Piston seal Varitef KH

spiralstainless steelcarbon

Product description
Varitef KH is a single-acting sealing element consisting of a PTFE sealing lip combined with a stainless steel spiral spring as preload. It is an active sealing element: as system pressure rises, the contact force on the sealing edges increases. Designed to bridge larger gaps, Varitef KH offers a wide usable temperature range and can be sterilized for applications in valves, pumps and blenders in food and medical technology. The PTFE compound is available with a special filler or carbon to improve compressive strength. Other material options are available on request. Due to the Varitef geometry, assembly in closed groove designs is limited; an open groove is recommended for easier installation.

Fields of application

• static
• dynamic
• single acting
• double acting (indicated but not primary)
• linear
• rotating (inactive)
• oscillating

Main use
valves, pumps, dosing equipment, food and medical technology

Materials
PTFE; PTFE with filler (special filler or carbon); metal components; stainless steel spiral spring as preload element

Technical values
Materials: PTFE with filler, stainless steel spiral spring
Pressure: up to 35 MPa
Temperature: -150°C to +225°C (material dependent)
Speed: up to 20 m/s
Note: Maximum values for temperature, speed and pressure are not simultaneously applicable and depend on material and media.

Technical specifications

• Type: single-acting sealing element
• Seal material: PTFE (options with special filler or carbon)
• Preload element: stainless steel spiral spring
• Capable of bridging larger gaps
• Sterilisable — suitable for food and medical applications
• Suitable for slow rotational movements and linear applications
• Pressure rating: up to 35 MPa (material dependent)
• Temperature range: -150°C to +225°C (material dependent)
• Maximum speed: up to 20 m/s (dependent on material and media)
• Assembly: limitations for closed groove designs; open groove recommended