Helical Gears vs Spur Gears

Helical and spur gears are manufactured for mechanical drives, transmitting motion, power, and torque for a range of applications. Spur gears and helical gears represent two of the four primary groups of gear types; the other two are bevel gears and worm gears. Each gear type provides specific features and benefits, providing beneficial qualities for their respective applications.

Helical Gear & Spur Gear Teeth Orientation

The teeth alignments of helical and spur gears differ to accommodate various parallel shaft applications. With spur gears, when the teeth of mating gears contact, there is immediate impact or shock loading, causing vibration and reducing the gear’s service life. The helix-angled cut of a helix gear eliminates the problem of shock loading and premature gear wear by providing gradual tooth-to-tooth contact. Helix gears can carry higher loads.

What are the Basic Differences Between Helical Gears & Spur Gears?

Spur gears and helical gears share fundamental similarities, such as overall functionality. However, each gear’s unique design will dictate its intended application. Spur gears offer the simplest design, with straight teeth parallel to the gear axis. Conversely, helical gears have teeth cut in the form of a helix over the cylindrical blank. Both spur gears and helical gears are used to transmit power between a parallel driver and driven shafts.

What are the Complex Differences Between Helical Gears & Spur Gears?

Some of the more compelling differences between helical gears and spur gears are listed below.

Helical Gears	Spur Gears
Teeth are inclined at an angle (called helix angle) with the gear axis.	Teeth are parallel to the axis of the gear.
Imposes radial load and axial thrust load on bearings.	Imposes only radial load on bearings.
Utilizes both radial and axial load bearings.	Utilizes only radial bearings.
Used for both parallel and crossed shafts.	Used for parallel shafts only.
Engagement initiates with a point on the tooth face and gradually extends across the tooth.	During engagement, entire face of the tooth encounters the mating tooth.
Mating teeth load builds up gradually.	Mating teeth are subject to immediate impact loading.
Gradual teeth loading minimizes vibration.	Immediate load application increases vibration.
Noise-free operation, even at high speeds.	Produces noticeable noise due to sudden loading and vibration.
Pitch diameter increases as the helix angle increases.	Pitch diameter is calculated by Teeth/Pitch.
More complex manufacturing process requiring three-dimensional motion.	Cut easily using two-dimensional motion.
Transfers motion to shafts at angles of 0 to 90 degrees.	Transfers motion to parallel shafts.

Contact Ondrives.US for Premium Helical & Spur Gears Today

In the market for standard or custom gear products? Ondrives.US is your trusted source for precision helical and spur gears! Contact us to learn more about our helical and spur gear product options or request a quote for detailed pricing information today.