SPUR GEARS 9 CONTENTS SERIES 101 Acetal : Module 0.5 - 3 p. 103-109 Delrin : Module 0.5 - 3 p. 110-115 Helical Brass/Steel : Module 0.3 - 1 p. 116 Brass : Module 0.3 - 1 p. 117-120 Steel : Module 0.5 - 6 p. 121-149 Stainless Steel : Module 1 - 3 p. 150-151 Fax: +44 (0)1992 509890 101 SPUR GEARS Metric spur gears are available in a range of materials in module sizes from 0.5 to 6.0*. All of the gears in this section have an involute tooth form with a pressure angle of 20. The module sizes quoted in this catalogue are in accordance with DIN780. *Larger modules are available to order. For examples of tooth profiles and geometrical data, see Technical Information pages 192 - 194. Material Data for Plastic Gears Symbol / Units Delrin Acetal Quality Opaque Procelain Opaque Procelain 3 Density g / cm 1.425 1.41 2 Tensile Strength N / mm 70 65 s Elongation at failure R % 25-40 40 2 Modulus of Elasticity E n / mm 3300 3100 2 Hardness H N / mm 170 140 k 2 Creep strength after 1000 h static load 1000 N / mm 40 40 s, Sliding coefficient of friction* 0.34 0.32 Melting Temperature T C 175 165 s Heat resistance (ISO process A & B) F C A/B 124 / 70 100 / 70 iso Operating temperature limit (intermittent) T max i C 160 150 Operating temperature limit (continuous) T max c C 100 100 Coefficient of thermal conductivity W / Km 0.31 0.31 Specific Heat capacity c kJ / kg K 1.5 1.5 5 Linear extension coefficient 10 / grd 10 10 9 Dielectric Number 3.7 3.5 r Dielectric loss factor 0.0005 0.003 tan Current flow resistance .cm pD Dielectric strength kV / mm >50 >50 Ed Creep tracking resistance KA 3c KA 3c - Diluted Acid Diluted Alkaline Hydrocarbons (saturated oils/fats) Aromatics Ketones, Esters Chlorinated Hydrocarbons Hot water washing Resistant Conditionally Resistant Not resistant Humidity uptake NK 23/50 (sat.) CWN % 0.3 0.3 Water uptake (sat.) CWS % 0.5 0.5 Max lengthening by humidity in NK 23/50 1/ 1N % 0.15 0.15 Combustibility (ASTM-D635 or UL-55) b. b. Outdoor exposure UV Sensitive UV Sensitive Tel: +44 (0)1992 509888 102 Electrical Other Data Chemical Resistance Thermal Properties Mechanical Properties Properties