Over the past two centuries, air motors have seen use in everything from airplanes to air-powered hand tools. With a long history and constant improvements, modern air motors offer a safe, reliable, and flexible solution for multiple industries. But what is an air motor? How can it benefit your project or application? How do you choose the right air motor for your needs?
What is an air motor?
Air motors, also called pneumatic motors, use linear or rotary motion to translate compressed air into mechanical work. From their safety components to their ability to work faster and harder than other motor types, they offer significant benefits for a variety of industrial processes. Air motors are used in many different applications across various industries. You can find air motors in use throughout the food, chemical and pharmaceutical, agriculture, petrochemical, and even the nuclear industry.
The benefits of air motors
So, how exactly do air motors benefit such a wide variety of industrial processes?
Safety
Safety is always a top concern when working with motors and heavy machinery. Air motors offer a few key safety features that make them stand out compared to other types of motors. They run cold, rarely overheat, and do not release sparks. This virtually removes the risk of fire or explosion when working with air motors.
Here’s how: As air motors use more and more air flow (the longer you use them), the motor becomes cooler. However, this is not the case for electric motors. Electric motors become hotter during use and must be shut off after a certain amount of time to allow them to cool off.
Flexibility
Air motors offer a power-to-weight ratio that is 2-3x higher than electric motors. This makes air motors perfect for applications that require both flexibility and power. So, if you need to fit a motor in a tight space or require portability, air motors offer the perfect solution.
Additionally, they do not need a complex control system. All you need to control an air motor is control over the air supply flow or pressure. With this simple control, you can change the torque or rotation speed. They can also be used in harsh temperatures ranging from -30 to 150 °C.
Reliability
Air motors provide unmatched reliability. An air motor does not heat up or degrade even at high cycle rates. While facility operators need to monitor the heat of electric and battery tools to avoid damage, air motors can be used non-stop. This is ideal for any production facility.
The cooling effect of air motors comes from the way air expands during its function. This air expansion cools the motor during operation, allowing you to ramp up production without overworking the machinery.
Choosing the right air motor
Finding success with an air motor in your operation requires you to choose the right product for your needs. Because there is such a wide range of air motor products available today, choosing the right air motor for your operation can become difficult. Here’s a breakdown of six factors to consider when choosing an air motor to help you select the ideal motor for your needs:
1. Look for product safety features
Safety needs to be a top priority for any facility or project with motors. To enhance the safety of your facility or project, always look for air motors with a few key safety features.
It is highly recommended that you use an SAT box. In this context, SAT stands for ‘Safety Air Treatment’. An SAT box is a safety device that provides several safety features. One of these features is an automatic motor shut-off. The type of motor shut-off provided by an SAT box gets rid of any leftover pneumatic energy. In addition, it is crucial to regularly inspect the supply line and connections. When in contact with compressed air, a line not properly linked to the motor can detach. This can cause it to become uncontrollable and dangerous.
2. Check for the necessary pressure in the network
A pneumatic motor converts pneumatic power into mechanical power. It’s important to make sure you have enough power at the input to get the motor to operate at full capacity. Before purchasing a new air motor, you should confirm your compressor can sustain enough air pressure and air volume (CFM or l/s) to power the motor. Without enough pressure and volume, the motor can still operate but its performance declines.
3. Check the required output
Though it might seem obvious, always check that the air motor you select can provide enough output for your needs. The output will depend on several factors, such as:
- Maximum output (HP/kW)
- Free speed
- Maximum speed under load
- Minimum starting torque
- Maximum torque underload
- Stall torque
4. Maintain the airline infrastructure and the air quality
You can use an F/R (Filter, Regulator) for lube-free motors or an FRL (Filter, Regulator, and Lubricator) to ensure the air is filtered and lubricated for standard motors. The FRL unit should be no further than five meters from the motor or use a hose length less than 15 feet.
This is also useful for adapting the pressure to the desired level just ahead of the motor. This prevents load losses caused by supply lines that are too long. Additionally, it’s important to ensure that the volume of air (CFM or l/s) is meeting or exceeding the air consumption at the max output.
5. Assess the purity of the exhaust
When using a standard air motor that requires lubrication, the air emitted from the motor is a mixture of air and particles of the lubricant used. This can cause issues for some industries that require clean surroundings. Three different approaches can be taken to control the particles being released into a clean area:
- Use a lubrication-free motor that emits air just as pure as the air it was powered by
- Collect and remove the exhaust from the motor elsewhere, in an area free from the same constraints
- Filter the exhaust air to the desired level of cleanliness
In particular, the food, pharmaceutical/fine chemistry, and nuclear industries can benefit from lubrication-free air motors, such as those from Atlas Copco (many of which are also stainless steel!).
6. Check for weight and size restraints
While air motors offer a higher power-to-size ratio than electric motors, you still need to be conscious of any weight and size restraints of a facility or project. With this higher power-to-size ratio, air motors can fit a wide range of use cases. This includes everything from handheld tools to OEM machinery.
With relatively low weight, you can use the same air motor across multiple applications. This versatility can help enhance your facility's productivity compared to gas or electric-powered motors. It also boosts the ergonomics of machinery for operators.
To sum it up
The handheld and fixtured tool industries have heavily relied on air motors for the past two centuries. They offer the perfect solution for a wide range of use cases due to the safety, flexibility, durability, and reliability they provide.
Atlas Copco brings the experience you need to choose the perfect motor for your use case. With its wide range of products, you can rely on Atlas Copco for your unified air motor system, individual air motors, or handheld pneumatic tools.
Ready to make the switch? Contact Atlas Copco and schedule a demo today!