Varnish

Cryogenic varnish


Varnish features

The most common varnish for cryogenic installations is VGE-7031 varnish. It has good chemical resistance, bonds to various materials, and a fast tack time.

VGE-7031

  • Clear modified phenolic
  • Can be air-dried or baked
  • Use up to 470 K for 1 h to 2 h maximum
  • Varnish will not outgas after baking
  • Can be used in vacuum
    (1.33 × 10-6 Pa
    [9.98 × 10-9 Torr])
  • Superior electrical properties
  • Excellent chemical resistance
  • May be applied by dipping, roller coating, brushing, or spraying
  • Moderately good, low-stress adhesive
  • Enhances thermal contact

Note: May be thinned to the desired application viscosity with a 50:50 mix of denatured alcohol and toluene

VGE-7031 insulating varnish and adhesive possesses electrical and bonding properties, which, when combined with its chemical resistance and good saturating properties, make it an excellent material for cryogenic temperatures. As an adhesive, VGE-7031 bonds a variety of materials, has a fast tack time, and may be air-dried or baked. It is excellent for laminating many types of materials and may be applied to parts to be bonded and either baked shortly after applying or allowed to air dry and baked after the parts are stored and assembled hours, days, or even weeks later. It is also an electrically insulating adhesive at cryogenic temperatures and is often used as a calorimeter cement. VGE-7031 is compatible when dry with a wide variety of materials, including cotton, Dacron® polyester fiber, nylon glass tapes, laminates, Mylar® polyester film, mica products, polyester products, vinyl products, wire enamels, paints, rayon, plastics, and metals. When soaked into cigarette paper, it makes a good, high thermal conductivity, low electrical conductivity heat sinking layer.