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  • How do I install piston seals?

How Do I Install Piston Seals?

Installation of Pneumatic and Hydraulic Piston Seals

Piston seals are popularly used for closing gaps or sealing off joints in hydraulic or pneumatic cylinders. They are designed to seal the cylinder bore and gland completely, thus preventing fluid from leaking out of the system. These seals have a decisive influence on the operation, performance, and longevity of your hydraulic or pneumatic cylinders.

Piston seals exhibit outstanding extrusion properties, exceptional resistance to wear, and excellent friction characteristics. Also, they are compatible with any process media, and offer unmatched performance in low and extreme temperatures.

Piston seals installed in closed grooves must be expanded or stretched into position. Seals with step cut slide rings such as are relatively easy to expand into position. Non-split profiles should not be expanded to a material deformation of more than 20% for TPU or 30% for rubbers. Otherwise, the permanent deformation would be too large. Heating the seal, e.g. in an oil bath, decreases the required expansion force, but cannot increase the maximum material deformation.

Piston seals with a TPU slide ring can usually be installed by hand or with simple tools. PTFE seals or those with thicker radial sections may require special assembly tools to save time or avoid seal damage

General Note on Installation

To achieve ultimate leakage control, it is essential to install the seals properly. The following are a few instructions that you must follow when installing the item in your hydraulic and pneumatic cylinders.

  • Use an installation sleeve in case the cylinder tube has not a lead in chamfer.
  • Deburr or chamfer sharp edges.
  • Clean the cylinder parts thoroughly. Chips, dirt and other foreign particles must be removed from the application area for effective sealing.
  • Inspect the parts that need to be sealed for any score or cut. Scratches on the surface could damage seals, leading to leaks.
  • Avoid installing the seal over sharp corners.
  • Use lubricants like oil or grease to install seals on the cylinder. However, ensure to use the lubricant that is compatible with the materials used in producing the seals.
  • Do not use any sharp edged installation tools, as they could damage the seal while installing.

The aforementioned are a few general tips that must be considered when installing pneumatic or hydraulic piston seals. Although these points seem basic, they will lead you towards successful seal installation. However, following only these points will not help. As an application user, you must read and understand the installation procedures of pneumatic and hydraulic piston seal provided by the respective manufacturer. When in doubt, speak to the manufacturer. S/he will guide you in installing the seal successfully in the application area.

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