Electrographite

Electrographite Material

Description
Electrographite has a high purity and very good frictional properties to protect both the Commutators and Slip Rings that it is running on, it is for this reason that the EG-grades are used in the widest range of applications. Depending on the composition ratios and the production process, these EG-grades will have the following properties:

  • good Electrical Conductivity,
  • relatively high Specific Resistance to suit many Commutation conditions,
  • high Peripheral Speeds,
  • reasonably low Co-efficient of Friction,
  • due to the extreme conditions that Traction Motors have on Carbon Brushes, Electrographite Carbon Co. produce EG-grades with high compression and flexural strengths to be able to withstand those Mechanical and Electrical Stresses, and
  • depending on the application of the Motor and certain external factors, the Current Density of the Carbon Brushes lies between 8 and 12A/cm² and peak loading of up to 300% for short periods of time, normally known as starting currents or occasional overloads.

Application
EG122 – EG102: A universal grade of carbon with very flexible applications. Used on slip ring as well as exciters, rotary converters, generators, alternators, regulators and welding machines. High and low tension machines with high current ratings. Generators on diesel electric locomotives, mining fan motors.

EG100 – EG110/2: A semi-hard and smooth grade – used on slip rings and commutators. Exciters – standard voltage and low tension machines up to 120V. Also for low voltage traction motors up to 60V DC.

EG8 – EG8/T: Semi-hard, flexible and shock resistant grade. Used in DC generators and motors of all voltage ratings, diesel electric locomotives generators and traction motors, battery operated vehicles.

EG127 – EG127/T: Semi-hard grade: Used in DC motors and generators also AC industrial machines, traction motors, battery operated vehicles, tramcars, crane mine winders, rolling mills.

EG129 – EG131/T: Semi-hard and flexible grades: for generators of both high and low ratings, AC commutator motors. Traction motors for AC & DC electric locomotives, rolling mills and mining extraction fan motors.

EG120 – EG120/T: Semi-hard, flexible and homogeneous texture grade: Used in high voltage DC motors, single phase traction motors as well as rolling plant motors.

EG32 – EG32/T: Semi-hard grade, used in AC &DC commutator machines of high and medium current ratings, very good commutation capabilities.

EG36 – EG36/T: Semi hard grade: for high current AC commutation rated motors.

EG36/R – EG40: For constant current rated DC machines of high speed, as well ad DC generators, motors, rotary converters and turbo alternator exciters.

TCE6 – TCE12: Very similar to the EG-grades, but with special treatment to suit the large thyristor control drivers. It is a long lasting, hard wearing grade with optimum commutation capabilities.