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Oil Seals

A reliable source for Oil Seals information and leading Oil Seals Companies & Manufacturers.

Oil seals, commonly referred to as shaft seals, are radial lip-type seals used largely to hold lubricants in machinery with revolving, reciprocating, or oscillating shafts. The most typical application is for spinning shafts. Read More…

Oil Seals Oil seals are rings made of various soft, non-metallic materials that are used to prevent leakage of liquids in hydraulic systems. A hydraulic system is a machine that uses pressurized hydraulic fluids to generate movement of equipment parts.
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Leading Manufacturers

Naples, FL  |  973-383-2487

We provide a variety of seals but hydraulic seals are our specialty! Just a few of the hydraulic seals that we are able to offer include hydraulic cylinder seals, hydraulic rod seals, and hydraulic piston seals as well as many others! For over twenty years we have been dedicated to providing our customers with exceptional customer service. To learn more about what we may be able to do for you, visit our website today! We are ISO 9001:2015 certified.

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Allied Metrics Seals & Fasteners, Inc. $$$

King of Prussia, PA  |  800-822-4063

Gallagher Fluid Seals offers an extensive line of hydraulic seals and pneumatic seals from many name-brand manufacturers. Our inventory includes o-ring seals, Teflon® seals, hydraulic packings, pneumatic packings, symmetrical seals, rod seals, piston seals, cup seals and many other products. With more than 50 years of industry experience, Gallagher's products and service offerings are second to none.

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Gallagher Fluid Seals, Inc. $$$

Grand Rapids, MI  |  616-538-4970

Kent Rubber Supply has been a trusted supplier of hydraulic seals since 1946. Focusing in exceeding customer service, we leverage the best equipment and the most knowledge staff to ensure we meet our customers unique needs. With our trusted experts, we determine the best rubber, foam, sponge or PVC material for your specific need. We continue serving customers both offshore and domestic.

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Kent Rubber Supply Co. $$$

Chandler, AZ  |  480-892-7325

Our list of inventory has grown since our founding over 20 years ago. We started small, but now offer an extensive product list of hydraulic seals, o rings, and other rubber products.

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Arizona Sealing Devices, Inc. $$$
placeholder image Allied Metrics Seals & Fasteners, Inc. Gallagher Fluid Seals, Inc. Kent Rubber Supply Co. Arizona Sealing Devices, Inc.

Oil Seal

The sealing part, the metal case, and the spring are the standard three parts of an oil seal. The sealing component aims to prevent fluid leakage between the shaft and housing. The metal case will offer stiffness and strength as the seal is retained in the bore or recessed groove. The garter spring maintains radial force on the shaft and constant pressure, flattening the sealing edge to a specified width. In addition, the garter spring maintains the sealing lip's radial force around the shaft surface. The environment the oil seal will operate must be considered when choosing any material.

An appropriate unit load must be kept at the seal-shaft interface for these seals to work as intended. These seals can withstand 15 psi of pressure, and their performance is influenced by factors such as shaft diameter, speed, operating temperature, service circumstances, etc. Any rotating and moving parts combination must include oil or shaft seals. Oil seals are widespread in hydraulic cylinders, gearboxes, etc. The seals are also known as "dynamic oil seals" since they are used in places where motion is an issue.

  • The function of the oil seals is to serve as a physical barrier that keeps the lubricant in the designated area.
  • Second, they stop the lubricating oil from leaking outside despite high pressure.
  • Third, it serves as a barrier to keep debris, contaminants, and other outside elements out of the system that contains the lubricating oil.

Constructional Aspects of an Oil Seal

  • The inner skeleton of the oil seal, which gives it structural support, is an inner metal ring.
  • Nitrile rubber and other materials, employed depending on the need, are used to make the outer skin.
  • The spring on the oil seal's lip tends to support the lip while preventing leakage of the lubricant outside and the admission of foreign pollutants.

Types of Oil Seals

Double Lip Oil Seals

Along with the standard sealing lip, this also has an auxiliary lip. This type is advised for usage in polluted areas because the additional dust lip shields the main sealing lip from dust and other fine solid pollutants. Again, a sufficient lubricant should be used between the two sealing lips to achieve a long lifespan.

Double Lip Seal

Advantages

  • reduced likelihood of fretting corrosion
  • good static sealing
  • compensating for varied thermal expansions
  • installation in split-housings
  • modern lip design offers reduced radial forces
  • effective protection against airside pollutants
  • Higher bore surface roughness is permitted.

Duplex Oil Seals

Occasionally, two distinct fluids will mix after leaking from one chamber to another. This kind is advantageous in this case. This duplex-type oil seal with metal inserts is suggested for use on assemblies where it's important to avoid mixing different fluids.

Oil Seals Without Spring

This kind of oil seal may tolerate only very little speed and friction. It is advised in locations that must be sealed off from thick fluid or grease. For challenging applications, this is not advised.

Materials Used on Oil Seals

Nitrile synthetic rubber is used to make oil seals, and steel stiffener rings are used. Other rubbers like Viton™, silicon, neoprene, or poly acrylic can be utilized for particular uses. For example, brass or stainless steel stiffener rings may be used when sealing extremely corrosive fluids. For corrosion resistance, most springs are composed of spring steel that meets IS 4454:Gr.ll standards, stainless steel, or bronze.

Types of Oil Seals

Type A Oil Seals

The interference fit between the flexible sealing element, often strengthened by spring pressure, and a shaft leads to the sealing of lip-type seals in most cases. Fluid retention is determined based on the precise amount of lip contact pressure. Most lip seals experience increased lip contact pressure on the shaft due to higher fluid pressure in the sealed area.

Advantages

  • reduced likelihood of fretting corrosion
  • good static sealing
  • compensating for varied thermal expansions
  • Installation in split housings is permitted, allowing for a higher bore surface roughness, and a modern lip design offers minimal radial forces.

Metal-Cased Oil Seals

Metal-cased oil seals are used when affixed to a housing bore of the same material. Due to the materials' ability to operate with equal levels of contraction and expansion, leakage is prevented. Generally speaking, rubber seals cost more than metal-cased seals.

Rubber-Cased Oil Seals

Rubber-cased oil seals are the most widely used oil seal implementation when a metal-cased oil seal has a probability of failing (for example, because of thermal expansion). In contrast to oil seals with metal casings, rubber-cased oil seals cannot rust. Additionally, oil seals with rubber cases are much more effective in sealing a housing with little damage than oil seals with metal cases. Fast-expanding rubber can provide a tight fit and more stable sealability at high temperatures and pressures.

The one that is used frequently is Type R. This kind has a carbon steel insert and a rubber outside diameter. Rubber has a great sealing ability even if the housing is not entirely within tolerance. The sealing lip with spring produces obstruction on the shaft for effective sealing. The outside diameter and inner metal reinforcement casing enable press-fitting in the housing with adequate interference on the rubber to ensure static sealing.

The sealing part is made out of nitrile rubber. Thanks to this and a high-quality galvanized steel garter spring, this oil seal has the longest lifespan conceivable. To prevent leaks brought on by a hydrodynamic pumping action, the sealing lip contact area on the sleeve or shaft must be devoid of any indications of machine life.

Type B Oil Seals

Type “B” oil seals resemble an "A" style seal. But, on the other hand, this has a metal case outside. This type is preferred with rugged housing, hot environments, and demanding jobs.

Advantages

  • Excellent fitting stability prevents the seal from popping out.
  • Low radial forces are provided by modern lip design.
  • outstanding radial rigidity, particularly for very large diameters
  • suitable for usage in conjunction with an axial seal
  • cost-effective for pricey elastomer materials

The outer layer of the skin often varies depending on how the oil seal is applied. Here are some materials used to make this oil seal's exterior skin.

  • The material that is frequently utilized for oil sealing is nitrile rubber.
  • Silicone is used in specialized applications with minimal stress.
  • Polyacrylate fluoroelastomer is also referred to as Viton™ in popular culture. When temperatures exceed 120° Celsius, high temperature-resistant materials such as this are utilized.
  • Polytetrafluoroethylene (PTFE)

Factors to Consider When Using Oil Seals

Several conditions must be met for the oil seals to function properly. These factors are:

  • The oil seal mounting shaft should be ground with a surface finish or roughness between 0.2 and 0.8 microns. The shaft should be hardened to at least 40 to 45 HRc. to avoid groove formation on the shaft due to the spring's pressure.
  • To avoid wear grooves, which typically tend to wear out the oil seal's lip more quickly, the area where the oil seal is positioned must be plunge ground.

Oil Seals Informational Video

 

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