Protection of circular horizontal sheet metal ventilation ducts with Fibrogaine®

DUCTS TESTED ACCORDING TO NF / EN 1366-1 – CLASSIFICATION ACCORDING TO NF / EN 13501-3

Montage des conduits

Area of validity

  • Circular horizontal ducts
  • Duct diameter between 0 and 1,000 mm
  • Maximum section length: 3,000 mm
  • Duct sheet metal thickness
  • Maximum centre-to-centre spacing of support systems: 1,200 mm
  • FIBROGAINE®  density: 247 kg/m3 ± 15 %
Principe de supportage

Duct installation Principle

The duct is composed of sections with a maximum length of 3,000 mm.
These components are joined with a 300 mm wide sleeve attached to the sections with 4.5 x 16 mm self-tapping screws spaced 200 mm apart around the perimeter of the duct.
The section joints are sealed using an A1 acrylic sealant. The duct body is supported with 1.20 m spacing (see diagram 1).

The support system is composed of (see diagram 2):

  • Ø 630 mm : two half-brackets attached together by M6 nuts and bolts and supported in the centre by a single threaded rod.
  • Ø 1 000 mm : two half-brackets attached together and supported on each side by a threaded rod.

Protection installation principle

  • A first layer approximately 30 mm thick of FIBROGAINE® is applied to the duct (without primer).
  • A 25 mm hexagonal grate (Ø = 0.8 mm) is then installed all around the duct.
  • A second layer of FIBROGAINE® is applied to achieve the desired final thickness.

Protection of support systems

The half-brackets are contained in the duct body protection. The threaded rods can be protected by a rock wool shell (30 mm, 65/70 kg/m3) as well as FIBROGAINE® or by installing a grate and applying FIBROGAINE®. In both cases, the total thickness of the protection (shell + FIBROGAINE® or FIBROGAINE® only) will have a thickness identical to that applied to the duct.