K21-P Piston Seal

Specifications

How to choose Piston Seals

Points to check when selecting, with the values for this product (K21-P).

1. 1. Match cylinder bore and groove dimensions

   The seal is designed around the combination of cylinder bore D, piston-side groove diameter d, and groove width L. If these three dimensions do not match, excess or insufficient squeeze (the amount by which the seal is compressed) causes leakage, premature wear, or improper installation. When replacing parts on existing equipment, measure the groove and check whether a matching dimensional series is available.

2. 2. Choose single-acting or double-acting by application

   Use single-acting types for cylinders pressurized on one side only, and double-acting types for double-acting cylinders pressurized in both directions. Single-acting types often have asymmetric cross-sections, and sealing fails if they are installed in the wrong orientation. Double-acting types generally have symmetric cross-sections and seal pressure in both directions with a single seal.

3. 3. Allow margin for maximum pressure

   This product: Maximum Pressure 400 bar

   The listed products have maximum pressures ranging from 25 to 1500 bar. Compare them using the maximum pressure including surge pressure (momentary pressure spikes). At high pressure, extrusion into the clearance gap is more likely, so backup-ring-integrated designs or high-pressure-rated profiles are good candidates.

4. 4. Select material by fluid and temperature

   Polyurethane-based materials offer excellent wear resistance and pressure resistance and are widely used in hydraulics. PTFE-based materials have low friction and high chemical and heat resistance, making them suitable for chemical and food applications. Rubber-based materials such as NBR are common materials for mineral oil applications. Select a material compatible with the working fluid and temperature range (listed products include examples from -60 to 260°C).

5. 5. Check sliding speed and friction characteristics

   This product: Maximum Sliding Speed 0.5 m/s

   The listed products have maximum sliding speeds of 0.3 to 15 m/s. High-speed operation and frequent reciprocating motion increase heat generation and wear. In low-speed positioning, stick-slip (vibration caused by sticking) becomes a concern, so profiles with PTFE-based slide rings, which have low breakaway resistance, are suitable.

6. 6. Consider integrating guide functions

   Profiles that incorporate guide ring functions allow a shorter piston length and reduce the number of components. However, when lateral loads are high, designs that combine a separate guide ring are common. Select the profile after reviewing the groove configuration and lateral load conditions.

This guide was written by AI based on the listed products' documents and specification items.

About Piston Seals and all products

Description

Symmetric-section lip seal with built-in O-ring. The acute sealing lip seals well against high-viscosity fluids and can also be used as a wiper seal.

FAQ

Q. What types of fluids can the K21-P Piston Seal be used with?

A. The acute-angle sealing lip provides good sealing even with high-viscosity fluids.

Q. What applications and conditions can the K21-P Piston Seal be used under?

A. It can be used for rods, pistons, and wipers. It can also be used as a wiper seal. The operating temperature range is -50 to +100 °C, the maximum sliding speed is 0.5 m/s, and the maximum pressure is 400 bar.

Q. What is the structure and type of the K21-P Piston Seal?

A. It is a symmetric-section lip seal with a built-in O-ring. It is a single-acting lip seal.

Written by AI based on the content of the source documents.

Source documents

• Catalog 切削加工シール製品ラインアップ 84 pages Open page 23
  Found on: https://azuma-eg.com/catalogue/