How Circular Conveyor Buffer Systems Keep Snack Food Packaging Lines Running
How Circular Conveyor Line is Used in Snack Food Buffer Conveyor in Food Packaging?
What a Circular Conveyor Buffer Does on a Snack Packaging Line
A circular conveyor buffer sits between two machines on a snack food packaging line. It absorbs the speed gap between them. Upstream, a frying or baking process feeds product onto the line at a steady mechanical rate. Downstream, a flow wrapper or multihead weigher pulls product off at its own fixed cadence. Consequently, any short stop on either side creates a mismatch. As a result, the rest of the line must handle that mismatch somehow. Engineers install a circular conveyor buffer, also called a rotary accumulation table, at exactly that gap. In turn, the closed-loop conveyor track holds a rolling reserve of chips, crackers, or extruded snacks. This reserve keeps the line moving during a minor jam. Consequently, operators avoid full-line stoppages for routine faults such as a torn film reel or a blocked chute.
Inside the Mechanism: How the Circular Conveyor Handles Snack Flow
The circular conveyor buffer works as a continuous motion conveyor shaped into an oval or full circle. A belt or a series of carrier pucks travels around the track. In turn, the control system adjusts belt speed in real time. When the downstream flow wrapper infeed slows, incoming product accumulates on the buffer. Notably, it does not pile against a stalled line. Meanwhile, the belt keeps circulating. As a result, fragile snacks stay clear of crushing loads. Photoelectric sensors along the track also measure product density. Then, they send a signal to a PLC. The PLC then raises or lowers belt speed to hold a target accumulation level. Therefore, the buffer neither starves the downstream machine nor overfills the loop. Most snack lines run this setup as a FIFO buffer conveyor. Specifically, the first piece onto the loop becomes the first piece off it. This sequence also protects batch traceability, a detail auditors check closely during food safety inspections.
Key Design Parameters Engineers Must Set
Before installation, engineers size the circular conveyor buffer around three factors. Specifically, these factors are dwell time, belt speed range, and product footprint. Dwell time determines how many seconds of production the loop can hold during a stoppage. In addition, belt speed range sets how fast the buffer can drain once the downstream machine restarts. Product footprint decides pocket spacing and lane width. For example, a delicate cracker needs more clearance than a compact pretzel. For clarity, Table 1 lists the parameters a typical product accumulation system must define during layout.
Design Parameter
Typical Range
Function
Dwell Time 30 - 180 seconds Sets how long the loop holds product during a stoppage Belt / Track Speed Range 5 - 40 m/min Lets the buffer drain quickly once the downstream machine restarts Track Diameter 1.2 - 3.5 m Determines total loop length and storage capacity Pocket / Lane Width 40 - 150 mm Matches carrier spacing to snack piece size Drive Type VFD-controlled AC or servo motor Delivers smooth speed changes without product surge Table 1. Core design parameters for sizing a circular conveyor buffer on a snack food line.
Circular Conveyor Buffer vs Other Accumulation Methods
Snack packaging lines use several accumulation methods besides the circular conveyor buffer. For comparison, Table 2 places the three most common options side by side. In turn, engineers can match the mechanism to the product. Buffer Type Flow Pattern Floor Space
Best Fit
Circular / Rotary Accumulation Table (TallMan Robotics) FIFO closed loop Moderate, ground floor Round or irregular snack pieces, retrofit lines Recirculating (Bi-Flow) Table Two-direction flow Larger footprint Mixed batch re-feed applications Vertical Spiral Buffer Vertical FIFO Small footprint, tall Height-clear plants with limited floor space Table 2. Accumulation method comparison for snack food buffer applications. A rotary accumulation table handles round or irregular snack pieces well. Specifically, the circular path applies gentle back pressure control against product edges. In contrast, a recirculating table works for two-direction flow. However, it also needs more floor space for the same dwell time. A vertical spiral buffer saves floor space and adds height instead. Consequently, some plants cannot fit that extra height under existing ceiling clearance. For that reason, plant engineers choose the circular layout most often for ground-floor retrofit projects.
Real Case Studies: Circular Conveyor Buffers in Snack Production
Quantified results from published case studies show why manufacturers add this buffer stage. For instance, FlexLink's accumulating conveyor line uses the same closed-loop principle as a circular buffer. It balances flows at rates up to 1,000 products per minute across reported food packaging installations. Similarly, Cavanna Packaging Group documented a cookie packaging system. That system keeps a flow-wrap line running at 130 packages per minute, with each pack holding up to 32 cookies. In addition, Enstrom Candies replaced a hand-fed toffee line. The old line topped out near 200 pieces per minute. By contrast, the new buffered and automated system now runs almond toffee petites at 700 pieces per minute. This upgrade also cut product and packaging loss by 60 to 70 percent, according to reporting on the project. Overall, these figures show a properly sized buffer stage raises sustained throughput. Notably, it does more than simply prevent downtime.
Integrating the System with Upstream and Downstream Machines
A circular conveyor buffer only performs well when engineers link its controls to the rest of the line. Specifically, the buffer's PLC must exchange speed and fill-level signals with two other controllers. These are the upstream oven or fryer controller and the downstream flow wrapper drive. For example, the flow wrapper may stop for a film splice. In response, the buffer signal tells the oven line to slow down gradually instead of stopping abruptly. This gradual response protects product quality. Otherwise, a sudden halt on a frying line can scorch product still sitting in the fryer. Sanitary design also matters for snack applications. Specifically, stainless steel frames, open belt structures, and tool-free belt removal let plant staff wash down the accumulation table between shifts. As a result, the circular conveyor buffer supports continuous throughput. At the same time, it also meets the strict cleaning schedule that snack food plants must follow every day. References - FlexLink accumulating conveyor performance data, Vertical Accumulators category, PMMI ProSource Directory. https://www.prosource.org/category/conveying-feeding-and-handling/accumulators/vertical-accumulators - Case Study: Cookie Packaging Machine Maker Gains Flexible Feeders, Automation.com. https://www.automation.com/en-us/articles/july-2021/case-study-cookie-packaging-machine-maker-feeders - Enstrom Increases Throughput With Cavanna's Automated Flow Wrappers, Cavanna Packaging USA. https://www.cavanna-usa.com/how-enstrom-increased-production-with-cavannas-automated-horizontal-flow-wrappers/ - Snack Food Packaging Solutions, Cavanna Packaging USA. https://www.cavanna-usa.com/snack-food-packaging-machines/ - Accumulators, PMMI ProSource Directory. https://www.prosource.org/category/conveying-feeding-and-handling/accumulators You are welcome to visit our other social media or video gallery as follows: Youtube: https://www.youtube.com/@tallmanrobotics Tiktok: https://www.tiktok.com/@tallmanrobotics Facebook: https://www.facebook.com/tallmanroboticslimited Linkedin: https://www.linkedin.com/in/tallman-robotics