Spiral cooling and freezing systems have an unmatched capability to save space. For process consistency,
they must also ensure even temperature distribution, and an uninterrupted conveying movement for minimum downtimes, while being easy to clean and maintain. Energy efficiency and scalability features are also important checkboxes for a reliable piece of equipment.
Several types of cooling and conveying systems can be adopted, to automate controlled-temperature processes – from proofing to cooling and freezing. To maintain or even improve the quality of the products, in increasingly faster production setups, customization is key to ensuring process optimization. This is especially true in industrial bakeries. For AMF Bakery Systems the reliability of the line is crucial to every project, big or small, so the design and technology offered need to be simple, robust, yet highly customizable.
Looking at the big picture of a production setup and then ‘zooming in’ to the spiral solution helps to evaluate the cooling process needs in the context of the entire line, in terms of timings, volumes, speeds and space required. The flow of the line and the placement of equipment within a facility are critical considerations. To meet these requirements, AMF designs highly customizable solutions in terms of configuration and size. “We assess the flow of products entering and exiting our systems to ensure consistent handling. This approach not only reduces downtime for our solutions but also for downstream equipment. The precision in spiral manufacturing and the quality of product transfers, tailored to the shape of each item, ensure proper alignment throughout the line, for enhanced productivity,” AMF specialists explain.
Smart systems
The AMF Spirals are highly automated to ensure continuous operation during production without the need for operator supervision. This system also ensures that the spirals continue to operate for as long as possible during downstream stoppages. Incoming products are monitored and the progress is displayed on the HMI, allowing for real-time tracking as they travel through the spiral. In addition to monitoring the products passing on the conveyors, the take-up motor output torque is being constantly monitored. “Through finetuning calculations, the motor’s speed is regulated to follow the main drum and keep the belt tension as low as possible, yet always tightly engaged to the drum. Special routines may apply with our spiral freezers to allow safe operations when the spirals encounter ice buildups,” AMF explains.
Various sensors—including those for vibration, temperature, humidity, and motor parameters from the variable frequency drives (VFDs) – provide comprehensive insights into the operating conditions of the spirals. This data facilitates preventive maintenance and enhances quality control efforts.
Vesta spirals can combine technology creatively in setups for cooling and freezing configurations to minimize floor space while making full use of available ceiling height. AMF specialists illustrate: “We have, over the years, designed unique concepts to accommodate building restrictions or process requirements. From sizes that fit in a home garage to very large diameters and tall spirals containing thousands of meters of belt, we can connect many spirals together, even at odd angles, to avoid building obstacles.”
Optimizing the belt width with engineered feeding conveyors can also save considerable floor space (e.g., double pass spirals, or custom configurations that feed products into the spiral at different heights, or on the turning belt).
Spiral systems quite literally revolve around the conveying belts, so the adequate type and belt material for specific needs should be identified for each bakery, according to its product needs. Considering that they often come into direct contact with the products, which may, sometimes, be sticky, determines how this major component of a spiral system should look. AMF developed an extensive array of belt choices that can be incorporated in a spiral cooler/freezer: “Most of our features and options are available with every belt, allowing customers to freely choose, based on their preferences,” its specialists say.
Process controls: spiral proofing and cooling
The path to customizing and designing a technology concept is found together with the bakery. The conditions that need to be met for the targeted product quality determine custom builds. This means the exact temperature and humidity desired must be reached and maintained, regardless of daily or seasonal weather. “For Vesta Spirals, this primarily involves determining the optimal duration for the product to remain in an environment that maintains consistent temperature, humidity, and airflow,” the specialist illustrates. AMF Vesta’s spirals are optimized to meet any traveling time required, so that the product can rest while traveling through the spiral as long as it needs, while matching the production rates.
The humidity of the spiral proofer is mainly controlled through a gentle stream of steam added to the circulating air. Ventilation ducts will distribute the warm and humid air along the entire length of the enclosure. All ducts are stainless steel, with a slopped top and accessible for sanitation.
To ensure the desired cooling/humidity effect throughout the product’s time in the spiral cooler, AMF focuses on configuring the space to position fans and cooling coils in a way that provides optimal airflow around the products. Specific solutions are tailored to each design if needed, including the controlled intake of fresh air to effectively balance humidity levels, the specialist explains.
Spiral freezing
The Vesta Spiral Freezer uses the Blast Freezing System, with an enclosure designed to sustain the required airflow without blasting air directly onto the products, which would cause unwanted displacements. “Deep-freezing products often require heavy air movement. The enclosure subdivision, the fan and coil positions are a key feature in accomplishing a gentle yet rapid freeze, with a uniform and continuous airflow around each product,” the specialists highlight. It features an automatic defrost-while-running sequence. The defrost time may vary from one system to another, but the sequence is always planned so that one coil can defrost, dry and spring back into operation before another one can initiate its own defrost cycle, with no influence over the system’s overall freezing capacity. “Cascading from one coil to another results in the uninterrupted operation of the Blast Freezer,” AMF notes.
Choosing the right refrigerant solution can also be flexibly selected: AMF can accommodate any commonly used refrigerants in the industry. Every system is analyzed with care, considering existing installations but also the cost and advantages of a new system. It is an integration challenge that is solved together with each manufacturer.
Sanitation and hygiene: built-in
Operating the machine is another important consideration. This is why the ease of maintenance and cleanability are crucial factors in the design of spiral systems. AMF spirals can be fitted with various access platforms to facilitate reaching the top conveyor or accessing the center drum. Additionally, “We provide automatically controlled oilers that activate only when necessary, minimizing usage and eliminating the need for manual intervention. Our programmable wash cycle, complete with a dedicated belt washer, enables effective cleaning of the product contact surfaces with minimal manual effort,” AMF specialists explain.
The Vesta spirals are designed to prioritize sanitation: the spiral structure itself is primarily built with open-frame components, preventing dirt accumulation and bacterial growth. This design allows for easy access and cleaning while ensuring that water does not collect. In addition, the patented cages are designed with single bars rather than having caps over a support beam, to further minimize areas where bacteria could build up. “Our mono-piece cage bar design was developed to achieve exceptional cleanability. While traditional designs typically use plastic caps over a metal support beam, AMF has innovatively created a single-piece component that functions equivalently to caps, while being significantly more sanitary. Given that access to the cage bars is often restricted and in close proximity to the product, ensuring high sanitation standards is even more critical,” the technology developers explain.
AMF Bakery Systems specialists
The belt washer-and-dryer system also optimizes hygiene by integrating high-pressure water nozzles that cover the whole width of the belt, top and bottom. AMF explains how cleaning is carried out with minimum hassle: “Top and bottom air knives, which can also be easily opened and deep cleaned, will keep water drips coming out of the washer to a minimum. An easily programmable wash cycle can predetermine how many passes in the washer are required – often, one is enough – to meet higher cleaning standards.” Each spiral has its own wash box, so no installation is required to do the cleaning; all the preparation required is connecting the provided hoses from the pump and blower unit.
Continued consistency
Determining the right setup of the spiral system guarantees it will operate reliably and with optimum efficiency, for the exact product recipes, at the exact production volume and speed. The ease of use and of maintaining them are also optimized with new improvements, to meet the highest hygiene standards with the shortest possible time off from production. The prerequisites are met, for round-the-clock production.
