Pneumatic Seals and Hydraulic Seals: Types and Materials Discussed

Nov 25, 2024 Rubber Seals

Seals are super important in machinery and engineering equipment used across industrial processes to avoid air exchange, spillage, and more. Pneumatic and hydraulic seals are especially used to separate gases and liquids, respectively, within a chamber or cylinder and can be machined to be molded or formed as per requirements. Such custom hydraulic seals and pneumatic seals can be used for dynamic sealing in cylinder applications with rotary motion. Some of these applications include earth movers, excavators, farming equipment, and hydraulic cylinders. In this post, we'll discuss the various types and materials of pneumatic and hydraulic seals and why they're so important in different industrial applications. So, keep on reading!

Know More About Pneumatics Seals and Hydraulic Seals

Understanding Pneumatic Seals and Hydraulic Seals- Definition & Function

Pneumatic seals prevent air or gas leakage in pneumatic systems that operate using compressed air or gas. These seals maintain the efficiency and safety of pneumatic systems by ensuring that the compressed air remains within the system and does not escape. On the other side, hydraulic seals prevent fluid leakage in hydraulic systems, which utilize liquid (typically hydraulic fluid) to transmit power. These seals ensure the efficient operation and longevity of hydraulic machinery by ensuring the hydraulic fluid remains within the system and does not leak out.

Types of Hydraulic and Pneumatic Seals

Pneumatic and hydraulic seals come in several types. Here are some of them.

Piston seals:Piston seals can be used as both pneumatic and hydraulic seals. They are available as single-acting and double-acting seals and can be utilized with backup rings and guide rings.
Vee packs: These seals consist of multiple Vee rings and include male and female adaptors. These seals can be used with both double-acting and single-acting cylinders.
O-ringsO-ring seals help in controlling fluid or gas leakage in the system.
Backup rings: These seals reduce extrusion risk under pressure. These rings are known as anti-extrusion rings because they do not have a sealing function of their own.
Backup rings:These seals reduce extrusion risk under pressure. These rings are known as anti-extrusion rings because they do not have a sealing function of their own.
Rod seals:These seals prevent fluid leakage at the rod exit, which is usually used in pneumatic cylinders and actuators.
U-cup seals: These seals are used in low-pressure systems and come in various materials and sizes. U-cups help reduce friction even for less-rounded components.
T-seals: These seals are used in piston and rod styles to control spiraling and extrusion. Sometimes, T-seals are also used in place of O-rings.
Wipers: These seals are also known as scrapers that prevent contaminants like dirt, dust, and moisture from entering the pneumatic system along the rod. These types of seals are usually used in cylinders and actuators where the rod extends into the external environments.
Guide rings: These seals help in guiding piston rods and pistons in a cylinder.

Materials Used in Hydraulic and Pneumatic Seals

Types of Hydraulic and Pneumatic Seals

Here are some common materials used in hydraulic and pneumatic seals.

Nitrile Rubber (NBR): This material, also known as Buna-N, is a synthetic rubber that is widely used for hydraulic seals due to its excellent resistance to petroleum-based fluids, hydraulic oils, and greases.
Polytetrafluoroethylene (PTFE): This material, commonly known as Teflon, is a high-performance plastic material known for its exceptional chemical resistance and low friction properties.
Polyurethane (PU): It is a versatile material known for its outstanding mechanical properties, making it ideal for hydraulic seals in applications requiring high wear resistance and load-bearing capacity.
Fluorocarbon Rubber (FKM): They are commonly known as Viton and offer excellent chemical resistance and high-temperature stability, making them suitable for demanding hydraulic applications.
Hydrogenated Nitrile Butadiene Rubber (HNBR):This is a hydrogenated version of NBR that offers improved resistance to heat, ozone, and mechanical stress, making it suitable for demanding hydraulic applications.
Ethylene Propylene Diene Monomer (EPDM): This is a synthetic rubber known for its excellent resistance to weathering, ozone, and water-based fluids, making it suitable for specific hydraulic applications.

Choosing the right pneumatic and hydraulic seals is crucial for your systems' efficiency, reliability, and longevity. By knowing various types of seals, the materials used in their construction, and the factors to consider when selecting them, you can ensure your equipment operates at its best. Also, ensure to source these seals from reliable pneumatic and hydraulic seals manufacturers and suppliers such as SSP Seals. They offer custom hydraulic seals to meet the needs of your specific applications. Contact their team today at +1 908-852-3125 or via mail at gm@sspseals.com.