5 Types of Gears Used in Industrial Wind Turbine Gearboxes

Gears are an essential part of so many industries, from the gears that are used in your car to the gears used in a wind turbine. Without these gears, some of the most important machines in the world wouldn’t work right. More importantly, these gears have to be manufactured to precise specs so they can do their job right, which makes them an even more critical part of machines.

In the wind power generation industry, there are a handful of different types of gears used. It’s important to understand the different types of gears and the pros and cons that come with each option, so you can choose the best type of gearbox for your needs. If you want to know more about the types of gearboxes that are commonly used in wind turbines, here’s what you need to know about the five most common options.

Planetary Gearbox

Planetary gearboxes get their name from the fact that their design is similar to the layout of the solar system. The “sun gear” is the largest gear in the gearbox and is situated right in the middle. The annular gear, also known as the annulus ring, acts as the outer ring for all the other gears, featuring internal teeth that allow the gears to move inside the ring. As the planetary gears on the outside of the box turn, they rotate around the sun gears thanks to the inner teeth on the annulus ring.

Pros

The main upside to planetary gearboxes is the fact that they’re incredibly efficient. Because of the way these gearboxes are designed, they offer better stability than other wind turbine gears and are resistant to shock. Plus, a high torque-to-weight ratio means planetary gearboxes provide excellent power.

Cons

Because of the way planetary gearboxes are designed, they can be noisy, and they tend to wear down fairly quickly. Regular maintenance and a good wind turbine oil system are a must when you’re using planetary gears.

Spur Gearbox

Spur gears are one of the more basic types of gears used in wind turbines, featuring straight teeth and parallel shafts for a simple design. Spur gearboxes often have gears of different sizes and gear ratios to make sure speed and torque requirements are met. These gears are most often made of steel or brass, both of which are common materials for gears. However, spur gears may also be made of polycarbonate and nylon.

Pros

Spur gears offer excellent speed control combined with high torque, which makes them a great solution for wind turbines that require speed regulation. With spur gears, you have more control over speed a torque.

Cons

The downside to spur gearboxes is pretty much the same as a planetary gearbox. Because spur gearboxes are generally made of steel, they can be noisy and wear down quickly.

Bevel Gearbox

While they’re not quite as common as planetary and spur gearboxes, bevel gearboxes are also used in wind turbines. These gears fit on top of each other with either straight or spiral teeth that matchup between the two gears. Because of the way they’re designed, bevel gearboxes are most commonly used in right angle applications. Bevel gearboxes can be made of several different materials, including cast iron, aluminum, and other metals.

Pros

The biggest benefit to bevel gearboxes is the fact that they can be used in spots where a right angle is needed.

Cons

If the teeth on a bevel gearbox aren’t cut just right, vibrations and noise are a common issue that gets worse over time.

Helical Gearbox

Helical gears are sort of a special type of gear, but they’re still fairly common in wind turbines. The teeth on helical gears are cut at an angle that allows for gradual, smooth contact, which makes these gearboxes one of the quieter options. These gearboxes are common in wind power plants that require a lot of power with high efficiency. Helical gears are generally made from cast iron, aluminum, or iron.

Pros

Due to the angle the teeth are cut at, helical gearboxes offer quiet operation that’s great for any application.

Cons

While the teeth on the gears won’t wear too quickly, hard axle load is a concern.

Worm Gearbox

Worm gearboxes are one of the most versatile and powerful types of gears, which is why they’re commonly used in so many industries. In wind turbines, worm gears are used for operations that require high speeds and large loads. These gears are quiet, powerful, resistant to wear and can even be configured for right angle applications, making them one of the most popular choices for wind turbines.