POWERcork 20

POWERcork 20

Gasket material POWERcork 20 is a mixture of cork and NBR elastomer. Suitable for very deformed flanges and most transformer oils. Complies with all current requirements for hazardous substances.

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Gasket material POWER®cork 20 is a mixture of cork and NBR elastomer.
  • Suitable for most transformer oils at observed operating temperatures.
  • Suitable for mineral oil, natural ester oil and silicone oil. Acceptable for use with SF6 gas.
  • Suitable for very deformed flanges.
POWER®Cork 20 is suitable for mineral and silicone oils according to:
  • ASTM D3455 -Test methods for compatibility of construction material with electrical insulating oil of petroleum origin.
  • ASTM D5282 - Test methods for compatibility of construction material with silicone fluid used for electrical insulation.
POWER®cork 20 complies with all current requirements for hazardous substances:
  • Does not contain asbestos
  • Does not contain heavy metals - Pb, Cd, Hg or Cr (VI)
  • Does not contain polycyclic aromatic hydrocarbons (PAH)
Quantity Method Value
Minimum operating temperature: - -40 °C
Maximum operating temperature: - +125 °C
Specific pressure range: - 2,5 - 15 MPa
Compressive strength: - >70 MPa
Density: ASTM D297 850 kg/m3
Hardness: ASTM D2240 65 Shore A
Tensile strength: ASTM D412, Die C 2,0 MPa
Elongation: ASTM D412, Die C 90 %
In order to improve the quality of our input control of materials for gasket production, we have purchased a tensile testing machine.

Now we are able to:
  • Check the mechanical properties of purchased materials
  • Verify the values stated on the supplier's materials sheets
  • Check the dimensions, hardness and quality of the material surface
  • Guarantee the customer's required parameters
Flat rubber-cork gaskets guarantee a sufficient contact area, thus reducing the risk of the gasket slipping out of the sealed surface area. They also provide excellent compressibility and can be used to seal out-of-flatness surfaces (unevenness, paint residue and deformations caused by welding, etc.)

Most of the flanges show load-caused deflection. The adaptability of the gasket is crucial under such conditions, and POWERcork materials provide tightness without leaks in these cases.

POWERcork has been subjected to very demanding aging tests (over 1500 hours at 167 °C, under pressure and in full contact with oil) to simulate a lifetime of more than 30 years.

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