Boost your hammermill’s performance with a preshredder

When it comes to shredding, the downstream usually takes the spotlight. Focusing on maximizing scrap value through better nonferrous recovery is where people’s attention goes. But what if we told you the real secret to unlocking your operation’s full potential lies in what happens before material reaches the shredder?

Whether your goal is to reduce risks, boost throughput or cut down on wear and tear in the mill, preshredding is the key to unlocking your plant’s true capabilities.

At ZB Group, we’ve spent decades engineering solutions that go beyond brute force. Our line of preshredders is designed not just to feed your hammermill, but to transform your operation’s safety, efficiency and profitability.

Risk reduction

Combustible events continue to be one of the most serious hazards in shredding operations.

“When you process end-of-life vehicles, bales or unsorted light scrap, you increase your risk of an explosion and/or fire,” says ZB Group CEO Lander Arrieta. This risk isn’t just dangerous but costly, leading to downtime, damaged equipment and even regulatory penalties or complaints. Minimizing combustible events through preshredding is a smart, proactive way to operate.

Another significant safety improvement is the reduced risk from unshreddables—items like large solid steel components or other elements exceeding the mill’s recommended specs. “These items pose serious hazards, often causing severe damage and unplanned downtime in the hammermill,” Lander says. Preshredding minimizes that risk by removing a large portion of the unshreddables before they ever reach the mill.

That said, preshredding is no substitute for proper visual inspections and good material segregation practices. It’s an additional layer of protection, not a replacement for vigilance.

Higher throughput, greater consistency

Whether your system is already at capacity and you need to boost your volume, or you want to reduce capital investment in a new operation, preshredding will get you there.

A consistent feed allows smaller hammermills to perform comparably to larger, higher-power units—helping operators cut both capital and operating costs.

“On average, our customers see a more than 40 percent increase in hammermill throughput after integrating a preshredder,” Lander says. “Between the production increase and the reduction in wear costs, you can imagine how quickly you would recover your investment.”

The improved productivity makes preshredders an excellent solution for existing operations seeking to expand capacity without major modifications or the need for a new hammermill.

Low cost, longer equipment life

A uniform, controlled infeed means less strain on the hammermill, allowing it to run more smoothly. That translates to reduced wear on critical components such as hammers, wear plates and grates. This benefit applies to both diesel and electric mills, as consistent feeding helps prevent large swings in power demand, reducing both mechanical stress and energy consumption.

Despite their heavy workload, ZB preshredders are straightforward to maintain. “Most customers report only needing around five hours of hard facing per 1,000 GT processed,” says Victor Muñoz, After Sales Director at ZB North America. “Beyond that, it’s standard preventive maintenance—seals, filters and so forth.”

And while preshredders require far fewer consumables than hammermills, our service team in Atlanta is fully stocked and ready to assist whenever needed, ensuring minimal downtime. “American customers expect fast response and local expertise,” Victor adds. “That’s why we invested in a U.S.-based team and spare parts inventory. We take our responsibility seriously—we’re not just selling machines; we’re standing behind them.”

Built for your operation

No two yards are the same, which is why ZB Group offers two core preshredder models—PSZB 8360 and PSZB 10260—each available with multiple power options and customized shaft configurations to suit your exact requirements. Whether you’re processing cars, bales or mixed light scrap, we tailor each machine to your material and operational goals.

“Our units process anywhere from 30 to more than 120 GT/hr,” Lander says. “It all depends on the material type, shaft configuration and power setup. We have a solution no matter what your needs are.”

Why choose a ZB preshredder

While many preshredders may look similar from the outside, the difference lies in the engineering inside. ZB’s designs are the result of extensive research and development, incorporating tooth geometries and shaft configurations optimized for specific scrap streams, along with ZBrain, our proprietary automation platform.

“ZBrain isn’t just an accessory—it’s where the magic happens,” Lander says. “It continuously monitors hydraulic pressure, torque and available power, making real-time adjustments for maximum efficiency.”

In most installations, the crane operator feeding the preshredder also monitors its performance, simplifying staffing and boosting overall productivity.

Smarter upstream, stronger downstream

A preshredder isn’t just nice to have—it’s a strategic investment that unlocks the true potential of your hammermill. Fewer combustible events, extended hammermill life and dramatically improved throughput all add up to a smarter, safer and more profitable operation.

If you want to scale output, reduce operating costs or run a tighter and more controlled process, start by looking upstream. And when you do, ZB Group will be ready, with decades of engineering expertise, premium components and the full support of our U.S.-based team at ZB North America.

Call us today to learn more about how our shredding and preshredding solutions can take your operation to the next level—safely, efficiently and profitably.