HOW TO SPECIFY A ROLLER CONVEYOR FOR A FREEzer APPLICATION.

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1 blog.hytrol.com hytroltv.com us.viastore.com HOW TO SPECIFY A ROLLER CONVEYOR FOR A FREEzer APPLICATION. In a pallet handling situation, sub-freezing temperatures can create the need for specialized equipment that is able to effectively and reliably operate. To choose a conveying solution for your needs, first know your product; then, know the high and low temperature ranges of the product needing to be transported.

2 Products Right for Pallet Handling Conveyor If you have large product, heavy product, or palletized product, you can apply a pallet handling system ready for both transport and accumulation. Pallet handling systems can accommodate products up to 100 wide. Standard loads are up to 3000 pounds. Complete pallet handling systems achieve needed output, safeguard the handling of product, and create a safer environment for employees by dealing with less moving equipment. If a pallet handling system is the correct application for your product, make these choices for the best possible solution. 2

3 Stay Away from Pneumatics While still sometimes used in warmer environments, the implementation of pneumatics in a freezer environment is not ideal based on dew and frost points. The dew point is the temperature at which water vapor in the air condensates into liquid, and changes with the relative humidity and air temperature. Dew point can be calculated with the following formula, where Tdp is dew point, T is relative humidity, c is temperature (in Celsius), and RH is the Magnus formula. A chart of dew point in reference to Air Temperature and Relative Humidity is shown below. Dew Point 122º 104º 86º 68º 50º 100% Humidity 80% Humidity 60% Humidity 40% Humidity 20% Humidity 32º 14º -4 º 32º 41º 50º 59º 68º 77º 86º 95º 104º 113º Air Temperature 3

4 At a Relative Humidity of 70%, a temperature of 95 degrees Fahrenheit yields a dew point of 82.4 degrees. As the temperature decreases, the condensation of water vapor becomes more rapid, although there is less total condensation in the air. At -13 degrees Fahrenheit, the dew point is -20 degrees Fahrenheit. In addition, the frost point appears in temperatures lower than 32 degrees Fahrenheit. At the same dew point of -20 degrees, the frost point is -26 degrees, and some of that condensation will turn to frost. The takeaway: for the condensed air of a pneumatic conveyor to work in a refrigerated system, a costly dehumidifier must be put into place so that frost does not harm the conveyor s pneumatic system. 4

5 Instead of applying a dehumidifier, consider an electric-powered pallet handling conveyor that disposes of the need for pneumatics. Electric conveyor can be used for transport and can accumulate items with zero back-pressure. The standard motor for Hytrol s electric conveyor, the CREZD, is rated to -13 degrees Fahrenheit, as is the standard lubrication. If your operation requires a lower temperature rating, your supplier should be able to accommodate you. Eliminate Chains and Lubrication When Possible Most electric conveyor ships standard with a high-carbon chain. While chain conveyor works well, it needs to be lubricated. In cold environments, maintaining the equipment with this lubrication is costly and difficult. For these situations, the conveyor can easily be equipped with a Poly V power transmission belt. The Poly V is a ribbed belt that creates a large contact surface area, and is ideal for 5

6 freezer applications with high ratio drives over shorter distances. The Poly V eliminates the need for lubrication and maintenance associated with a chain; Hytrol s is rated down to -22 degrees Fahrenheit and can handle an extreme temperature range. A Poly V belt can also lessen the costs of preventative maintenance over time. For a solution that requires a chain, use a stainless steel chain with the proper rated lubrication; note that the chain does reduce the capacity of the equipment. Specify Your Starter Box, Roller Bearings, and PLC The standard motor starter is rated to 23 degrees Fahrenheit. For applications needing a lower temperature, specify the temperature rating with your integration partner. Roller bearings are rated to a temperature of -40 degrees Fahrenheit and can be shipped standard with the product. 6

7 It is wise to pair an electric conveyor with a programmable logic controller (PLC), or other means of zero-and minimum-pressure accumulation. The Hytrol CREZD works with its EZLogic, which is rated to -13 degrees. EZLogic combines the sensing accuracy of photo-electrics with discrete logic control without the use of a PLC or pneumatic logic components. This gives the system higher reliability, higher throughputs, and ease of maintenance for a cold storage environment. Most programmable logic controllers use either a retro-reflective product sensor and reflector or a diffuse type. If below -13 degrees, use a programmable logic controller and photo eyes for the accumulation of products. 7

8 Other Considerations As with any conveying solution, the user must determine their longterm goals before installing the proper equipment. For example, a premium efficiency motor in any environment, while costing more up front, will extend the life of your system while decreasing maintenance and energy costs. When choosing equipment, higher initial costs may be compensated for by lowering the total cost of ownership over time. In Conclusion When working with a system running down to -13 degrees Fahrenheit, use an electric-powered handling conveyor solution with programmable accumulation system, a Poly V drive system, and standard motor, while changing to a low temperature starter box. 8

9 About Hytrol Conveyor Company, Inc. Hytrol Conveyor Co., Inc. designs and manufactures innovative conveyor equipment, controls, and solutions for customers with processing, manufacturing, warehousing, and distribution needs. Hytrol s 27,000 square foot Technology Center is the birthplace for many industry-changing solutions, such as EZLogic accumulation conveyors and the E24, a low-voltage, motor driven roller conveyor series. These technologies are complemented by Hytrol s sortation offerings, the ProSort 400 Elite series highspeed shoe sorter, as well as the ProSort MRT series narrow belt sorter. Hytrol s consistent growth is strengthened by its Integration Partner Network, with over 100 locations worldwide. Experience the Hytrol Advantage today! For more information, please visit: blog.hytrol.com

10 About VIASTORE SYSTEMS For over 40 years, viastore systems has been a leading international provider of automated material handling solutions including AS/RS (automated storage and retrieval systems) and conveyor systems, warehouse management systems software, material flow and process controls, and integrated SAP logistics solutions. The company employs over 450 people worldwide and has annual sales of over $207 Million. For more information, please visit: us.viastore.com