A lot of old school pulley alignment is done by eye, but that simply isn’t good enough anymore. Many modern machines—such as forage choppers—transmit hundreds of horsepower through V-belts, and the quality of the pulley alignments on these machines can have a dramatic effect on power transfer and component life.
We have spent a lot of time analyzing V-belt drive failures in the field. Other than improper tensioning, pulley alignment is one of the main culprits for premature belt failure and pulley wear.
Nick Westerberg of Westerberg and Associates, a.k.a. The Pump DoctorTM, has shared with us a powerful technical review on pulley alignment. If you take away nothing else from his excellent paper, it is this: Use a laser alignment system for big machines. They cost plenty, but they will absolutely pay for themselves by saving fuel and extending the lives of pulleys and belts.
Many large machines use multi-grooved pulleys because they can transmit much more power than even the largest single-groove belts. However, because they have multiple grooves, misalignment problems will compound geometrically, so you simply can’t afford to cut corners.
There are a number of laser alignment systems on the market that should work well for you. However, we’ve purchased two SKF systems, and we’ve been very happy with them. They come with a complete range of replaceable seats, so you can use them on the full range of conventional belt groove shapes. You can pick up one at TEquipment for the low, low price of only $1,576.36. And no, we are not paid to sponsor them.
The Bottom Line: Maintenance pros and engineers need a tool to allow pulleys to be aligned with high precision without relying on a mechanic’s feelings and intuition. A laser alignment system will do the trick.