Products > Pu Foam [Polyurethane]
The steel and the polyurethane are attached by the “FOAMED-IN-PLACE” process, using the machine to inject polyurethane in between two steel sheets coated with zinc and color (Colorbond) in a mold under high pressure. The outer surfaces can be made into waves in order to enhance the strength of the insulator sheet’s structure.
Thickness and Operating Temperature
Recommended thickness of Cheer System ready-made insulator when used at specific operating temperature is as per Table 1
| Thickness | mm | 60 | 90 | 100 | 130 | 150 |
| Heat Transfer efficient | K/cal | 0.33 | 0.22 | 0.20 | 0.15 | 0.12 |
| Suggested operating temp | T 0C | 0 | -30 | -30 | -40 | -45 |
| Limit of use | T 0C | -18 | -35 | -38 | -50 | -60 |
Width
4” 0” (1,219.20 mm.)
Length
Up to 6800 mm.
Properties of the Steel Sheet Outer Surface
The steel sheet outer surfaces that we use is the product of “LYSAGHT”, ORCDQ grade 224 BC Colorbond or the equivalent
product.
Properties of Steel Sheet
See table 2
| Detail | Size (UK) | Size (Metric) |
| Thickness | 0.0248 inches | 0.60 mm. |
| Weight | 1.01 pound/ sq. m. | 4.93 kg. / sq. m. / sheet |
| Elastic Modulus | 3 10-7 pound/ sq. inch | 211 x 10-4 kg. / sq. cm. |
| buckling stress | 9,000 pound/ sq. inch | 633 kg. / sq. cm. |
| Tensile stress | 2400 pound/ sq. inch | 1687 kg. / sq. cm. |
| Expansion coefficient | 64 10-7 pound/ sq. f. | 11.5 x 10-6 cm. /cm. |
| Thickness of galvanized steel | 1.25 ounce/ sq. m. | 300 grams/ sq. m. |
Coating
The outer surfaces are coated with 25 microns silicone modified polyester paint. The paint can be identified as 5 microns of primer and 20 microns of topcoat. The inner surface is coated with 5 microns primer and 8 microns topcoat.
Color
The standard color of the outer surface is white.
The standard color of the inner surface is grey.
Manufacturing Standard
- BSS 1449 - PARTIB - 1962 GRADE CR3 - CR4
- ASTM A366 - 1965T - COMMERCIAL QUALITY
- JIS G3312 - 1987 C GCC - 20 ZINC COATING Z27
| NON-CFC POLYURETHANE SPECIFICATION | ||
| Thermal conductivity | K/cal | 0.020 |
| -0.018 | ||
| Average density | Kg/m3 | 38-40 |
| Resistence to compression | Kg/m2 | 1.6 |
| Higher operating temp. above 0 0C | 0C | 60 |
| Lower operating tem. Above 0 0C | 0C | -120 |
| Fire resistence as per ASTM 1692 | ||
Thermal Conductivity
- Polyurethane Foam thermal conductivity Maximum 0.020 – 0.018 Kcal / m 0hc
Flame Retardant
Polyurethane is a flame retardant NON-CFC
