Piston Seals
Piston Seals
A piston seal, also known as a piston ring or piston packing, is a crucial component in hydraulic and pneumatic cylinders, designed to prevent fluid or gas from passing across the piston as it moves within the cylinder bore. This ensures efficient operation by maintaining pressure differentials on either side of the piston, enabling the cylinder to perform its intended mechanical work.
Key Functions
Leak Prevention
Piston seals prevent fluid or gas from leaking past the piston as it moves within the cylinder, ensuring efficient operation.
Pressure Retention
They maintain the pressure differential between the two sides of the piston, which is essential for the cylinder to generate force and perform mechanical work.
Friction Management
Piston seals reduce friction between the piston and the cylinder wall, allowing smooth movement and minimizing wear.
Contaminant Exclusion
They help keep contaminants out of the cylinder, which can otherwise cause damage and reduce the efficiency of the system.
Shock Absorption
In some designs, piston seals also provide a cushioning effect, absorbing shocks and vibrations within the system.
Key Characteristics
Material
Rubber (Nitrile, Viton): Good elasticity and resistance to various fluids.
Polyurethane (PU): High wear resistance and excellent mechanical properties.
PTFE (Polytetrafluoroethylene): Low friction, high temperature, and chemical resistance.
Other Advanced Elastomers: Depending on specific requirements, such as high temperatures or aggressive chemicals.
Design
Single-Acting Seals: Used in applications where pressure is applied on one side only.
Double-Acting Seals: Suitable for applications where pressure can be applied on both sides of the piston.
Compact Seals: Combine multiple sealing elements into one, offering high performance in a smaller space.
Durability
High resistance to wear, abrasion, and extrusion.
Ability to maintain sealing performance over a wide range of temperatures and pressures.
Longevity even in harsh operating conditions, such as exposure to aggressive chemicals or high-pressure environments.
Flexibility
Capable of accommodating misalignments and deformations in the cylinder.
Maintain effective sealing despite variations in pressure and temperature.
Low Friction
Designed to minimize friction between the piston and cylinder wall, reducing energy loss and wear.
Compatibility
Compatible with various types of hydraulic and pneumatic fluids, ensuring effective sealing without degradation.
When To Choose A Custom Seal
Custom-designed sealing solutions play a pivotal role in addressing the diverse and intricate sealing challenges across various industries. As an expert, you understand that off-the-shelf sealing products often fail to meet the unique demands posed by specific applications, operating conditions, and...
Products & Resources
R. E. Purvis & Associates, Inc. is a recognized Sealing Technology Center for Parker's EPS (Engineered Polymer Systems) Division. Parker's EPS Division is a premier manufacturer of hydraulic seals which offers many geometric sealing profiles along with a vast selection of material options.
