Double Lip Oil Seal Metal cased PTFE Double Lip Oil Seal is a seal that features a lip on the ID that fastens dynamically on a shaft and metal casing on its OD to press-fit into a bore. Besides, radial shaft seal with one or more PTFE sealing lips.
What are single lip and double lip seals?
Single lip and double lip Sealing rings The quality of a bearing arrangement is decisively influenced by the components – shaft, housing, seal – that are directly adjacent to the bearing. Seals play a decisive role in protecting bearings against contamination.
What is PTFE double lip seal?
Metal cased PTFE Double Lip Oil Seal is a seal that features a lip on the ID that fastens dynamically on a shaft and metal casing on its OD to press-fit into a bore. Besides, radial shaft seal with one or more PTFE sealing lips.
What is the function of the seal lip on a shaft?
The seal lip faces outwards. As in the case of rotating shafts, the sealing ring performs a dual function: ■ it retains the lubricant in the area to be sealed ■ it prevents contaminants from pe netrating the area to be sealed. The interference of the shaft and seal lip diameter determines the sealing action.
Why choose double seals?
These seals are increasingly used by companies to meet specific environmental goals or emissions requirements. A properly installed double seal also allows for near complete control over the seal operating environment and fluid film over the seal faces. This factor alone can greatly maximize seal life.
What is the difference between single lip and double lip oil seal?
Oil Seal Single Lip vs Double Lip 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.
What does lip seal mean?
Lip seals serve to protect lubricated moving parts and they do this by keeping the lubricant inside the bearing, and keeping contamination from dirt or other liquids out. The term lip seal is generally used to refer to what is correctly known as rotary shaft seals or oil seals or radial shaft seals.
How do you install a double lip seal?
2:015:31Radial Oil Seal Installation - YouTubeYouTubeStart of suggested clipEnd of suggested clipTo avoid angular misalignment the seal must also be installed perpendicular to the centerline of theMoreTo avoid angular misalignment the seal must also be installed perpendicular to the centerline of the bore to help a line and seat the seal.
What is a triple lip seal?
The triple lip shaft seals are specifically designed to effectively contain the grease in the system and prevent the entry of external pollution (water and mud splashes).
When would you use a dual lip seal?
Double seals provide a level of safety/zero emissions compliance not possible with single seals. This is essential when pumping or mixing a dangerous or toxic substance. These seals are increasingly used by companies to meet specific environmental goals or emissions requirements.
Where are double lip seals used?
(double lip): This design has NO spring and is generally used for sealing a non-pressure medium, such as grease and is used to protect against dirt as well as internal and external media.
How long do lip seals last?
(In actuality, advanced rotating labyrinth seals have an estimated operating life of 10 years.) The payback exceeds 3:1. This time, assume we use a lip seal and run it to failure. Allowing the lip seal to degrade might cause a bearing failure after perhaps two years of operation.
Why is lip seal important?
Lip-seal strength is important for articulating bilabials, capturing food during eating, maintaining fluid within the oral cavity before swallowing, and achieving swallowing pressure.
How much pressure can a lip seal hold?
Most oil, grease, and bearing seals with elastomeric seal lips are designed for zero pressure but will provide adequate service up to 3psi (0.2bar). Higher pressures will push the lip against the shaft and cause excessive friction and wear and rapid failure of the seal.
What is a multiple seal pump?
Multiple lip seals are commonly. used in centrifugal pumps and positive displacement pumps. There are many variations, but one version that has been particularly effective is a triple lip seal arrangement. The key feature is the third outboard lip seal element, which can be used for several functions.
Why is a lip seal used?
The radial lip seals are widely used in wet environments like ships, water pumps and tidal turbines. The lip seals keep the oil or grease lubricant inside the application and prevents the ingress of water and dirt.
Why is lip seal important?
Lip-seal strength is important for articulating bilabials, capturing food during eating, maintaining fluid within the oral cavity before swallowing, and achieving swallowing pressure.
How long do lip seals last?
(In actuality, advanced rotating labyrinth seals have an estimated operating life of 10 years.) The payback exceeds 3:1. This time, assume we use a lip seal and run it to failure. Allowing the lip seal to degrade might cause a bearing failure after perhaps two years of operation.
How do you fix lip seals?
Press your lips tightly together for 5 seconds. Relax and then repeat 5 times. Tightly press your lips around a tongue depressor, lip-closure spoon, or other approved device in the center of your lips while someone tries to remove it, for 5 seconds. Relax and then repeat 5 times.
What is the difference between a single lip and a double lip seal?
The difference between the single lip and double lip seals is that the double lip grease seal will have two rubber lips that are in contact with the spindle. The double lip grease seals are usually used in marine applications to give a better seal and protect the bearings from the water, which can cause damage to them.
How to determine what grease seals are needed for a spindle?
The best way to determine what grease seals are needed for your spindle is to get the part numbers from the inner and outer bearings from that spindle. If you have the bearing part numbers, then I can help you get the correct single lip or double lip grease seal that you will need. See the picture to the right that will show the cross section ...
What is double seal?
Double (or dual) mechanical seals are designed to ensure maximum sealing safety. These seals virtually eliminate leakage of the fluid or gas being handled in pumps or mixers.
What is double mechanical seal?
A double mechanical seal has two primary seals with a barrier or buffer fluid area in between. Each primary seal typically consists of a softer, narrower stationary face accompanied by a harder, wider rotating face. This arrangement enables the softer seal to wear while maintaining the integrity of the harder faced seal during service.
How to extend seal life?
To extend the life of any seal, you want to control the fluid film that comes into contact with the seal face. This establishes the ideal lubrication, temperature, and pressure. A dual seal allows you to control of all these factors. Double seals require fluid exchange between the inboard and outboard seal faces.
Why use fluid in a seal?
The fluid can also be used to remove process and frictional heat. It can combats issues with cavitation and dry running. The correct fluid set-up can also effectively direct the hydraulic load to the inboard or outboard seal to meet operational needs and to increase the life of the seal.
Why do we need double seals?
Pump and seal manufacturers recommend double seals for a variety of reasons: Prevent a hazardous product from reaching the atmosphere/polluting the environment. Avoid leakage of an expensive process fluid product. Maximize seal life by controlling the type of fluid film on the seal faces.
Why do companies use double seals?
These seals are increasingly used by companies to meet specific environmental goals or emissions requirements. A properly installed double seal also allows for near complete control over the seal operating environment and fluid film over the seal faces.
When to establish backup seal?
Establish a backup seal in the event of an inboard seal failure or planned equipment repair (or to identify seal failure during operation)
What is the purpose of lip seals?
The primary purpose of a lip seal is to exclude contaminants while retaining lubricants. By nature, lip seals function by maintaining friction. They can be used in a variety of applications from slow-moving equipment to high-speed rotation and in temperatures from below freezing to more than 500 degrees F.
How to install lip seal?
Lip Seal Installation Checklist 1 The elastomer is not damaged (no nicks, scratches, cuts, etc.) 2 The case is not damaged (no nicks, cuts, dents, etc.) 3 The garter spring is properly placed (if used) 4 Wipe the seal and shaft of any debris 5 The assembly lube is compatible with the lubricant in operation 6 The case is of the proper specification 7 The elastomer is of the proper specification 8 The lip seal is pointing in the correct direction 9 The shaft is free of defects (no nicks, scratches, grooves, etc.) 10 The bore is free of defects (no nicks, debris, roundness, etc.) 11 There is adequate ventilation of equipment when stored or in operation 12 Proper installation tools are used to avoid damaging seals 13 Equal pressure is applied during installation to ensure the seal is not cocked
Why does my pump seal leak oil?
Excessive pressure is another potential cause of lip seal failure. If you’ve ever walked past a pump or gearbox and noticed oil leaking out the seal, the sump has somehow overpressurized and leaked to the point of least resistance. This can be attributed to clogged breathers or non-vented sumps. Applications with higher pressures should employ a special seal design.
How to tell if a lip seal is failing?
While inspecting the shaft, you typically will see a contact or wear zone where the lip seal was riding. This will appear as a black scuffmark where the elastomer has transferred to the shaft.
How to prevent lip seal from sticking?
Always take time when installing lip seals, and lubricate the shaft and seal adequately to prevent tearing or sticking. Also, verify that the lip seal is the correct size. There must be an interference fit in the bore and on the shaft. Not having the proper size can result in the seal rotating on the shaft or becoming dislodged from the equipment.
What temperature do lip seals work at?
The most common lip seal material is nitrile (Buna-N). This material functions well at temperatures of minus 40 degrees F up to 275 degrees F. Nitrile lip seals cover most applications in industry from new equipment to replacement seals. They have excellent resistance to petroleum oils, water and hydraulic oils, but what really sets these seals apart is their low cost.
Why does my lip seal leak?
I’ve often seen a new lip seal start to leak as soon as it was put into service. This typically is due to improper installation. Other seals will leak initially but then stop leaking once the seal material has seated to the shaft.
What is an INA sealing ring made of?
INA sealing rings are made from elastomer materials. They are manufactured using pressing and injection moulding methods. Elastomers are wide-mesh, high-polymer materials with rubber-elastic characteristics. They exhibit viscoelastic behaviour, with the elastic influence predominant. Due to the viscoelasticity, elastomers gradually return to their original condition once stress is relieved. Elastomers are characterised principally by their hardness and compression or tension set.
What are the sealing rings on INA roller bearings?
FeaturesSealing rings of series G, GR and SD are matched to the small radial dimensions of INA drawn cup n eedle roller bearings with open ends and with closed end and of needle roller bearings without an inner ring. These contact seals protect the seal ed area against contamination, spray water and the excessive loss of grease. In comparison with spring-preloaded rotary shaft seals, they have significantly smaller cross-sectional dimensions, lower friction values and allow space-saving, economical sealing of shafts undergoing rotary and axial motion. The sealing rings are easy to fit, since they can simply be pressed into the housing bore. In rotary motion, sealing rings allow high circumferential speeds at the seal lip, depending on the surface quality of the shaft.
What are the materials used in sealing rings?
Sealing ring materialsThe sealing ring materials used and their characteristics are listed in the table Materials, ageing and media resistance, page 20. The elastomer materials are specified in a number of technical delivery conditions. Acrylonitrile butadiene rubber NBR Sealing rings of series G and GR are based on a high quality synthetic NBR elastomer material. The acrylonitrile (ACN) content essentially determines the characteristics of the NBR. As the ACN content increases: ■ the resistance to swelling in mineral oils, greases and fuels increases ■ cold flexibility and elasticity decreases ■ the compression set deteriorates. These characteristics show the opposite trend as the ACN content decreases. Sealing rings of series G and GR have a balanced composition and have particularly good resistance to wear and heat due to an active filler material. Fluoro elastomer FPM, HNBR Sealing rings of series G and GR made from fluoro elastomer (FPM and HNBR) are also available. Due to the FPM and HNBR quality, IN A sealing rings have particularly good resistance to heat and media (table Materials, ageing and media resistance, page 20). They are resistant to: ■ mineral oils and greases ■ fuels ■ poorly flammable fluids of type HFD ■ aliphatic and aromatic hydrocarbons ■ silicone oils and silicone greases. They are not resistant to: ■ polar solvents, brake fluids based on glycol and superheated water vapour. Thermoplastic polyurethane elastomer TPE-U Sealing rings of series SD have a lip area made from thermoplastic polyurethane elastomer. Due to its particular structure, thermoplastic polyurethane elastomer has rubber-elastic characteristics. It is highly wear-resistant and also resistant to environmental influences and many mineral oils. Polyurethane may change colour due to exposure to light. However, this does not influence the mechanical and chemical characteristics of the material.
What is the effect of coaxiality and runout on seals?
Caution! The coaxiality and runout influence the sealing function and wear at the seal edge. If the coaxiality between the shaft and housing bore is too large, Figure 3, the radial force will be distributed unevenly. This will lead to wear of the seal edge on one side and will reduce the sealing action. Runout deviations can, especially at high circumferential speeds, increase the seal gap and lead to leakage, Figure 4. Do not exceed the limit values for coaxiality and runout, Figure 5.
What is GR seal?
Sealing rings GRSealing rings GR have a single lip, are made from synthetic NBR elastomer (coloured green) and are suitable for shaft diameters from 4 mm upwards. They have external steel reinforcement for stiffening purposes and in order to increase seating of the sealing ring in the case of small sealing ring widths.
How long do sealing rings last?
Caution! If these conditions are not maintained, this may cause unfavourable changes in the physical characteristics of the sealing rings (e.g. hardening). Do not remove sealing rings from their original packaging until immediately before fitting. The maximum storage time from manufacture to fitting is: ■ 5 years for NBR ■ 10 years for FPM/HNBR.
How should sealing rings be stored?
Observe the storage room requirements in accordance with DIN 7716. Sealing rings should be stored at an air temperature of +20 °C 5 °C free from stress, i.e. without tension, compression or deformation. Do not allow the rings to come into contact with chemicals such as acids, solvents or fuels. Protect sealing rings from: ■ direct sunlight ■ UV light ■ ozone (e.g. produced by electrical equipment) ■ intense thermal radiation.
How does a lip seal work?
How lip seals work. Lip seals work with a small contact area on the liner, which in turn is placed around the shaft. The seal works due to a hydrodynamic lubricating film between the lip seal and its counter surface, this area is called the sealing gap and the film thickness in general is a few microns. The lubricating film is most stable between ...
What is the function of lip seals?
The function of lip seals. To accomplish the desired sealing solution, a lubrication film and high-pressure compensation are the main functions of rubber lip seals. The lubrication film forms a barrier between two media, such as water and oil. Another advantage is that the lip seal and liner do not make contact.
How does EAL affect seals?
EALs can chemically affect sealing rings by hydrolysis. Especially when emulsions are built up in the oil chambers of the sealing system or in the stern tube, these bio-oils interact with the water present and tend to break down. The lifetime of most NBR or FKM lip-type sealing systems will decrease due to this aggressive mixture. When using EAL, the use of Supreme® FKM-EAL lip seals is strongly recommended by Lagersmit.
How many lip seals are needed for rotating shafts?
All our sealing solutions for rotating equipment contain two up to five lip seals to ensure a reliable operation. The required number of double lip seals depends on the application and environment. Some to form a barrier against water ingress and another to prevent lubricant leakage into the environment.
Why would a lip seal be hot?
The temperature could increase due to friction/load on the contact zone, more shaft rotations per minute (RPM) or pressure difference over the lip seal. A higher temperature could lead to heat cracks and blistering of the lip seals. This could affect the seals reliability and will inevitably lead to leakage.
What metal is used for lip seals?
To make sure the lip seals stay in place, they are clamped in bronze or cast iron housing parts.
What is the difference between the pressure of a lip seal and the pressure of the lip seal?
The greater the pressure difference , the greater the friction and temperature increase will be .
