Graphitic Material

This Grade is made from High Purity Natural Graphite, GB-grades are Silvery-grey in Colour, with a smooth-oily feel (to the touch). It is also a very suitable grade for large DC Machines as well as small battery operated DC Motors. They can also be combined with some other grades, to form Layered Brushes to lubricate the metal it is running on at high speeds. The GB-grades will have the following characteristics:

  • Excellent Lubricating Properties,
  • Relatively low Shore Hardness, but can be easily reinforced with Resin Impregnation,
  • GB-grades have a Current Density of up to 12 A/cm² continuously,
  • It has a higher Peripheral Speed than the EG-grades, and
  • Medium to low Specific Resistance than that of EG-grades.
  • Suitable for Commutators with Mica Under Cut.

111: Relatively soft and smooth – similar applications to GB 40, but for machines with steel or stainless steel rings and very high peripheral speed.

GB40: Soft, smooth, slightly polishing grade – used mainly on steel rings with a maximum peripheral speed of 50m/s.

GB 50: Soft, smooth grade – used in standard 3-Phase motors to turbo-alternators, large and small DC machines with high current ratings and high peripheral speeds, with a good film index.