Inflatable Duct Seals For LV HV Cable Ducts, Conduits & Substation Entries

By Chris Dodds on 7th July, 2016

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Inflatable Duct Seals For LV HV Cable Ducts, Conduits & Substation Entries

Inflatable Duct Seals For LV HV Cable Ducts, Conduits & Substation Entries

Sealrad is a system used for sealing cable ducts and pipes when the cables and equipment need protecting from water leakage or humidity - the workers require a safe environment for working and to avoid the risks that occur with the penetration of gas and/or dangerous fluids at the workplace.

The Sealrad system is cost effective as pumps are used for emptying the water and disinfestations in the workplace.


The Sealrad Inflatable Cable Duct Seal System:

  • An inflatable sealed envelope based of flexible laminate metal / plastic
  • Two strips of mastic sealant applied on each side of the envelope
  • Inside the envelope there are reagents which putted in contact, through a simple pressure using your fingers, it activates a natural reaction developing gas causing the swelling of the envelope

Sealrad System

Inflatable Duct Seals - Sealrad Applications

  • Seal conducts from seepage of gas and water in the nodes of the underground networks such as: telephone networks, MV-HV substations and elecrical substations and cable tray
  • Suitable for plastic pipes, concrete and steel
  • Seal empty conducts or filled by one or more cables including, medium and high voltage

Inflatable Duct Seals - Sealrad System - Features & Benefits

  • Self-inflatable, so there is no need of installation equipments (ie. manual inflator, pressurized cylinder, etc.)
  • There is no need to measure pressure and no pressure gauge
  • The duct seal does not produce residues to send to landfill
  • The operation does not depend on the skill of the worker or from the installation conditions
  • Quick and easy to install, clean and non-toxic cable sealing 
  • The seal adapts to ducts that have a oval shape
  • Applicable on cables with sheath/jacket in PVC, PE, Pb o Al
  • Applicable to a wide range of cable ducts with a single size
  • Resists up to 5 meters of water column (0,5 bar)
  • Resists environmental aggressions (chemicals, bacteria, salt, mushrooms, etc.)
  • Allows natural movement of torsion of the cables
  • Easy to remove cable duct seals

Inflatable Duct Seals For LV HV Cable Ducts, Conduits & Substation Entries Installation Guide

1. Empty cable ducts or filled by 1 or 2 cables/wires:

Lathering strips of mastic, wrap around the cable, crush with two
fingers where indicated in the corner and insert into the conduct.

Empty ducts or filled by 1 or 2 cables/wires:

2. Cable ducts with 3 or more cables/wires:

Insert between the cables a spacing diaphragm sealant (Sealclip)


Ducts with 3 or more cables or wires


Pierce the envelope with a screwdriver and pull it out with pliers



About Elcon Megarad

Elcon Megarad is the Italian leader that designs, produces, tests and markets power cable accessories and components for low, medium and high voltage and has been since inception in 1981. Operating internationally the company has a passion for research and technological innovation.


  • Further reading

Elcon Megarad Heat Shrink Cable Joint Kit (XLPE 12/20 (24)kV)


Thorne & Derrick Specialist Electrical Distributor

Established since 1985, T&D distribute the most extensive range of LV, MV & HV Cable Jointing, Terminating, Pulling & Installation Equipment - contact us today for a competitive quotation.

Key Products : MV Joints & Terminations, Cable Cleats, Duct Seals, Cable Transits, Cable Splice Closures, Underground Cable Protection, Jointing Tools, Feeder Pillars, Cable Duct, Earthing & Lightning Protection, Electrical Safety, Cable Glands, Arc Flash Clothing Protection & Fusegear.

Distributors for : 3M, Pfisterer, Nexans Euromold, Elastimold, Catu, Roxtec, Emtelle, Centriforce, Lucy Zodion, Alroc, Hivotec, Cembre, Prysmian, Ellis Patents, ABB & Furse.

Cable Joints Terminations Tools Cleats



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Inflatable Seals For LV HV Cable Ducts, Conduits & Substation Entries

Category:  Cable Transits & Duct Sealing

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