Bakers are running their freezers harder and longer to maximize throughput and keep up with growth. It’s not unusual for continuous production runs to last 10 to 12 days — and in some cases longer — between routine cleaning and regular checkups due to enhanced sanitary design and advances in technology.

In recent years, one game changer that allows for a longer, ongoing operation involves new, more energy-efficient technology for sequential defrosting coils in spiral freezers.

“We’re doing defrosting in a very unique way with technology that is engineered to mechanically isolate individual coils,” said Peter White, president, IJ White Systems.

“We use coil isolation technology to segregate individual coils that are in defrost,” he continued. “Older, traditional designs required extensive horizontal decking requiring multiple access doors and ladders. This additional internal structure proves to be problematic especially for cleaning and maintenance. Our system is completely open, and we’re isolating our coils sequentially. As one coil needs to be defrosted, it will shut down, and we go through a defrost cycle.”

However, pushing run times to the limit can result in costly failure.

“Some of the biggest causes for unanticipated or unplanned downtime in the freezer is just the nature of the beast itself,” observed Bryan Hobbs, sales and service manager, Ashworth Bros., Inc. “It is a freezer and harsh environment.”

Because many blast freezers are enclosed, with temperatures dipping down to -40˚F or lower, potential problems are often out of sight and out of mind until it’s too late.

“If something should go wrong, the plant may not see it until it becomes catastrophic,” Mr. Hobbs explained.

Still, he added, there are telltale signs when something may be amiss. With a spiral system, a spike in the drive’s power consumption should be investigated immediately.

Related ReadingMeanwhile in coolers, where temperatures are not as brutally cold as in freezers, bakers and snack producers need to keep a close eye on the condition of the belt, noted Craig Bartsch, general manager, belts, IPCO North America.

“The belt surface on both the product and backside is actually a map or a report about how well the belt is performing,” he said. “If there’s wear on the bottom of the belt, something is scraping on it. Maybe the unit is out of alignment or the belt tracker is not working accurately.”

Anthony Salsone, sales engineer, G&F Systems, suggested that a good preventive maintenance checklist includes inspecting all components for wear, ensuring the spiral belt is free from obstructions, verifying all safety sensors are operable and looking at all bearings and rollers for proper alignment and lubrication.

Before ramping up an operation for the day, Erik Fihlman, program manager, bakery and prepared foods for Linde L.L.C., recommended taking a few extra minutes to double check that everything is running properly.

“If you start with conditions that optimize the freezer from the start, you’ll have a much better day at production,” he pointed out. “If you start at suboptimal conditions and begin running product, you’re playing catch-up all day long.”

Linde offers an automatic sequence for startup to monitor belts, blowers and exhaust to ensure they are working as planned before dropping the temperature.

“As a result, when they’re ready for the first products to hit the freezer belt, the freezer is already at optimum condition,” Mr. Fihlman said. “It improves not only performance but also longevity of the machine.”

Although bakers often cannot see what’s going on inside a freezer, a variety of monitoring systems continuously check on a variety of factors to ensure everything is in good order. The Intralox Intelligence system, for instance, keeps an eye on the freezer 24/7 to ensure there are no variances in performance that would lead to downtime, noted David Bogle, global R.&D. director, spiral platform, Intralox. Specifically, remote monitoring tracks belt tension, motors, amperages and other variables to predict issues before the freezer breaks down or damages the belt.

Ashworth offers its SmartSpiral system to monitor key performance indicators and signal to engineers when the freezer might be out of kilter.

“It gives you close to real-time data to predictively plan to make certain repairs,” Mr. Hobbs said.

Linde’s monitoring system relies on a green light to indicate that a spiral or tunnel freezer is operating as expected. The light starts flashing if potential trouble pops up, which allows maintenance to make adjustments without shutting down.

“If you do have an issue that further develops and requires downtime, you know where to look and what to correct,” Mr. Fihlman said. “You know when it happened and what the conditions were at the time. It saves a tremendous amount of time in troubleshooting and executing a fix.”