Refrigerator Cabinets

A typical refrigerator appliance cabinet consists of an outer metal cabinet, an inner plastic liner, typically made from ABS or HIPS, and an insulating polymer foam core, typically a poly(urethane) (PU) foam (29). 

Some of the common blowing agent substitutes currently proposed for insulation-type foams used in refrigeration appliance cabinets are 1,1-dichloro-fluoroethane (HCFC-141 b), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123), and 1,1,1,2-tetrafluoroethane (H-FC-134a). 

The use of a protective polymer film as barrier has been proposed. This barrier consists essentially of a thermoplastic poly(ester) resin, which is a homopolymer or copolymer adduct of an aromatic dicarb-oxylic acid in an active hydrogen-containing material. However, this poly(ester) resin copolymer has a poor compatibility with styrene resins. Thus, the protective polymer film lacks the desired regrind capability. 

During the manufacture of appliance cabinets, a thermoplastic synthetic resin sheet, usually made of PS, is either co-extruded with a barrier layer or laminated to a barrier layer to make the inner liner. To successfully recycle the trim or scrap, the protective polymer film 

Other proposed compositions are double layer films, including an inner film containing a copolymer of ethylene vinyl acetate and an outer film containing a copolymer of ethylene and acrylic acid. The purpose of the outer film, however is to improve the adhesion between the PU foam and the outer film. In contrast, the inner film effectively provides a stress relief layer. 

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Part 2 1985. Specification for PUR Foam for Use in Refrigerator Cabinets, Cold Rooms and Stores, 12 pp... 

FROST FREE REFRIGERATOR - Refrigerated cabinet which operates with an automatic defrost during each cycle. 

NO-FROST FREEZER - Low-temperature refrigerator cabinet in which no frost or ice collects on freezer surfaces or materials stored in cabinet. 

Lu, W. Tassou, S.A. Characterization and experimental investigation of phase change materials for chilled food refrigerated cabinet applications. Appl Energ 112 (2013) 1376-1382. 

The energy consumption reduction in two refrigerator cabinets, each using one panel, 100 X 50 X 2 cm large, covering 40% and 60% of the total surface is shown in Table 4.11. The same assumptions used in Table 4.10 have been made for the PU thermal conductivity and thickness of the barrier foil. 

Supermarkets lose many millions of dollars each year due to stock losses from refrigerators in their stores. A typical supermarket may contain more than one hundred individual refrigerated cabinets, cold store rooms and items of plant machinery which interact as part of a complex integrated refrigeration system within the store. Things very often go wrong with individual units (icing up of components, electrical or mechanical failure, and so forth...) or with components which serve a network of units (coolant tanks, piunps, compressors, and so on). 

Appliance manufacturers (refrigerator cabinets, as well as many others) Sectional garage doors made of prepainted and wood-grain embossed steel. Commercial and residential shelving of all types. 

A refrigerator works on this principle. Heat is taken out of the food cabinet, compressed and passed on to the heat exchanger or radiator at the back of the fridge. This warm air then radiates by air convection currents into the room. Thus the heat from inside the cabinet is moved into the room, leaving the sealed refrigerator cabinet cold. 

Use of this more environmentally friendly alternative may be facilitated for manufacturers of domestic appliances following the introduction of new safety features in the CycloFlex and LinFlex systems for refrigerator cabinet production. Hennecke Machinery has developed a comprehensive safety system for pentane-based foam production, meeting many of the reservations of US manufacturers of PU board. 

Dry stores The options show optimum widths of rooms to maximize linear storage per square meter. Refrigerated stores Enclosures are normally modular and formed in 75mm/3"thick panels. In smaller kitchens refrigerated cabinets could replace cold room enclosures. 

Thus the heat from inside the cabinet is moved into the room, leaving the sealed refrigerator cabinet cold. 

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