Why is Oil Seal Wholesale Better?

Whenever I buy seals from Stihl, they're always TB seals. Whenever I buy seals from the local seal supplier they're always TC. Besides the obvious that one is metal outer and the other is rubber coated metal - for the application in OPE, is there any real advantage of one of the two designs?

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Whenever I buy seals from Stihl, they're always TB seals. Whenever I buy seals from the local seal supplier they're always TC. Besides the obvious that one is metal outer and the other is rubber coated metal - for the application in OPE, is there any real advantage of one of the two designs?

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Tom I like the OD rubber coated one due to the positive sealing
quality of the seal pocket to seal interface of the neoprean I'm wondering this same issue too. My current project old Jonsered 535 had TB style oil seals and the ones I managed to buy are TC.
The reason for TB may even be easier or more forgiving installation during saw manufacturing process. Rubber coated ones you can not just hammer in, you got to have suitable tool to press them in evenly. Just my wild guess though.
What comes to other properties these rubber coated types are used in 2 stroke motorbikes with double HP per CC so I do not see an issue there either. Future will tell...

Any decent bearing, belt and seal company should be able to get you either version.
Having said that, I've seen both versions from the oem, especially on clam shell models. The tc seals better and takes bore deflection thrn thr to style. In reality you shouldn't need any sealant on any seal, even though most (including myself) tend to give the od a little smear for insurance.

It's been such a long time since doing a clam shell and got OEM seals that I totally forgot that they had rubber coating, thanks for the reminder. Rubber coatings tend to harden or even shrink over time. They are easier to press in with less effort because the rubber deforms, I can often push them in with my bare hands. The rubber coated versions seal better in spots that have some corrosion, scratches, oil sludge, carbon buildup etc. I prefer this style for replacement when the engine or transmission is not disassembled, washed or being unable to use a proper seal driver or press.
Meatal clad seals are the stronger longer lasting version, they are less likely to pop out and seal better against the case by a stronger interference fit with the drawback of metal corrosion or dissimilar metal reactions if the seal coating is damaged. You should use a properly sized installation driver or press to install these straight and to the correct depth without distorting the seals outward metal face or the sealing lip will be distorted.
Some like to use sealants, I do not because the sealant may not bond to the case or the seal creating a leak, the sealant may not expand/contract at the same rate as the rubber or metal seals exterior causing a leak or even seal movement/looseness/dislodging. Lock tite for seals may be used to help overcome case damage or bore size irregularities to the available seals, thankfully I have not yet needed to use this personally...but life throws curveballs at every at bat it seems. The ability of a sealant to bond may have zero bearing on performance.
Teflon tape is a common "sealant" which bonds to absolutely nothing but is vital to the assembly of so many fittings.
RTV is the complete opposite, you might catch me "tooling" it in with a bit of emery cloth to guarantee adhesion.
In general, I prefer TB to TC, since seeing a few TC types which could be spun in the bore. Then again, they were quite old and tech has moved.
I'm surprised no one has brought up the types of 'rubber' listed by OP, as the properties vary so widely.

The ability of a sealant to bond may have zero bearing on performance, Teflon tape is a common "sealant" which bonds to absolutely nothing but is vital to the assembly of so many fittings. RTV is the complete opposite, you might catch me "tooling" it in with a bit of emery cloth to guarantee adhesion.
In general, I prefer TB to TC, since seeing a few TC types which could be spun in the bore. Then again, they were quite old and tech has moved.
I'm surprised no one has brought up the types of 'rubber' listed by OP, as the properties vary so widely.

I have only used Viton and nitrile.

Different Types of Oil Seals

You can find more information on our web, so please take a look.

Are you looking to keep your machinery free from any unwanted leakages but aren't sure which rotary shaft seal is right for your needs? This guide will provide you with everything you need to know in order to select the right one for your application.

Oil seals, which are also known as rotary shaft seals, fluid seals or grease seals, play an important role in closing down the gaps between moving and stationary elements of mechanical equipment.

By preventing lubricants from escaping, they protect key components of machinery from being damaged by leaks of various fluids. Everything from car engines to assembly machines use these oil seals to remain free from any harmful interactions that can cause serious and expensive damage to any of their critical parts.

There are a wide range of oil seals to select from for any number of uses, so this guide will break down the most common seals to help you choose the right one for whatever piece of machinery you are working on.

What are rotary shaft seals?

Rotary shaft or oil seals are placed between moving and stationary pieces of machinery to ensure that contaminants, moisture, corrosive materials and abrasives do not damage the various components. They can also prevent unwanted mixing of fluids, including water and oil combining within a machine.

How are Oil Seals made?

First, an elastomer, most often nitrile, is vulcanised to a metal ring. This creates a stiffening effect that includes a specialised metal tension spring directly behind the sealing lip, keeping the oil seal firmly in place against the moving part.

Oil Seal Materials

There are many different materials used to manufacture oil seals.

Leather Oil Seals - Leather Seals, also known as Type L Oil Seals, are most common in components that are subject to dirt and poor lubrication. Since they come pre-lubricated and are able to absorb fluids, leather oil seals are able to provide sealing properties in conditions that synthetic rubber is unable to.

Synthetic Rubber Oil Seals - Styrene Butadiene Rubber oil seals, or just SBR oil seals, offer strong resistance to abrasions and lesions, making them an ideal seal for fast-moving machinery. With the ability to withstand extreme temperatures with its heat-aging qualities, they can be used in outdoor components. They are also seen as more cost-effective oil seals than natural rubber.

Nitrile Oil Seals - Nitrile oil seals, which is the commonly used term for acrylonitrile-butadiene rubber seals, is a very good general-purpose option due to the flexibility of use across a variety of components. The resistance is strong against fats, hot water, gasoline, mineral oils, grease and animal oils, making them the most often-used oil seals. They do not have a wide temperature range, making them a poor choice for machinery that can see extreme changes in temperature.

Viton Oil Seals - A synthetic rubber and fluoropolymer elastomer, Viton is used to make oil seals that provide resistance in both high temperature, up to 250°C and low compression set components. They also offer a high resistance to chemicals and abrasions, so they can be used in elements that regularly interact with petroleum and solvents.

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Polyacrylate Oil Seals - Mostly selected for automotive and transmission uses, polyacrylate seals are able to withstand fuel, oil, ozone, sunlight and weather when used. With cars exposed to all these different fluids and elements, they are the perfect choice. However, they should not be used in low temperatures, as their flexibility weakens when cold.

Silicone Oil Seals - Designed to absorb lubricants in order to lessen wear and friction, silicone rotary shafts also offer high thermal resistance and a large temperature range. But, they do not handle abrasions well or interact with oxidized oils.

PTFE Oil Seals - A relatively new and exciting oil seal, the use of polytetrafluoroethylene means that they can withstand dry or unlubricated operations. With a massive thermal range of  -130ºC to +200ºC and a strong resistance to chemicals, they are considered to be the future of rotary shaft seals.

How to Choose the Right Oil Seal

There are several key factors to consider when you are selecting the oil seals for your next project to ensure that you protect your machinery from immediate and long-term damage.

Pressure - Many oil seals can only withstand low-pressure applications, so understanding the compression set of your components is key.

Temperature - Just like pressure, the temperature that your oil seal will be operating in must be known so that you can choose one that can withstand the heat or cold. PTFE have the widest range of temperature, making them useful for machines who can see usage in extreme weather or elements.

Shaft Speed - Considering the speed that the shaft will be moving, the runout, the housing bore and the type of oil being sealed is vital to making sure you select an oil seal that will not suffer from abrasions or spiralling.

Fluid Types - Various oil seals are able to withstand interactions with oils, fuels, grease, water and more. Knowing what type of fluid the rotary shaft seal will be in constant contact with will ensure the longevity of the seal and surrounding components.

Lubricant Amount - Seals will always perform best when lubricated, however in some machines there are more likely to be dry spells. For these cases, selecting a leather or PTFE seal will be beneficial, as both can operate with less lubrication than others.

If you require any assistance in discovering the factors that lead to the right oil seal choices, the Simply Seals Team is happy to assist you!

Find the right Oil Seal for your needs with Simply Seals!

With dozens of specifically-designed oil seals made from a variety of materials, it can be very difficult to understand the best choice for their machinery.

That is why the Totally Seals team is always available to assist you with choosing the correct style, material, and size of oil seal for everything from commercial machinery to hobby car building.

For more information, please visit Oil Seal Wholesale.