RAYCHEM RDSS RAYFLATE BAGS
Description
Unsealed cable pipes and ducts need not to cause dampness and flooding in substation basements, cable vaults and access manholes. In these environments rust, corrosion and a humid environment inevitably result in damage to support structures, metal work and electrical
equipment. The most common route for water to enter into such installations can be blocked simply and effectively by a field proven technique developed by Raychem.
The Rayflate Duct Sealing System (RDSS) has been designed for use on power cables to provide a watertight seal when used with plastic, concrete or steel ducting systems.
Once installed the Rayflate duct seals can provide operators with immediate access in clean and dry conditions, eliminating the routine of
pumping manholes dry before work can begin.
Clean, fast, easy sealing method
The Rayflate seal consist of an inflatable bladder of flexible metallic laminate, coated on both sides with a sealant strip. With the sealant strips lubricated, the product is simply wrapped around the cable and easily slides into the duct. The bladder is then inflated with a gas
pressure tool which presses the sealant coating against the duct wall and the cable. Upon removal of the filling tube, an automatic gel
valve system reliably retains the gas pressure in the Rayflate duct seal. The entire installation is performed within a few minutes – even in
congested enclosures – without any messy or installer-sensitive mixing and filling.
Seals vacant and multiple cable ducts
Depending on the duct diameter, most Rayflate bags seal vacant ducts and ducts which contain up to two cables. Sealing of three or more
cables can be easily achieved by merely inserting a mastic sealant-clip between the cables. The RDSS-Clip is made from a high-temperature
mastic mounted on an installation stick.
Versatility
As the Rayflate system adapts itself to most configurations, the system is independent of duct ovality. Each Rayflate seal covers a large range of cable and duct diameters.
Ideal for both new and existing cable installations
The versatility of the wraparound concept enables use not only for new cable installations, but also for existing applications. Unlike other
methods that require dry ducts, the Rayflate seals can be installed when water is still flowing out of the duct thus saving valuable installation time.
Removable
Rayflate seals are easier to be removed from a duct or a pipe than other systems. This allows cables to be replaced in an upgrade or repair. Since ducts are not damaged by the Rayflate system, they can easily be sealed again.
Performance Tested
Rayflate duct seals are a result of our long involvement in sealing and corrosion protection technologies.
Extensive testing at room temperature has shown water and air tightness at static pressures of more than 0.3 bar, even in conjunction with cable bending, vibration, torsion and axial pull. Resistance to common chemicals has been proven by immersion tests.
As the Rayflate system is specially designed for power cables, it was tested with cables load-cycled at conductor temperatures of 90°C,
similar to specifications required for cable accessories. The sealing tests showed water and air tightness with internal duct pressures of 0.3 bar with single and multi-cable configurations. A detailed test report is available.
Lifetime calculations indicate that a typical Rayflate duct seal will withstand a 3 m waterhead for 30 years after installation. These results are based on typical utility cable loads at average ambient temperatures of 25°C and diffusion rate measurements at elevated temperatures and after ageing by load-cycling. The sealing performance was confirmed by sealing tests with reduced internal bladder pressures
