Sealing Cables | 400kV Substation Cable Sealing using CSD Systems

Published 24 Oct 2023

NOFIRNO | Sealing Substation Cables | 400kV High Voltage (HV)

Water & Gastight Cable Sealing

CSD Sealing Systems were recently contracted to carry out water and gastight sealing of cable ducts on a newbuild High Voltage substation project where the previously installed seals were leaking.

The NOFIRNO® Duct Seal System was used to successfully seal all entry points so that all buildings were water and gastight, helping to prevent water ingress, reduce the risk of equipment damage and ensure the site remains operational.

CSD Technical Services were contracted to carry out water and gastight sealing of cable entry points on this new build substation project. This substation would prove to be one of the largest built substations built across the UK and would ensure the transmission of renewable energy generated from a new offshore windfarm.

The NOFIRNO Duct Seal is designed to provide simple and effective long term building entry sealing protection. The system can be used in new build projects or in retrofit applications to replace existing failing seals. It can be installed directly in to concrete openings, plastic ducting or into any existing transit frames.

Sealing Substation Cables

The previously installed seals were leaking and therefore the client was concerned regarding the damages these leaks could bring to their assets. The NOFIRNO Duct Seal system, manufactured by CSD Sealing Systems and distributed in the UK by Thorne & Derrick, was the preferred solution to prevent flood damage to the high voltage (HV) cables and electrical infrastructure.

Outcome of Using Duct Seal Systems

All previous sealing materials were carefully removed ensuring that no cables were damaged during the removal. Following removal of the failing seals our team thoroughly cleaned all cables and the duct openings to remove all old sealant and any dirt, dust, and concrete.

All entry points were successfully sealed across the site using CSD’s NOFIRNO Duct Seal system. All buildings are now water and gastight helping to prevent water ingress and reduce the risk of equipment damage and ensure the site always remains operational.

nofirno seal system

The NOFIRNO Duct Seal system comprises of two components; 60mm rubber NOFIRNO multi-sleeves which provide cable support, ensure cable separation, and provide a backing for the second component which is a 20mm layer of NOFIRNO Sealant.

To ensure the NOFIRNO Sealant adheres correctly, the areas where the sealant is to be applied should be clean and dry before application i.e., the cables and any frames/structures. The NOFIRNO multi-sleeves are then installed providing cable separation and a firm backing for the NOFIRNO Sealant layer. The system will provide a water and gastight seal to certified levels of 2.5 bar and has been shown to provide protection for a period of at least 50 years.

Key benefits of duct seal systems

• Tested to prove no deterioration in performance for more than 50 years
• Providing flood protection and preventing water and gas ingress – pressure rated up to 2.5 from the front and back of the seal
• Quick and easy to install
• Accessible re-entry for adding, removing or replacing cables

HV Substation | Cable Sealing

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