Commercial Refrigeration Design and Construction
Purchasing a commercial refrigerator can be a difficult task, since you have to determine which type of commercial refrigeration fits your needs, what capacity is required, and where in your workflow it should be installed. In order to choose the best commercial refrigerator for your business, it will also benefit you to understand the materials commonly used in the interior and exterior construction of commercial refrigeration units, as this can affect the unit's durability, maintenance requirements, and price point.
Metals Used in Commercial Refrigeration
There are several types of metal commonly used in the construction of commercial refrigeration, including aluminum, cast iron, chrome, copper, and steel. The two types of metal most often used on the interior and exterior of refrigeration equipment are aluminum and steel. These metals are made in multiple grades, or series, each of which contains different components that determine the metal's properties.
Aluminum vs. Steel
Types of Aluminum
According to the Aluminum Association, aluminum alloys can be divided into three categories: commercially pure aluminum, heat-treated alloys, and non-heat-treated alloys. Aluminum alloys are created by adding certain elements (copper, iron, magnesium, manganese, and zinc) to an aluminum base. The resulting alloys are stronger than commercially pure 1100 aluminum, making them better suited for manufacturing commercial equipment that needs to stand up to use in hectic foodservice operations.
In refrigeration, non-heat-treated 3003 and 3004 aluminum alloys are used, as is anodized aluminum, which is given a more durable finish with a layer of protective oxidation.
Types of Steel
The most common type of steel used in commercial refrigeration construction is stainless steel. This includes 300-series stainless steel, an austenitic alloy of at least 16 percent chromium, no more than 0.15 percent carbon, and nickel, and 400-series stainless steel, which is made with a larger amount of carbon. The more carbon a stainless steel grade contains, the stronger it is. The most commonly used types of stainless steel for refrigeration equipment are 304, 316, and 430.
Another type of steel found in commercial refrigeration is galvanized steel, a metal created by coating regular steel with zinc. Galvanized steel is not as strong as stainless steel, so it is frequently only used on the less vulnerable sections of a unit's exterior, such as the top, bottom, and back.
Chrome, copper, and cast iron, an iron-carbon alloy, are used in the manufacturing of components found within commercial refrigeration units. For example, some systems use cast iron evaporators, shelf clips may be plated in chrome, and copper may be used for tubes and wiring.
To learn more about the maintenance requirements and manufacturing methods for the metals discussed here, check out our general guide to food-grade metals.
Some manufacturers use ABS plastic, a lower-cost material that offers impact and corrosion resistance but is not as durable as aluminum or steel. ABS is often used in foodservice applications, but in refrigerated units, you will find it used for interior cabinet and door liners.
Many of the racks and shelves that come standard with commercial refrigeration equipment are made of a metal that has been coated in PVC, polyethylene, epoxy, or another plastic so they are easier to clean.
Refrigeration units are usually insulated with foamed-in-place polyurethane, a polymer that does not contain now-banned CFCs (chlorofluorocarbons). The amount of the high-density insulation provided varies among manufacturers.