Aligning and Resurfacing: Why Do It?


The first line of defense against poor dryer performance, reduced lifespan and excessive wear is aligning and resurfacing. Aligning and resurfacing services facilitate round surfaces, reduced vibrations, reduced wear on trunnions and tires, and extended life of trunnion bearings, trunnions wheels and the drum. Aligning and resurfacing your rotary drum dryer will also increase seal performance, which affects the dryer’s efficiency, capacity, and safety.  Keep your dryer running safely and smoothly with aligning and resurfacing.

The crucial first step toward the best dryer system is precision aligning, followed by resurfacing.  Thompson will align the dryer trunnion axles parallel to each other, using our proprietary alignment method.  We can raise or lower the drum to match the inlet and outlet as necessary.  Thompson Field Solutions technicians will use precision equipment to get your trunnion shafts within 1 thousandths ( < 0.001”) of parallel.

A precision alignment will decrease wear and tear on your system by reducing thrust. After alignment, the force from the drum weight will be riding straight down on the trunnion wheels, not pushing sideways from pressure on the bumper wheel or drive chain.  Thrust on bearings is one of the main causes for premature bearing failure.  Thrust can cause gouging and rough spots in the trunnion and tire surfaces, as well as putting excess stress on the drum drive system.  When not aligned, a drum has tendency to ride one bumper wheel or one trunnion flange, which can cause various problems depending on whether tire shims are used and what condition they are in.  Seals and seal surfaces can be at risk in a high thrust environment — either not covering the gap or getting jammed against the inlet or outlet.  Having a precision aligned system will significantly reduce your risk of unplanned shutdowns.

Dryer drum tires should be round and roll smoothly without vibrations or shock loading. Vibrations and shock loading are hard on the dryer drum and its components, especially the bearings, and will reduce their useful life. In addition, most dryer tires are not round, which causes premature seal failure. When combined with Thompson’s precision alignment, Thompson’s proprietary resurfacing technique will not only smooth, but also precisely round tires and trunnion wheels. This reduces vibration and shock loading, and diminishes wear and tear on the rolling surfaces and seal.Thompson is committed to providing the best service possible, including resurfacing while the dryer system is up and running at full capacity. Thompson believes the best results are achieved by first precision aligning and then resurfacing a system.  You can choose to include the sealing surfaces with this service as well.  

Using a special case of centerless grinding from the bottom of the tire allows Thompson to give you a better end product than conventional side resurfacing.  Thompson performs resurfacing while your dryer is in normal operation, using a proprietary technique to get your tracks and trunnion wheels smooth and round.  Resurfacing also removes micro-cracking that can begin to occur over time on dryer tracks and trunnion wheels as they roll against each other.  Smooth, round trunnions and tires will increase the life expectancy of the dryer drum.  

All rotary dryer systems need aligning and resurfacing every year or two. The best aligning and resurfacing service comes from Thompson Field Solutions. Don’t be happy with the status quo, be the best.