Oil Seal (Lip Seal) Vs. Mechanical Seal: Pros & Cons of Each

Making the Choice of an Oil Seal Vs. Mechanical Seal

When deciding on the best type of seal for a particular application, it is best to consider all aspects of the environment and its purpose. If the application requires a spring- loaded seal, that does not eliminate either the rotary shaft seal or the mechanical seal. If the equipment is operating in extreme temperatures, including situations where the rapid movement of the equipment creates extreme heat, a mechanical seal will hold up better than an oil seal.

Oil seal vs. mechanical seal is not always an easy decision. In some cases, one is the obvious choice because you are replacing a worn out seal with the same type. But in other situations, either type would work and the question is which will enhance productivity the most. At Abbey Seals, we have ample experience with a full range of seal types. We are happy to discuss the specifics of your application and advise you on the optimum type of seal for your equipment. The decision between a rotary shaft or oil seal vs. mechanical seal involves many factors, and we are here to help you make the best choice for your specific needs.

You can find our contact information here or please fill in the product information request form here for information on either type of seal

Their Qualities

Lip seals are made of nitrile, a material that functions well at temperatures of minus 4.4 degrees C up to 135 degrees C. Lip seals have excellent resistance to petroleum and hydraulic oils, and water. They are also very cost-effective. There are spring-loaded and non-spring lip seals, with non-spring lip seals being used for slower shaft processes. With mechanical seals, everyday wear and tear maintenance is reduced because the seals have inboard springs which make them self-adjusting as the faces wear down. Mechanical seals come in different forms depending on the application and the amount of pressure present, as well as the liquid viscosity and temperature. Mechanical seal material may consist of a hard material such as silicon carbide, ceramic or tungsten carbide and matched with a softer material like carbon.

Choosing the correct seal depends heavily on its application and your system needs. At Abbey Seals, we carry out extensive research to ensure we are providing you with durable, safe and appropriate seals for your business needs. We invest in state-of-the-art technology to create custom materials, and Xpress Manufacturing, if needs be. Contact our experts today, and we will be happy to answer any questions you might have about lip seals or mechanical seals.

Replacing a critical component can be difficult to get right, especially if you do not have the original machine specifications. Thankfully, there are a few ways to identify oil seals; from their design, size and material. As there are hundreds of different oil seals available on the market, this guide will cover the four most common design types. Typically available with either a single or double lip, in Nitrile or Viton Rubber Material.

Oil Seal Single Lip vs Double Lip

Firstly, the oil seals covered in this guide classify the single lip as the inner diameter at the bottom of the component. The single lip is vital to the function of the seal by containing the oil, grease or lubricant. The only difference between a single and double lip is the additional rubber lip on the top of the oil seal which helps prevent dust or dirt from coming close to the shaft. Identifying the oil seal lip can be misinterpreted with a visual inspection alone. For or this reason, you should press along the inner diameter at the top of the seal, if you feel a ridge with a slight movement or give it is highly likely you have a double lipped oil seal.

Industry retailers use unique codes to identify oil seals worldwide. The most common lip style designations are 21 (single lip) and 23 (double lip), please read our Oil Seal Cross Reference Guide for more detailed information.

Identify Oil Seal Design

1. Type A - Rubber Covered Lip Seals

Fully covered outer diameter for excellent sealing. This oil seal is fully enclosed in a rubber material and is the most widely used type of oil seal. Great resistance to thermal cycling, temperatures and different chemical resistance.

2. Type B - Metal Outer Diameter Oil Seals

Economic metal outer diameter for standard applications. This is an economical oil seal where the metal is exposed on one side and offers a closer fitting between the oil seal and housing or bore. Due to this, it has limited use with sealing thin liquids or gases.

3. Type C - Reinforced Metal Insert Oil Seals

The same design as type B with an additional inner case for greater structural rigidity. This type of oil seal is typically used in heavy-duty engineering machinery or large diameter sized seals

4. Type F - Stainless Steel Garter Spring

The same design as type A with corrosion protected metal case and stainless-steel garter spring. Suitable for use with a wide range of fuels and chemicals.

Identify Oil Seal Material

Nitrile or NBR is black in colour, whereas, Viton or FKM is usually a brownish colour. To understand the main comparisons between the two compounds read our Nitrile vs. Viton article.

How to Measure Oil Seals

Finally, Polymax part codes follow the same pattern as our O-rings - inner diameter, outer diameter and height. This is different from the industry-standard convention, whereby imperial oil seals follow - outer diameter, inner diameter and height.

We hope the information in this article helps you identify the correct oil seal for your application. If you have any queries feel free to call one of our sales engineers on 01420 482862. Polymax stock over 6,000 oil seals available to buy online, browse our oil seal selection today.