We offer a wide range of hydraulic seals suitable for different cylinder types and industries. Whether you need an individual seal or a kit for specific equipment we've got you covered.
The majority of our products are available with same day dispatch (before 2pm) and next day delivery (UK) with global shipping options also available.
Hydraulic Seal Types
There are many types of hydraulic seals out there and they come in a variety of shapes and sizes. Moreover they are specially developed to accommodate different variables such as cylinder speeds, temperatures, pressures and applications. They are designed to be placed in a cylinder or piston groove to form a seal that will prevent leakage in the hydraulic system, they are a critical component to keep machinery working correctly and operating safely.
The main types of hydraulic seals can be split into four primary groups:
Piston seals are dynamic hydraulic seals that are used to prevent the passing of any fluid beyond the piston as the system pressure forces the piston down the cylinder.
Single-acting piston seals only have to block the pressure from one side of piston, retaining the pressure which powers the piston to move along the cylinder.
Double-acting pistons require pressure from both sides to force the piston along the bore, meaning that in order to properly seal them you must use a double-acting seal that can seal the dynamic pressure from both sides. Sometimes however you can use two single acting seals in a 'back to back' arrangement in order to create a double acting seal system.
Rod seals are vital to maintaining an efficient hydraulic system, as they are responsible for both preventing fluid leakage from within a hydraulic cylinder and protecting it against dirt and other exterior contaminates.
Static seals that installed directly into the housing or glands of a system, rod seals are designed to provide dynamic sealing pressure while the piston rod is in dynamic motion.
Types of Rod Seals:
RFD Rod Seals: Also known as Single Acting Split Housing, these are heavy duty seals that also include an anti-extrusion ring for added protection. Made from rubberized fabric, the seal is simply added to the housing of a sealing area where it reduces friction and wear, keeping applications sealed and secure from harmful fluid leakages.
RTA Rod Seals: These Single Acting seals are used in hydraulic cylinders that have small groove dimensions. Fitted into the small housing, the RTA seals are combined with an NBR O-ring and PTFE inner to maximize sealing resistance against even the highest pressure.
RUB Rod Seals: Made for sealing piston rods, these Single Acting seals include an additional O-ring profile that lubricates and resists abrasions. RUB seals made from Polyurethane are most effective, including a 300 BAR resistance which is suitable for high-pressure systems.
Also known as scraper seals, they are often used together with other sealing components to let a ram rod pass through the inner bore of a seal, while preventing leakage.
Wiper seals are extremely important in ensuring that outside contaminants are kept out of hydraulic operating systems. By keeping everything from dirt to moisture outside of the system, scraper seals prevent any damage to rods, cylinder walls, seals and other important elements of the system.
When the wiper seals are not secured or fail, it can cause component failure in a fluid power system that leaves other pieces of the operation open to serious damage.
Most wiper seals are made from polyurethane and include a secondary lip that is used to catch any oil that has seeped past the main seal. The lip can also scrape any contaminants from the rod surface, giving them the title of “double-edged wiper seals”.
Types of Wiper Seals:
WRB Wiper Seals: These Medium Duty scraper seals have a special lip that help prevent moisture and dirt from accumulating on the rod. Made from an NBR compound, the seals are inserted directly into a grooved housing to provide a full seal in the system.
WRC Wiper Seals: Also including a lip, WRC seals do not extend past the cylinder cover. They are used in Medium Duty applications and can be installed into a simple groove design.
WCA Wiper Seals: Featuring a corrosion-resistant metal ring that encompasses the NBR seal, these Heavy Duty seals follow the side movement of the rod to keep it free from heavily deposited dirt.
WDA Wiper Seals: These double-function seals use the lip to prevent contaminants from building up, yet also have an additional element that prevents scoring on a seal. Used in Heavy Duty systems, WDA scraper seals can extend the service life of the seal by keeping them free from dirt, moisture and damage.
Guide Rings (Bearing or Wear rings)
Guide rings are designed to prevent two dynamic surfaces within a hydraulic system from rubbing together. Our Guide rings are available various materials such as Polyacetal, Fabric reinforced Phenolic Resin, Fabric Reinforced Polyester Resin, PTFE and Glass-Fibre reinforced Polyacetal.
Hydraulic Seal Materials
In order to maximise longevity and functionality in specific applications, hydraulic seals are made from a wide range of materials, each with their own unique properties. Based on criteria such as operating temperature, chemical interactions, pressure and fluid types, we select the materials that can handle each environment best.
The most common materials for hydraulic seals are:
- Polytetrafluoroethylene (PTFE)
- Polyurethane (PU)
- Nitrile (NBR)
- Viton (FKM).
To view our rubber and plastic chemical compatibility guide please follow this link.
If you need help selecting the right hydraulic seal for your system please don't hesitate to get in touch.