How To Select The Right Spur Gear For Your Application

## Key Parameters for Spur Gear Selection ### 1. Module (m) The module defines the tooth size. Standard modules range from 0.5 to 50. Larger modules = larger teeth = higher load capacity but more noise. ### 2. Pressure Angle Standard pressure angles are 20° (most common) and 14.5° (older standard). 20° provides better tooth strength and is recommended for most applications. ### 3. Number of Teeth The minimum number of teeth to avoid undercutting is 17 for 20° pressure angle. More teeth = smoother operation but larger diameter. ### 4. Face Width Wider face width increases load capacity. Typical range: 8-16 times the module. ### 5. Material Selection | Material | Hardness | Application | |----------|----------|-------------| | S45C (Carbon Steel) | HB 200-270 | General industrial use | | SCM440 (Alloy Steel) | HB 230-280 | Higher strength applications | | SCM415 (Case Hardening) | HRC 58-62 | High wear resistance | | SUS304 (Stainless) | HB 187 | Food/chemical environments | ## Selection Checklist 1. Determine required torque and speed 2. Calculate gear module based on load 3. Select appropriate material for operating environment 4. Verify center distance constraints 5. Check for interference and undercutting 6. Consider noise and lubrication requirements Contact GRANGIN for custom gear manufacturing — we produce spur gears from module 0.5 to 50 with full material options.