Carbon brush grades
GRADE DATA Many of the grades used today are derived through variations in raw materials, molding pressure, temperature, duration of the baking process and after-treatments. All brush grades fall into five categories and are represented by the tables below. CARBON GRAPHITE Grade Ohm (in) mOhm (m) Hardness PSI N/MM 2 VD CF Film # Amp/in 2 Amp/cm 2 H 0.0011000 27 55 3000 20.7 M M 1 40 6.2 H250 0.0008000 20 60 6700 46.2 M M 1 50 7.8 H357 0.0012000 30 50 2800 19.3 M M 1 55 8.5 H422 0.0100000 197 50 3600 27.9 H L 1 60 9.3 H990 0.0027000 67 70 4300 29.6 H H 1 40 6.2 NH12 0.0320000 800 45 3025 20.1 H L 1 55 8.5 NH16 0.0200000 500 25 2200 15.2 H VL 1 55 8.5 NH4 0.0016000 40 45 2500 17.2 M L 1 50 7.8 ELECTROGRAPHITE Grade Ohm (in) mOhm (m) Hardness PSI N/MM 2 VD CF Film # Amp/in 2 Amp/cm 2 H22 0.00075 18 45 3000 25.6 M L 2 70 10.9 H23 0.0015 37 70 4500 31.0 M L 1 70 10.9 H24 0.0016 40 55 4100 26.2 M L 2 80 12.4 H25 0.0012 30 65 5100 35.2 M L 2 80 12.4 H27 0.0017 43