Knorr K-rings Pneumatics

What are Knorr K-rings?

Knorr K-rings, better known as seals for Pneumatic Cylinders, are seals developed by Knorr-Bremse AG. These seals are mainly used in pneumatic cylinders and valves, where they prevent air leakage. In applications where compressed air enables movement, a well-functioning seal is a crucial component. If a seal does not function properly, air loss occurs, which can lead to pressure loss, reduced performance, and increased energy consumption.

The Knorr KA and KI rings stand out from other pneumatic seals due to their unique design, low friction, and smooth operation, even without additional lubricants. This ensures that these seals require minimal maintenance to continue functioning properly, thereby extending the lifespan of cylinders and valves in a pneumatic system. Additionally, these pneumatic seals are made from nitrile rubber (NBR), making them resistant to varying pressure and temperature conditions.

Different types of Knorr K-rings

Knorr-type pneumatic seals are an essential component in many pneumatic cylinders and valves. In a pneumatic cylinder, a seal can be used both in the piston and on the rod. Since these seals differ, there are two types of Knorr K-rings: the Knorr KA - Piston Seal and the Knorr KI - Rod Seal.

Knorr KA - Piston Seals The Knorr KA K-ring is a double-acting seal specifically designed for piston applications in pneumatic cylinders. This type of seal ensures that air is effectively enclosed, allowing a cylinder to move in both directions without pressure loss. The KA K-ring is often used in short-stroke applications, such as compact cylinders and valves. This seal is made from nitrile rubber (NBR), a material that offers excellent resistance to oils and fuels, maximizing durability. The Knorr KA K-ring can effectively operate within a pressure range of up to 12 bar and a temperature range of -30°C to +105°C. Thanks to its low friction, the piston movement remains smooth and efficient, minimizing wear on both the seal and the cylinder.

Knorr KI - Rod Seals The Knorr KI K-ring is designed as a rod seal and plays a crucial role in preventing air and fluid leakage along the piston rod. This type of seal was developed by Knorr-Bremse, a leading manufacturer of braking systems and pneumatic components, and is widely used in industrial cylinders. The KI K-ring is designed with low friction, allowing the piston rod to move freely without unnecessary resistance. This minimizes energy loss and extends the cylinder’s lifespan. Additionally, this seal is resistant to long-term use under varying pressure conditions, making it a reliable choice for pneumatic applications where minimal friction and maximum efficiency are required.

Knorr Pneumatic Seals for Cylinder and Valve Types

Knorr K-rings are widely used in pneumatic systems to prevent leakage and optimize the efficiency of cylinders and valves. These seals are essential for a wide range of components that operate on compressed air.

Pneumatic Cylinders Within pneumatic cylinders, Knorr K-rings are used in clamping cylinders such as the SDJ (double-acting) and SEJ (single-acting), as well as in standard cylinders like the DUJ series, including variants with cushioning (DUDJ), high-temperature resistance (DUHJ), magnetic pistons (DUMJ), and reinforced piston rods (DUVJ).
Directional Valves Knorr K-rings also play an important role in directional valves. They are used in manual and mechanical valves such as the W_J-01 / W_J-03, WBJ, WHJ, WTJ, WRJ, and WRLJ, as well as in pneumatic and solenoid valves like WKJ, SKVG, SIVG, WMJ, SMVG, and SMIVG.
Other Components Additionally, Knorr K-rings are used in quick exhaust valves (SEJ series), shuttle valves (DRJ-1/1), and flow control valves such as the ED-1/6 (bi-directional) and EDR-1/6 (uni-directional). Thanks to their versatility and reliability, Knorr K-rings remain an indispensable component in pneumatic applications.