Pneumatic seals or pneumatic systems are utilized across various sectors, especially where robotics and mechatronics are deployed, thus automating workflows or in cases where a hydraulic system would be impractical. And where pneumatics is involved, a high-quality seal is essential! A pneumatic seal must meet stringent requirements, as it, like its counterparts in hydraulics, operates within dynamic systems. This article offers an overview of pneumatics' current applications, types of pneumatic seals, the requirements for pneumatic seals, and the materials employed for them. Did you know that approximately 60 percent of seal issues arise due to the use of incorrect materials? By employing the latest designs and materials, we cater to the needs of every industrial field.

Where is pneumatics used?

Pneumatics is indispensable in a wide variety of industries. Pneumatic cylinders, pneumatic valves, vacuum systems or grippers work with air pressure. Pneumatic systems are needed in medical technology and material handling as well as in robotics, drive and transport. Pneumatic systems are installed, for example, in air brakes of trucks and buses.
Air-filled tyres, pneumatic mail and pneumatic tools such as nailing machines, impact wrenches or pneumatic grinders are also dependent on pneumatics. Pneumatics are also used in mechanical engineering, process engineering, the mineral oil industry, mining and food production.
What is absolutely relevant is that pneumatic systems run perfectly: the right sealing technology – without pneumatic seals, which ensure the proper functioning of the systems, pneumatic systems would not run in industry. Precisely for this reason, it is important to maintain these spare parts well and replace them early. Because: Leaking pneumatic seals significantly increase the risk of downtime and production losses.

Piston seals are located between the piston and the cylinder wall. Its job is to create a pressure barrier and prevent fluid passing the piston. This pressure is required for controlling the cylinder motion or maintaining the position of the piston when at rest. Clearances between piston and cylinder wall are extremely tight and the piston seal performs a vital role in maintaining the relationship between these reciprocating components. Thus, correct seal size and material is critical to the performance of the cylinder.

A rod seal is a ring of elastomer material located between the reciprocating cylinder rod and the cylinder wall. Its job is to keep pressurized fluid contained within the cylinder whilst the rod extends and retracts. It is therefore critical to the operation of the cylinder because it keeps the operating fluid from escaping and allows the system to build the operating pressure required to move the actuator. Rod seals are also designed to maintain a thin film of fluid as the cylinder rod extends and retracts, which is important to help lubricate the rod, wiper seal and inhibit rod corrosion.

Buffer seals are usually located in front of the rod seals and serve as an extra line of defence in the event of an extreme spike in internal pressure. Preventing that pressure from reaching the rod seal and potentially blowing it out. Buffer seals also have a general regulatory effect on system pressure, ensuring smoother operation, better rod seal performance, and longevity by ensuring more gradual pressure buildup. Buffer seals also reduce the number of system contaminants such as metal particles that reach the rod seal, where they can do damage.

You will find hydraulic cylinder wiper seals at the mouth of the cylinder barrel in front of the rod seal. This is the seal that is usually visible when you inspect a cylinder externally. As the name suggests, the role of the wiper seal is to clear contaminants from the rod as the cylinder extends and retracts. It moves ahead of the rod seal and prevents external contaminants from getting under the seal and causing leakage, or entering the system and causing premature wear. The wiper seal also serves to retain the internal fluid lubrication film on the rod as it retracts.