How to Align and Grease Fan Couplings
Your direct-drive fan may use a coupling to connect the motor shaft to the fan shaft. The constant motion and friction within the coupling make coupling grease very important at start-up and throughout regular fan maintenance.
We carefully align and grease every fan coupling before shipment, but you should always double-check the grease levels (along with bearing grease levels) in your fan upon installation and regularly according to the manufacturer’s Installation and Operations Manual (IOM).
Proper Fan Coupling Grease Setup
To help you know what you’re looking for, we outlined the steps we take related to the coupling before we ship the fan to you.
Inside the coupling housing, there are two half couplings. One is for the fan shaft, and the other is for the motor shaft. Aligning the two sides is essential to preserve the life of the coupling and ensure proper operation of the fan.
We user lasers and a computer to measure alignment between the couplings on the fan and motor shafts. Our technicians then make any necessary adjustments to ensure the couplings are aligned within the correct millimeter tolerances. This process involves several simple steps:
- Assemble the couplings on each shaft and interlock them together with a grid.
- Attach laser levels to the fan shaft and motor shaft
- Take measurements in both vertical and horizontal positions.
- Adjust the fan and motor shafts as necessary and measure again.
- Repeat the measurement and adjustment steps until both couplings are aligned.
Once the coupling is aligned, it’s time to add the coupling grease.
Adding Coupling Grease
The coupling manufacturer provides packets containing the appropriate amount of long-term grease for installation and startup. Unlike general-purpose grease, long-term grease remains intact instead of separating with the ongoing rotation, which allows it to last longer. Here are the basic steps for adding coupling grease.
- Cut the corner of each packet provided and apply the grease into the grid and onto the coupling within the housing.
- While rotating the shaft, manually work in the grease until the grease packets are empty.
- Install the seals inside the split coupling housing.
- Assemble the coupling housing components and install them over both couplings.
- Set the proper torque on the coupling housing bolts.
Maintaining Coupling Grease
As with bearings, coupling grease is not one-and-done. Be sure to follow the IOM from the coupling manufacturer for recommended frequency of checking and replacing the grease on your coupling through the grease port right. As long as you do that, your coupling should last a long time.
Hear it from an Application Engineer
Chet White, Senior Application Engineer / Sales Manager, and Assembly Supervisor Clint Zwaard run through a detailed demo of coupling alignment and grease application in this 2½-minute video. To ask questions, get more details, or discuss your application, reach out and connect with one of our application engineers.
Here are many related posts that might be of interest as you think about your application.
- How Long Do Industrial Fans Last? Quality, Installation, and Industrial Fan & Blower Maintenance
- Fan Bearing Grease Management
- Check It Off. Avoid Downtime.
- Don’t Let Your Guard Down