Sandwich PU Roof Panel

"World's Best Manufacturing Process with a continuous Production line for Sandwich PU/PIR Sandwich Panels."
Metal-faced polyurethane sandwich panels are the system of choice today for large industrial buildings refrigerated warehouses, office blocks, exhibition halls, fair pavilions, schools, and sports halls. The aluminum or steel facings themselves are surface coated and can be manufactured with profiles of various depths leading to a higher load-bearing capacity. Polyurethane sandwich panels come complete with specially formed tongue-and-groove joints ensuring a perfect fit and maximum integrity, Assembly is fast, easy, and cost-effective. As a result, these thin, relatively lightweight sandwich panels can safely bridge wide spans.

Alfa Sandwich Panels Manufacturing Process

The top and bottom coil (sheet metal) are clamped onto the plants unwinding unit and fed into the machine. In the first step, “corona system” cleans both reverse sides of the sheet metal using high frequency to remove greases and dirt and to guarantee the best possible subsequent full spread adhesion between foam and sheet metal. Thereafter the protective films are rolled onto outside of both metal sheets. The sheets are then brought together, the bottom sheet is foamed by the swinging foam head and the top sheet is mechanically steadied. Immediately after that, the panel is fed into the heated drying tunnel where the foam expands to its full volume, binds to the sheets and transforms both sheets to one robust, shear resistant composite structural panel. After leaving the tunnel the panels are cut according to your specification using flying saw/cutter.


Panel thickness available 30mm, 40mm, 50mm, 60mm, 80mm, 100mm, 120mm
Panel width available 1060mm
Panel length available 2000mm-12000mm
Average density 40± 2kg/m
Thermal conductivity 0.024-0.03 W/m
Temperature range -40+800C
Free from CFC CFC free
Type of foam B1, B2, B3, PIR
Heat transfer co-efficient -0.022W/M2*k
Pressure 0.10Mpa
Cubic Area Change =1%(-30 C – 100 C/96h)


  • High load bearing capacity at low weight.
  • Excellent and durable thermal insulation.
  • Capacity for rapid erection without lifting equipments.
  • Easier installation in hostile weather conditions.
  • Easy repair and replacement in case of damage.
  • Long life and very low maintenance cost
  • Good sound insulation
  • Reasonable fire reaction and resistance
  • Cost Savings
  • Tongue and groove type joinery system.
  • Hidden self tapping screws for aesthetic appeal.
  • Great energy saver.
  • Fast and easy installation.
  • Light weight.
  • Space saving.
  • Various designs.vivid colours.
  • Energy conservation as per ECBC code.
  • Easy Applications.


  • Industrial Buildings.
  • Partitions-Semi Glazed.
  • Commercial Buildings.
  • Warehouse/Godown.
  • Cold storage/Blast Freezers.
  • Farm House.
  • Pharmaceutical Manufacturing units.
  • Air Handling Units.
  • Poultry Form.
  • Dairy industry.
  • Malls/Departmental Stores.

Energy Efficiency

With 80 mm thick sandwich panels with polyurethane rigid foam, the U value is 0.297 W/(m K). In comparison, a solid wall with 24 cm thick masonry and 2 cm plaster walls has a U value of 1.85 W/(m K).
Rigid polyurethane foam combines excellent thermal insulation properties with good mechanical strength, making it an outstanding construction material that does not rot, mold-resistant, odorless and non-toxic for all conceivable applications, the foam is resistant to the chemicals typically used in construction and is compatible with most solvent-containing adhesives, paints and wood preservatives. Polyurethane rigid foam is extremely durable and can be installed easily and securely, ensuring cost-effective, efficient construction.

puf panels energy Efficiency

Section Properties

Puff (0.5/0.4) steel panel 550 Mpa
puff thick (mm) Weight kg/m2 Area cm2 Ix& cm4 ZX-Top cm3 ZX-Bottom cm3 Ma (top) Kn.m Ma (bottom) Kn.m
30.00 8.38 10.67 51.13 11.19 21.48 4.061 7.798
40.00 8.42 10.72 73.52 14.76 24.75 5.359 8.986
50.00 8.50 10.83 101.10 18.76 28.40 6.809 10.309
fy= 55 Kn/cm2
E= 2.00E+08 KN/M2