ADVANTAGES OF FIBRA S.A. PLASTIC DUCTS

Less costly than stainless steel and other traditional corrosion resistant materials, viewed as an installed cost total value.

Their main advantage is their resistance to corrosion, being designed and fabricated for each particular chemical application.

Mechanically resistant, being likewise designed for each particular load applied, with custom made reinforcements both circumferentially and axially.

Very light in weight, this variable being of high importance as it lowers installation and support costs.
Thermically resistant, withstanding up to 100 degrees C with vinylester resins, and up to 160 degrees C if fitted with  fluorpolymer liners.
Low resistance to flow due to its interior smoothness, which in turn lowers the cost in blowers or fans.
Large variety of diameters, ranging from 400mm I.D. to 4,000mm I.D.
Custom-made, which allows configurating duct spools, adjusting them to diverse geometries and dimensions. No limitations imposed by plates, matrixes or geometries.
Abrasion resistance:  where abrasion is present, a thermoplastic liner or hardened FRP can be provided.

FRP Laminates

Fibra S.A. fabricates ducts using polyester or vinylester resins, reinforced with fibreglass of many types: Multidirectional of 450 gr/sq.mt, Bidirectional of 800 gr/sq.mt, Uniº of 500 and 600 gr/sq.mt, and unidirectional roving Tex 2200.  

The glass reinforcement is saturated with catalyzed resin so as to make a dense laminate, complying with the physical and chemical requirements of each application.

In general, the fibreglass reinforcements confer mechanical properties to the laminate and the resins provide the chemical resistance.  All laminates are fabricated and designed for each particular application.

All laminates have a Chemical Barrier, typically made up of one or two Surface Veils of 30 to 40 gr/sq.mt, two to four 450 gr/sq.mt Mats, attaining thicknesses of 2.5 to 5mm. This barrier is  fabricated manually (Hand Lay Up).

On top of that lies a structural barrier, designed to resist loads due to pressure, vacuum, earthquake, its own weight and operational overloads.  This structure can be done by Hand Lay Up or helicoidal continuous filament (Filament Winding).

-For Hand Lay Up the sequence of lamination is of Type II according to RTP1, and is composed of Mat 450/Cloth 800/Mat 450 until design thickness is completed.
-In the case of continuous Filament Winding, it is made up of layers of Roving Tex 2200 and Uniº cloth, wound in helicoidal form with angles of 55º to 80º
-Depending on the magnitude of vacuum, circumferential stiffeners or reinforcements, molded or woven, are incorporated, thus providing axial and circumferential stability.
-Finally an outer layer or top coat, made up of fire retardant resins (FR) with anti-UV additives and pigments is added.
-Chemical barriers are not considered as structural thicknesses.
-Safety factor for pressure:

For Hand Lay Up:  10/1
For Filament Winding:  unit deformation  0.1%
Vacuum safety factor:  5/1

Dual Laminates (Composite laminates):
As compared with FRP, the only change is the chemical barrier, which is made of PEHD, PVC, CPVC, PP, PVDF or ECTFE. The thicknesses of those liners vary from 2.3mm to 5mm, depending on the material and the application.

Fittings:

Flanges, Elbows, Reductions, Tees, Blind flanges, Caps, Lateral outlets and Dumpers are fabricated. All these fittings are designed and dimensioned for each case so as to comply with the requirements of each application.
As an example, the table below shows Flange dimensions for gas ducts according to Lurgi standards.

Dimensional Table for Duct Flanges