.

 

- Width: The width of the oil seal should match the depth of the groove or housing where it will be seated. An incorrect width can lead to misalignment and inadequate sealing.

 

It's important to follow the manufacturer&#;s specifications for the proper size. Using calipers or other precise measuring tools can help ensure an accurate fit.

Rubber Skeleton Oil Seal

5. Check for Operating Temperature Range

 

The temperature range that the oil seal will be exposed to is another key factor. If the temperature exceeds the seal's capacity, it can lead to degradation, hardening, or softening of the seal material, leading to premature failure.

 

skf supply professional and honest service.

- Low Temperatures: For cold environments, choose materials like silicone that remain flexible even at low temperatures. NBR seals can handle cold temperatures but are not as effective in extreme cold.

 

- High Temperatures: For high-temperature applications, consider materials like Viton or PTFE that can withstand heat without losing their sealing properties.

 

Always ensure the material and design you select are capable of operating at the upper and lower limits of your application&#;s temperature range.

 

6. Verify Pressure Handling Capability

 

While most skeleton oil seals are designed for low-pressure applications, some seals are specifically designed to handle moderate to high pressure. If your application involves significant pressure levels, be sure to choose an oil seal that can withstand the force without failing.

 

- Low-Pressure Seals: For most general-purpose applications, standard skeleton oil seals can handle low pressures effectively.

 

- High-Pressure Seals: For higher-pressure environments, choose seals with reinforced lips or specialized designs that can handle the extra force.

 

7. Review Shaft Surface and Speed

 

The condition and speed of the shaft on which the oil seal will be mounted directly impact the seal&#;s performance. A worn or rough shaft surface can quickly damage the seal, leading to leakage.

 

- Shaft Surface: Ensure the shaft surface is smooth and free from grooves, scratches, or other imperfections that can compromise the seal. A polished shaft is ideal for maximizing the lifespan of the oil seal.

 

- Rotational Speed: Oil seals are designed to handle certain speeds. High-speed shafts require seals that can withstand the friction generated by rapid rotations without overheating or wearing out quickly.

 

8. Evaluate Dust and Contaminant Exposure

 

If your application is exposed to harsh environmental conditions, dust, or debris, consider using double-lip or triple-lip skeleton oil seals. The extra lips provide additional protection, preventing contaminants from entering the system and compromising the lubrication.

 

For heavy-duty applications, seals with dust flingers or wipers may also be an option to keep contaminants at bay.

 

9. Look for Additional Features

 

Some skeleton oil seals come with extra features designed to enhance performance and durability, especially in demanding applications. These include:

 

- Spring-Loaded Seals: Some seals feature a spring that helps maintain a tight fit around the shaft, ensuring consistent pressure and preventing leaks, even as the seal wears down over time.

 

- Labyrinth Seals: These seals have a unique design that provides extra resistance to contaminants, making them ideal for applications involving extreme dirt or dust exposure.

 

10. Consider the Cost and Availability

 

Finally, when choosing a skeleton oil seal, consider both the cost and the availability of spare parts. While it&#;s important not to compromise on quality, balance your budget with the specific needs of your application. Additionally, ensure that replacement seals are readily available for maintenance purposes.

 

Conclusion

 

Choosing the right skeleton oil seal involves understanding your application&#;s specific requirements, including the environment, shaft speed, pressure, and type of fluid being sealed. Consider the material, lip design, and seal size carefully, and ensure that the seal you select is suitable for the operating conditions. A high-quality, well-chosen skeleton oil seal will ensure efficient operation, extend the lifespan of your machinery, and reduce downtime due to leaks or failures.

 

Find premium O-rings in all sizes and materials. Perfect for industrial sealing. High-quality Seals for various industries.

Modify: Jun. 28,

Skeleton Oil Seal is suitable for many occasions, especially on engineering walking machinery, cranes, fire trucks and mining machinery vehicles with harsh working conditions. It has good sealing performance and mechanical characteristics, and is the main part of shaft sub-seal. Skeleton oil seal is mainly used as sealing material for automobile, sensor, medical, pharmaceutical, valve, pump, sanitation, bearing, electric appliance, rocket, etc. which requires vacuum resistance, friction resistance, high temperature resistance and chemical corrosion resistance.

Automotive Oil Seal

Three forms of Skeleton Oil Seal&#;

1. Closed skeleton oil seal: This kind of Automotive Oil Seal is widely used, but it is inferior to exposed skeleton rotary shaft lip oil seal in terms of positioning accuracy, coaxiality and skeleton heat dissipation. There are two types of oil seal structure types: one is sub-lip type and the other is sub-lip type. It is a stamped metal skeleton wrapped in rubber to become an inner skeleton oil seal. Its manufacturing process is more complicated, but it has good rigidity, easy assembly, and does not require high material of steel plate.

2. Exposed skeleton oil seal: There are two types of structure type of this oil seal: split-flap type and split-flap type. The oil seal has accurate positioning, high coaxiality, easy installation and good heat dissipation of the skeleton. Rubber part and metal skeleton can be processed separately and then glued together to form exposed skeleton type. It is simple to manufacture and cheap. This structure is used in the United States and Japan.

3&#;Assembled skeleton oil seal: oil seal with or without sub-lip and sub-lip. This kind of oil seal is suitable for installation in the rotating shaft end in large and precision equipment. It seals liquids and grease at a pressure not exceeding 0.3 MPa. It assembles a rubber lip, a metal skeleton and a spring ring to form an oil seal. It has an internal and external skeleton to clamp the rubber lip. There is usually a baffle to prevent the spring from falling out.

Since the skeleton oil seal has an oil film between the oil seal and the shaft controlled by the edge of the seal, the oil film has fluid lubrication properties. Under the action of fluid surface tension, the oil film is stiffened just enough to form a crescent-shaped surface at the contact end of the oil film and air to prevent leakage of the working medium, thus achieving a seal on the rotating shaft. The sealing capacity of the oil seal depends on the thickness of the oil film on the sealing surface. If the thickness is too large, the oil seal will leak; if the thickness is too small, dry friction will occur, causing wear of the oil seal and the shaft; if there is no oil film between the seal lip and the shaft, it will easily cause heat and wear.

The company also provides oil seals for Agricultural Machinery, please feel free to contact us if you need!