Vermeer drum
Image courtesy Vermeer

Vermeer duplex drum design eases tree grinder maintenance

Engineers at Vermeer have created a drum that is different from anything previously available on the market with its Series III duplex drum.

November 1, 2022

A good drum makes all the difference when it comes to the performance and reliability of grinders in the marketplace.

“The drum is the heart of any grinder, and it has to last,” says Jeff Bradley, Vermeer Recycling and Forestry product manager.

The patented Series III duplex drum incorporates new technologies that make tree grinder maintenance convenient to help extend the wear life of your equipment.

Early drum design maintenance

Many of the early machine designs in the industry didn’t utilize a true rotor; it was more of a pin-and-plate design. Pin removal for hammer changes required high maintenance time with this design. If a business needed to replace a hammer in the middle of the rotor, a long pin had to be pulled through a series of discs and maybe two or three hammers. This increased the potential of creating out-of-balance issues while performing this task.

To avoid this, some manufacturers moved to a drum design. Hammers often were welded to the surface of the drum, however, the difficulty with welding hard materials made replacement and repairs more difficult and time-consuming.

Vermeer streamlines grinder maintenance with new design

Vermeer engineers constantly refine and improve products based on customer feedback. They addressed this drum design challenge and created a drum different from anything previously available - the Series III duplex drum. Now a featured component of Vermeer horizontal grinders and tub grinders, the Series III duplex drum is designed with reversible hammers and cutter tips. These innovations minimize maintenance time and ease replacement by eliminating the need to weld on hammers.

“To be hard you must have a lot of carbon, and when you have a lot of carbon you cannot weld it easily,” says Keith Roozeboom, engineer for the Recycling and Forestry Project. “We wanted to have something very robust, but not so difficult to replace, change or fix. What it comes down to is the through hammer design, which is different from anything that has previously been in the industry.”

The Series III duplex drum also features an improved hammer retention design over its predecessor that holds the hammers secure. A rounded hole in the drum to hold the hammer minimizes stress points in the drum versus the previous rectangular hole, preventing movement that could lead to wear.

Rebalance efficiency

Balance is critical on grinder drums. Consider that the drum on a Vermeer grinder can weigh 3,500 to 10,000 pounds, and when it’s spinning, it requires precise balance. As the drums wear, they need rebalancing. Being able to bolt weight onto the rotor end plate versus having to weld on pieces of metal eases the task.

Learn more about the Vermeer duplex drum

To hear more about the history of the duplex drum, watch this short documentary featuring Bradley and Roozeboom. They explain innovations made to the duplex drum with each series and share details about how the Vermeer duplex drum has transformed tree grinder maintenance for customers.

If you are ready to see how Vermeer grinders can make a difference for an operation, contact a local dealer to learn more or click here.