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Oil seals are found in a wide range of applications, in virtually every industrial sector. It is essential to select the correct oil seal so that the application in which it is used can run efficiently, free of leaks or other issues. In this blog, we explain which factors you should pay attention to when selecting the best oil seal for your application.
The group of oil seals used in dynamic applications include radial shaft seals that seal a rotating shaft around its circumference. They are also known as lip seals, but in this blog we will use the term oil seals.
Usually, these oil seals are used to seal lubricating oil or grease and contain it within the application, so that moving parts such as bearings are continually supplied with enough lubrication. However, such seals are also used for sealing other liquids, gases, and solids, such as powders or granules.
An oil seal consists of:
The lip is specially designed to ensure the oil seal works effectively with the different forces that arise during rotation. Many different designs and materials are used, so countless types of oil seals are available. These are chosen according to the application; pumps, gearboxes, wheels, and many other rotating applications where fluids need to be sealed. They are used in a variety of sectors, such as the chemical industry, manufacturing, wind turbines, automotive sector, food industry, and more. Oil seals are used in nearly all sectors.
What should you take into account when selecting an oil seal? Different types of oil seals and various types of materials are available, each designed for specific uses. It is also important to select the right size of oil seal for the best results. For this reason, selecting the right oil seal requires adequate understanding of the application in which it will be used.
Most standard oil seals have to comply with the DIN and ISO standards. Different standard types of oil seals are available that comply with these requirements.
The most common oil seals are the ERIKS types R, RST, M and MST, which correspond respectively to types A, AS, B and BS according to DIN /ISO .
DIN
Standard /
ERIKS
DIN
A
Standard /
Rubber covered
ERIKS
R
DIN
AS
Standard /
As type A with dust lip
ERIKS
RS
DIN
B
Standard /
Metal cased design
ERIKS
M
DIN
BS
Standard /
As type B with dust lip
ERIKS
MS
DIN
C
Standard /
Double metal cased
ERIKS
GV
DIN
CS
Standard /
As type C with dust lip
ERIKS
GVST
All are fitted with a spring to preload the sealing lip. All these types are for non-pressurised or low-pressure applications up to 0.5 bar for diameters of a limited size. For diameter of 500 mm or more, the maximum pressure is 0.1 bar. For higher pressures, special types or PTFE lip seals can be used.
ERIKS type M (type B according to the DIN standard) has a single metal casing and rubber sealing lip. Since the casing is made of metal, it must be fitted in a well-finished, undamaged groove. Large volumes of oil seals with metal casings are often cheaper, which is why they are often used as original equipment in machines. However, if an oil seal has to be replaced, types with a rubber exterior (type R or RST) are easier to fit. Type MST is similar to M and commonly used. The difference is the dust lip in the MST oil seal that prevents dust and dirt reaching the sealing lip, and extends its service life in dusty environments.
ERIKS type GV (type C according to DIN) is equivalent to type M, but is a heavy-duty version with a double metal casing. This can be a useful solution with larger diameters in more demanding applications. There is also a version of this type with a dust lip; the GVST (type CS according to DIN).
ERIKS type R (type A according to the DIN standard) is identical in shape to type M, but has a rubber outer case with metal reinforcement on the inside. The rubber creates a good seal in the housing, even if the housing has suffered minor damage or is not in its best condition for other reasons. The RST version has a dust lip. These types are often chosen to replace a type with a metal outer case because they are easier to install and can cope with minor damage to the groove, such as scratches.
ERIKS also supplies the types GR and GRST. These are virtually identical to the types R and RST, except in this case the metal inner ring is also completely encased in rubber. ERIKS uses FKM rubber here as standard, so these seals are ideal for use in acidic environments.
An overview of the different standard types of oil seals and their main characteristics is shown below.
In addition to these standardised types, the following special types are also available:
These are comparable to type R and RST, except the outer case does not have a metal reinforcement ring. To compensate, the outside is not made of normal rubber, but a hard, heavy-duty rubber fabric. The advantage is that these types can be made in a split version. They are almost always produced to order, and made of NBR or FKM.
These types are made with a metal outer case and a PTFE lip. They are suitable for a wide range of temperatures from -90 °C to +260 °C.These lip seals can also be used for higher pressures of up to 10 bar (special types up to 25 bar) and rotational speeds of up to 40-45 m/s. Certain grades of PTFE are suitable for use in pharmaceutical and food applications. One important point is that PTFE lip seals do require a shaft with a harder, smoother finish.
Cassette seals are designed to maximise grease or oil retention and protection against liquid or solid contaminants. These seals are provided with their own bushings in which dirt is kept out and oil/grease kept in by a multi-lip seal.
These cassette seals are widely used in wheel-end applications, such as the axles of agricultural machinery or off-road trucks.
The sealing lip of the RST-D is more heavy-duty, so it can cope with pressures of up to 10 bar at slightly lower rotation speeds.
Reinforced GVP design for larger diameters, with rotation speeds of up to 15 m/s and pressure of 3-4 bar
Outer case
The metal used in the outer case of oil seals is usually made of carbon steel. Upon request, and depending on quantities, a different type of steel (such as stainless steel) can be used.
The quality of the rubber or rubber fabric used to make an outer case is the same as the quality of the rubber sealing lip. Fabric reinforced rubber is, as the name suggests, rubber reinforced with a fabric.
Spring
Standard springs are made of carbon steel. We use stainless-steel springs for our GR and GRST oil seals made from FKM rubber. In some rare cases, an O-ring is even used as a spring element. Standard PTFE lip seals are not fitted with springs.
Sealing lip
The sealing lip is always made of a rubber or synthetic material. For oil seals with a rubber outer case (R, RST, GR, GRST), the rubber quality of the sealing lip and the outer case are the same.
The material of the sealing lip is chosen according to the liquid to be sealed and the rotational speed. For larger shafts, an NBR sealing lip can cope with surface speeds of up to 10-12 m/s, while an FKM lip is suitable for speeds of up to 35-38 m/s.
Nitrile Butadiene Rubber (NBR, nitrile)
NBR, also known as nitrile rubber or nitrile, is the most popular material for an oil seal because of its good resistance to many oils and greases, such as mineral grease and hydraulic oil. Depending on their composition, synthetic oils and greases, such as those based on glycol, can damage NBR rubber materials. Depending on the amount of glycol, a PTFE lip seal may be the best choice. NBR is also unable to cope with contact with acids and solvents. The rubber is suitable for oil and grease at temperatures from -35 °C to 100 °C.
Most ERIKS oil seals, such as the types M, MST, R and RST, are made of NBR as standard.
Fluorine rubber (FKM, Viton&#;)
FKM or FPM, which is in well-known brand Viton&#;, can withstand higher liquid temperatures of up to 180 ˚C. FKM is highly resistant to strong acids and bases, as well as to synthetic oils and greases. Glycol-based oil and grease, however, can also damage FKM.
Because of the higher temperature resistance of FKM, this material is also chosen for applications where higher speeds play a role, which raise the temperature at the sealing lip considerably. Usually, using FKM will result in a longer life than using NBR. This compensates the higher price of FKM compared to NBR, as an FKM does not have to be replaced as frequently. The low temperature resistance of standard FKM is limited to -15 ˚C.
Polytetrafluoroethylene (PTFE, Teflon®)
PTFE, which is used in the well-known brand Teflon®, is less commonly used, but it is the preferred material for specific rotating seals in the chemical, food and pharmaceutical industries. This material is notable for having a very low frictional resistance and the best chemical resistance. It can also withstand a very wide range of temperatures in these types of seals; -80 ˚C to 200 ˚C. The shafts on which oil seals with PTFE lips are used require a harder and finer finish. Something like an axle sleeve can also be used to meet this requirement.
EPDM
EPDM oil seals are less common. They are used in solvent, hot water and steam applications, EPDM resists low temperatures down to -50 °C and UV radiation well. Some types of EPDM are also suitable for higher temperatures up to +150 °C. EPDM oil seals are usually available upon request.
VMQ (silicone)
VMQ, also known as silicone, is also used for oil seals, but this is less common because the mechanical strength of VMQ is low and this material has poor wear-resistance This makes it less suitable for dynamic applications, but it can withstand fairly low and high temperatures from -60 °C to 200 °C. Many types of VMQ are also suitable for contact with pharmaceutical and food products, so VMQ is an option worth considering. VMQ oil seals are usually available on request.
Rubber type
Material Code ISO
Heat resistance
Rubber type
Nitrile
High wear resistance good running properties for general use
Material Code ISO
NBR
Heat resistance
-35 °C to + 100 °C
Rubber type
Polyacrylate
Better heat, oil and chemical resistance than NBR
It is recommended for use in oil which contains load bearing additives such as EP gear oils
Material Code ISO
ACM
Heat resistance
-20 °C to + 130 °C
Rubber type
Viton®
High level of chemical resistance
High temperature resistance
Material Code ISO
FPM
Heat resistance
-15 °C to + 180 °C
Rubber type
Silicone
Wide temperature range
Commonly used in low temperature applications
Very prone to mechanical damage during fitting
Material Code ISO
MVQ
Heat resistance
-50 °C to + 150 °C
Rubber type
Polytetrafluoroethylene
Chemical resistant
Low coefficient of friction poor elastic properties not wear resistant if used by dynamic applications
Material Code ISO
PTFE
Heat resistance
-80 °C to + 200 °C
Rubber type
Leather
Recommended for abrasive applications
Good running properties, due to the impregnated seal lip
Can be used on shafts which have a surface roughness outside the range for rubber seals
Not suitable for water
Material Code ISO
-
Heat resistance
-40 °C to + 90 °C
Oil seals are available in an immense range of sizes, for shafts from a few millimetres to several metres. Once the shaft diameter, groove diameter (housing diameter) and groove width are known, selecting an appropriate oil seal is a simple task. An oil seal or its product description is usually associated with three dimensions, for example 6x15x4. These refer to the sizes of the hardware for which the oil seal is designed. In this example, this oil seal is suitable for: 6-mm shaft diameter x 15-mm groove diameter x 4-mm minimum groove width.
Have you found the right oil seal for your application? The next step is fitting the oil seal correctly, so that it remains undamaged.
Before fitting the oil seal, it is essential to check that the oil seal, shaft and bore are clean and undamaged. The surfaces the oil seal will come into contact with must be free of sharp points or burrs. The sealing lip is fragile, so even minimal damage can cause a leak. It is also important that the shaft and bore are correctly finished.
To install an oil seal properly, the shaft must be undamaged. This is so the oil seal can do its job properly on the one hand, and to prevent it from being damaged during fitting on the other. In addition, it is very important to lubricate the shaft, the sealing lip and the bore with plenty of grease. This will allow the oil seal to slide more easily over the shaft and prevent dry running after the first rotation. The oil seal may also come into contact with the keyway, thread or other grooves when sliding over the shaft. By taping or covering the shaft at the location of these irregularities with oil-soaked paper, the oil seal can be mounted without damage to the sealing lip.
Other important factors are ensuring the hardness and roughness of the shaft are correct. A shaft hardness of HRC 45 is recommended for a rubber sealing lip, with a roughness of Ra 0.4-0.8. A higher shaft hardness of HRC 60 and shaft roughness of Ra 0.1-0.4 is recommended for a PTFE lip.
Always start by making sure the oil seal is facing the right direction. The oil seal must be positioned with its spring to the side of the medium to be sealed. The oil seal must then be pressed into the bore. It must fit tightly (H8 in the groove is recommended). Use appropriate tools for this, such as an impact socket set, to ensure that the force is applied evenly during pressing. The oil seal must never be hammered into the bore with brute force, but eased in.
See here for more information and useful fitting tips.
Stijn de Cnop
Product Manager of Sealing & Polymer TechnologyProduct Manager of Sealing & Polymer Technology
Product Manager of Sealing & Polymer Technology
An oil seal is a type of seal used in various industrial equipment to close the gap between its moving and non-moving components. These oil seals help prevent lubricant leakage at high pressures and block foreign components from entering the machinery. With such an important role to play, these oil seals must be chosen carefully. This post discusses the types of oil seals and also guides you through the important factors to choose an appropriate oil seal for your industry.
Types of Oil Seals &#; Based on Materials
There is a wide range of seals to select according to the type of material. Some of the types of oil seals are as follows:
Rubber seals are the most common types of sealing solutions preferred for tight sealing. Rubber seals are corrosion resistant and are used in both high and low-pressure applications. Nitrile, polyacrylate, Viton®, silicone, and polytetrafluoroethylene are a few common types of rubber materials used for this purpose. Each material possesses the typical capability, so, you must choose the rubber material carefully for your application.
Rubber seals are the most common types of sealing solutions preferred for tight sealing. Rubber seals are corrosion resistant and are used in both high and low-pressure applications. Nitrile, polyacrylate, Viton®, silicone, and polytetrafluoroethylene are a few common types of rubber materials used for this purpose. Each material possesses the typical capability, so, you must choose the rubber material carefully for your application.
These seals feature stamped metal cases with an elastomer bonded sealing lip. Carbon steel is the metal used for making the case. The case protects the lip seal during installation. Metal encased seals are generally used for high-pressure or high-temperature applications.
These seals feature stamped metal cases with an elastomer bonded sealing lip. Carbon steel is the metal used for making the case. The case protects the lip seal during installation. Metal encased seals are generally used for high-pressure or high-temperature applications.
These seals possess good running properties and are generally preferred for abrasive applications. The seals are usually used for shafts that possess surface roughness higher than rubber seals.
These seals possess good running properties and are generally preferred for abrasive applications. The seals are usually used for shafts that possess surface roughness higher than rubber seals.
7 Important Factors to Consider When Choosing Oil Seals
With varieties of seals available, choosing the right seal for application can be a daunting task. The following factors will help make the right selection.
In addition to the above-given factors, sourcing high-quality seals from a trusted manufacturer are quite important. SSP Seals provides high-quality oil seals for industrial applications in automotive, oil and energy, and other sectors. The company can provide seals made of a wide range of materials including PTFE, Viton, Silicone, Nitrile, and so on.
Oil seals (also known as rotary seals or shaft seals) cover a wide range of applications ranging from domestic equipments to automotive and power plant machinery, industrial pumps, gas and aircraft turbines and compressors.
If yours is a modern system, the surface speed can go up to 30 m/s and operating temperature can be as high as 250 degree Celcius. For these type of oil seals, our general purpose high performance oil seals can be employed. When the speed is increased up to 90 m/s, the lip will be produced using PTFE based compound to reduce heat generation. For high pressure applications, we offer a wide range of oil seal profile made using PTFE based compounds.
Here at Advanced Sealing Devices, we make and design reliable oil seals for your demanding tasks. If the oil seal is not selected properly, then even a few percents of leakage can be inconvenient and incur expenses to a large number of users, as well as cause environmental pollution. Note that the oil seal is not only to seal lubricating oil, it can also be used to seal other fluids such as water, foodstuff and chemicals. We understand that the reliability and reputation of your system depends on the well functioning of these oil seals.
Standard oil seals operate in a splash environment with no pressure or little pressure as low as 0.3 &#; 0.5 bars. If you have a higher pressure requirement, contact us and we can provide you with a different type of oil seal design. If a standard type of oil seal is used in a high pressure situation, lip distortion and wear will occur. This will shorten the lifespan of the oil seal and create unnecessary downtime. If your housing tolerances are not controlled as closely as standard housings, we can make the outer casing of oil seals with special profile so that the oil seals can seat properly in your housing before the assembly press tool is removed.
If you application is such that the lubricating liquid is not continuously available, or the operating temperature, fluid compatibility, the speed and pressure are of a more demanding nature, then we can make oil seals using stainless steel outer casings with various pure and filled PTFE lips (type ASD SS-PTFE). This type of oil seal is now widely used by our customers in the automotive and transmissions industry. A stainless steel casing with a PTFE lip oil seal will support more highly rated machinery and allow longer oil change intervals. Our ASD SS-PTFE type is particularly suitable for dry running application, for example, an engine may run dry for some period during startup until oil splash is available especially after a long period of storage or transportation. There are certain design aspects that are required in your system before using our ASD SS-PTFE type oil seal; contact us and we will advise you on this aspect. The following are some examples of stainless steel oil seals we make for our customers.
Beside oil seals, we can also make sealing devices which seal on the radial face of your system, as opposed to the axial face for oil seals. With this type of seals, your shaft surface finish can be less critical and the seals can operate with minor runout and misalignment.
In making oil seals, we employ modern polymeric seal materials and we rely on our good understanding of the sealing mechanism that occur at the sealing interface. We will thus provide you with reliable oil seals and also to enhance protection of the environment. We offer the following types of oil seals:
Type
Code
Description
Applications
Speed (m/s)
Pressure (bar)
SAA
Metal casing and reinforced inner ring, sealing lip with garter spring
dust free application
30
0.5
SAB
Metal casing, sealing lip with garter spring
dust free application
30
0.5
SAC
Rubber casing and metal insert, sealing lip with garter spring
dust free application
30
0.5
TAA
Metal casing and reinforced inner ring, additional dust lip and sealing lip with garter spring
dusty application
30
0.5
TAB
Metal casing, additional dust lip and sealing lip with garter spring
dusty application
30
0.5
TAC
Rubber casing and metal insert, additional dust lip and sealing lip with garter spring
dusty application
30
0.5
KAA
Metal casing and reinforced inner ring, additional dust lip and rubber sealing lip
oil or dust seal, for dusty application
10
-
KAB
Metal casing, additional dust lip and rubber sealing lip
oil or dust seal, for dusty application
10
-
KAC
Rubber casing and metal insert, additional dust lip and sealing lip
oil or dust seal, for dusty application
10
-
VAA
Metal casing and reinforced inner ring, rubber sealing lip
oil or dust seal
10
-
VAB
Metal casing, and rubber sealing lip
oil or dust seal
For more information, please visit Dingtong.
10
-
VAC Rubber casing and metal insert, sealing lip oil or dust seal 10 - HATC-R Metal casing, sealing lip with garter spring and hydrodynamic rib, right rotation engines or transmissions 30 0.5 HATC-L Metal casing, sealing lip with garter spring and hydrodynamic rib, left rotation engines or transmissions 30 0.5 ACN Metal casing and reinforced inner ring, additional dust lip and sealing lip with garter spring; high pressure application 15 10 DAC Rubber casing, metal insert, and double sealing lips in opposite direction separating two types of oils 10 0.3 DAB Metal casing, and double sealing lips in opposite direction separating two types of oils 10 0.3 SACY Seal is fixed by clamping the flange, low friction reciprocating motion, for hydraulic control valves 10 6 SACJY With nylon backup ring for high pressure reciprocating motion with large shaft misalignment 10 6 TAC4 Rubber casing with metal insert reciprocating motion, designed to minimise lip deformation 1.5 0.3 TAB4 Metal casing reciprocating motion, designed to minimise lip deformation 1.5 0.3
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Type
Code
Description
Speed (m/s)
Pressure (bar)
RFS
Rubber fabric with spring sealing lip
15
0.5
RFSD
Rubber fabric with spring sealing lip and additional dust lip
12
0.5
RFSH
Heavy-duty steel mill roll neck bearing seal with steel band
15
5.0
RFSSP
Rubber fabric with spring sealing lip (split design)
12
0.5
RF
Rubber fabric with springless sealing lip
2
0.5
RFD
Rubber fabric with double springless sealing lip
12
0.5
RFWRR
Rubber fabric rod wiper for rotary and reciprocating applications
2
0.5
RF0S
Rubber fabric with outside spring sealing lip
5
0.5
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Type
Code
Description
Speed (m/s)
Pressure (bar)
RS6
Most common profile, with sizes up to 2 metres, for gearboxes, electric motors and drives
10
-
RS6A
Compact v-seals, used in confined spaces
10
-
RS6B
Heavy-duty v-seals, for rolling mills
10
-
RS6C
Heavy-duty v-seals, for rolling mills, papermaking and large machine
10
-
RS6D
Heavy-duty v-seals, unique profiles to accommodate radial and axial support, for metals and paper mills
10
-
RS7
Wide body and tapered heel to hold ring on shaft firmly, for agricultural and automotive applications
10
-
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Type
Code
Description
Speed (m/s)
Pressure (bar)
RS10
PTFE sealing ring with preloading elastomeric o-ring element - for internal rotation
2
300
RS11
PTFE sealing ring with preloading elastomeric o-ring element - for external rotation
2
300
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Type
Code
Description
Speed (m/s)
Pressure (bar)
TSM
Metal casing with machined PTFE sealing lip
30
20
TSF
Metal casing with formed PTFE sealing lip
25
15
TSFD
Metal casing with formed PTFE sealing lip and additional PTFE dust lip
30
10
TSF2
Metal casing with double formed PTFE sealing lip
25
20
TSF2D
Metal casing with double formed PTFE sealing lip and additional PTFE dust lip
25
20
TSMS
Metal casing with machined PTFE sealing lip and garter spring
10
10
TSMSD
Metal casing with machined PTFE sealing lip and garter spring and additional PTFE dust lip
10
10
TSM2S
Metal casing with double machined PTFE sealing lip and garter spring
10
10
TSM2SD
Metal casing with double machined PTFE sealing lip and garter spring and additional PTFE dust lip
20
10
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Type
Code
Description
Speed (m/s)
Pressure (bar)
TUcRT
Reduce friction; O-ring in OD, ID lip chamfered, canted-coil spring
5
210
TUvRT
Good sealing; O-ring in OD, ID lip chamfered, cantilever spring
5
210
TUcRR
Reduce friction; O-ring in OD of heel, ID chamfered, canted-coil spring
5
70
TUvRR
Good sealing; O-ring in OD of heel, ID chamfered, cantilever spring
5
70
TUcL
Reduce friction; OD flanged, ID chamfered, canted-coil spring
5
210
TUvL
Good sealing; OD flanged, ID chamfered, cantilever spring
5
210
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Type
Code
Description
Speed (m/s)
Pressure (bar)
TC1RT
Sealing Lip (formed) with O-ring in OD
10
4
TC1SRT
Spring Energised Sealing Lip (formed) with O-ring in OD
25
4
TC2RT
Sealing Lip (machined) with O-ring in OD
30
2
TC1DRT
Sealing Lip (machined) with Dust Lip and O-ring in OD
25
4
TC3RT
Double Sealing Lip (formed) with O-ring in OD
25
10
TC3DRT
Sealing Lip (formed) with Dust Lip and O-ring in OD
25
10
Also known as a Rotary Shaft Seal, Shaft Seal, Lip Seal, Elastomeric Lip Seal or any variation of these. It is a simple device for excluding dust, dirt, water or any other contaminant whilst retaining lubricant in rotary shaft equipment. Generally, it has been developed as a means of protecting the bearings of rotating shafts.
In this blog, we attempt to highlight what are Oil Seals and the various Rotary Shaft Seals including Mechanical Face Seals, Water Pump Seals, Gland Packings, and V-Seals that are readily available.
The basic principle of sealing is straightforward &#; the flexible lip is held against the rotating part (usually the shaft) whilst the casing (or O.D.) is pressed into the housing or bore and holds the seal in place. The sealing lip needs some form of lubrication to avoid overheating and is usually energized by means of a garter spring.
Many &#; too numerous to list, covering a vast range of designs, sizes, and materials suitable for a never-ending range of applications. Some designs conform to International Standards such as BS and DIN for metric sizes and seal types, but the majority have been manufactured to suit particular applications &#; hence the enormous selection available. This blog is intended to assist in this selection and will consider seal type, materials, and sizes.
The simplest way is to know either the preferred manufacturers part number, the overall sizes of shaft diameter, housing diameter and bore depth, or use our brochure to establish the M Barnwell Services ordering reference. Many of the old traditional names of seal manufacturers have either changed or disappeared in this age of &#;acquisitions&#;. If no longer available, we will advise you and offer a suitable alternative seal, from stock whenever possible. If your concern is getting the right seals for the job, you will need to know something about the application as well as the overall sizes. If you have any doubts &#; contact us, we will help in your seal selection.
Leather is probably the oldest of the lip materials still in common use, but the move towards mass production methods has seen a massive increase in the development of synthetic rubbers which lend themselves to accurate and repeatable injection and compression moulding. Nitrile (NBR) is still by far the most common elastomer for &#;normal&#; use, whilst Viton® (FKM/FPM) is rapidly replacing Polyacrylate (ACM) and Silicone (VMQ) for high-temperature applications. Viton® also has high resistance to abrasion and chemical attack making it a preferred elastomer. Recent developments in the use of PTFE for Rotary shaft seals has caused widespread interest particularly for high-speed shaft rotation or poor lubrication applications.
Once you have selected the most suitable seal available, considering the environment, temperature, shaft speed, pressure, lubrication availability, as well as the size, of course, the seal should be stored adequately and then fitted properly. Here are a few suggestions that could help:-
There is a British Standard laid down for the control of synthetic rubbers. BS () helps to determine shelf life &#; for instance, Nitrile (NBR) and Polyacrylic (ACM) are Group &#;B&#; rubbers and have a 7-year life, whilst Silicone (VMQ) and Fluoroelastomers (Viton®) are Group &#;C&#; rubbers and have a 10-year shelf life. PTFE and Leather do not come into this category but like the others should be kept in the original packing for as long as possible away from direct light, dust, and humidity. Ozone, which can also be produced by battery-driven forklift trucks has a very bad effect on synthetic rubbers. Finally, protect the sealing lip &#; DO NOT hang the seals on nails, wire etc.
If the seal is being fitted to original equipment you may have some influence over the shaft and housing bore finish, but if you are replacing a worn seal you still need to take into account the condition of these 2 essential parts. Check for sharp edges and burrs &#; particularly on the shaft and housing chamfers or you could ruin the seal before you start up. If the shaft is too worn consider using an M Barnwell Services Shaft Repair Kit.
If you want to learn more, please visit our website t type oil seal.