Spur Gears Pinion Gear 5 Mod Transmission Gear 10~46 Teeth 45# Steel Flat Gear

Select the tooth count based on your required gear ratio and available space. Divide the driven gear teeth by the driving pinion teeth to get the ratio. For example, pairing a 10-tooth pinion with a 30-tooth gear gives a 3:1 reduction. A larger tooth count also increases the pitch diameter, which can help distribute load over more teeth for heavier-duty drives.

Module is the ratio of pitch diameter to tooth count. A Mod 5 gear has a pitch diameter of 5 mm per tooth — so a 20-tooth Mod 5 gear has a 100 mm pitch diameter. These gears will mesh correctly with any other metric Mod 5 spur gear or rack that uses a standard 20° pressure angle. Always verify both the module and pressure angle match before pairing gears.

45# carbon steel offers a tensile strength typically in the range of 600–750 MPa, making it well-suited for moderate-to-heavy mechanical drives. Actual load capacity depends on tooth count, face width, rotational speed, and lubrication. For high-cycle or shock-load applications, consider adding a lubricant to the mesh contact zone to extend service life.

45# carbon steel is not inherently corrosion resistant. For indoor or dry environments, the bare steel surface is adequate with periodic light lubrication. For humid or outdoor environments, applying a rust-inhibiting grease or coating to the gear teeth and bore is recommended to prevent surface oxidation.

Yes. These pinion gears are commonly paired with a Mod 5 gear rack for linear CNC axis drives, motorized gates, and sliding mechanisms. Ensure the rack also uses Module 5 with a 20° pressure angle. The pinion is mounted on the motor shaft and rolls along the rack to convert rotary motion into linear displacement.

Bore diameter and keyway dimensions vary by tooth count and gear size. Please refer to the variant options or contact us to confirm the bore size for your selected tooth count before ordering, especially if you need to match a specific motor shaft diameter.

Use the formula: Pitch Diameter (mm) = Module × Tooth Count. For Mod 5 gears, simply multiply 5 by your chosen tooth count. For example, 5 × 25 = 125 mm pitch diameter. This makes it straightforward to calculate center distances and gear ratios for your drive layout.