Roxtec has developed a reputation for sealing

cables and pipes entering structures and its

products are now increasingly being used to

protect equipment. There are multiple hazards

to consider with cable entries including light-

ning, gas, fire, dust, flood, humidity, rodents,

electro-magnetic disturbances and the risk of

explosion. However, traditional sealing sys-

tems only tend to protect against one particu-

lar hazard. The effective protection of electrical

equipment in manufacturing, power, industrial

and hazardous environments has become

a major engineering challenge. In addition,

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Cable & wire

Sealing cables over land and sea

Roxtec has specialised in the delivery of sealing solutions for panel building and

system integration for more than two decades with the firm’s seals being used within the most demanding environments on land and at sea all over the globe.

The effective protection of electrical equipment in manufacturing, power, industrial and hazardous

environments has become a major engineering challenge.

industry is calling out for cable transit devices

which can significantly reduce the quantity,

size and weight of cable sealing systems.

Withstanding high water pressure and preventing ingressA recent project within the wastewater sector

saw Roxtec involved in a £220m water

treatment upgrade project in London. This

involved the supply of multi-cable transit seals

to Thames Water for its Crossness Sewage

Treatment Works - the second largest in Eu-

rope. Roxtec’s seals were used throughout the

site to help protect one of Greater London’s

last remaining grazing marsh lands. The major

project enabled the site east of the capital to

treat 44pc more sewage than its previous ca-

pacity. The upgrade also significantly reduced

the amount of storm sewage that overflows

into the River Thames when the site becomes

overloaded due to rainfall. Renewable energy

sources on site include a wind turbine and

thermal hydrolysis plant (THP).

The THP works as an industrial-scale

‘pressure cooker’ to heat sludge, the leftover

solids from wastewater treatment, to around

160 °C. It produces up to 50pc more biogas

which is then burnt to create heat to gener-

ate renewable energy. Roxtec’s seals were

selected because of their durability and

flexibility - they can withstand extremely high

water pressure and prevent water ingress

which is vital in a project of this nature. They

are used specifically to seal power and control

cables in the water works, the THP and the

wind turbine. The gas tight seals also help to

protect local wildlife by preventing sewage

from entering the River Thames while guarding

against fumes. The IP67 rated seals further aid

Thames Water in protecting its assets against

other hazards such as fire and vermin.

Effective sealing for multiple cables and pipes When building the Project Q Data Centre in

Queretaro, Mexico, the owner representative

Santander Global Facilities México faced

a real challenge sealing cable and pipe

penetrations. The project required multiple

cables and pipes to be routed through a

45-centimetre thick wall while maintaining

integrity. Construction coordinator DIINESA

specified Roxtec cable entry solutions. Due

to the sensitive equipment within the data

centre, the construction project required all

perimeter walls to be completely watertight

and weather resistant. The walls were also

to be fire resistant and capable of keeping

out rodents and insects. It was obvious that

the traditional cable sealing method, which

consisted of a portion of pipe cast into the

wall with intumescent mastics, would not

work. However, Roxtec’s seals are area

efficient and easy to adapt to cables and

pipes of different sizes.

The installers from Lebanc handled cables

ranging from 13mm to 34mm in diameter

and pipes from 29mm to 305mm. The seals

can be opened to provide spare capacity.

Due to the high safety demands, special

concrete mixtures and last generation water-

proofing were used to ensure the wall surface

was impermeable. Naturally, the cable and

pipe transits had to meet the same strict

requirements. However, the huge perimeter

wall was made of high strength concrete

making it difficult to open a passage for ad-

ditional installations in the future. That is why

the goal was to leave transit preparations for

easy upgrades. It was crucial to find a way

of holding together many pairs of sleeves

with a sealing system at a distance of 45cm.

DIINESA and Roxtec managed to solve the

problem – with custom made steel structures

that were cast between the sophisticated

grillage foundation allowing only small toler-

ances between walls. The steel structures

hold together seals and frames through a

pair of sleeves connected with paper casting

moulds.

Quick and easy cable replacement When designing the spreaders, extruders

and ovens for the global baking industry,

Haas-Meincke A/S was keen to incorporate

a cable sealing solution which could keep

dust out and prevent water from entering

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Due to the sensitive equipment within the data centre, the construction project required all perimeter

walls to be completely watertight and weather resistant.

and damaging equipment during high pres-

sure hosing. Haas-Meincke A/S developed

the machines to ensure high reliability in

production and a high level of hygiene. How-

ever, its former cable sealing solution, using

cable glands, often gave rise to problems

due to the accumulation of debris. Roxtec

seals now ensure that cable failures are less

frequent, which helps avoid unnecessary

machine downtime. If a cable should fail,

replacement is quick and easy even if the

cables are of different sizes and pre-termi-

nated at both ends. Haas-Meincke A/S now

consciously designs its products to incorpo-

rate Roxtec seals right from the start. A key

advantage is that Roxtec can offer a 100pc

integrated solution for those machines with

stringent requirements for water-tightness

and ease of cleaning.

Customised bulk-head and deck seals Another area Roxtec is driving innovation

is the offshore windfarm sector. Roxtec

was recently involved in a project in the

North Sea. The firm delivered cable transit

systems - which are a key safety compo-

nent to safeguard workers, structures and

equipment. The systems are located on

a substation platform created as part of

the Dudgeon Offshore Windfarm, sitting

20 miles offshore near the seaside town

of Cromer in North Norfolk. It involved the

delivery of customised bulkhead and deck

seals designed to be flexible with easy

maintenance access and spare capacity

for upgrades. They are both easy to install

and inspect. The cable sealing systems

are further designed to meet the long-term

lifecycle of the 402MW wind farm whose

turbines will provide power to 410,000

UK homes and is set to be commissioned

during 2017.

Roxtec delivered A0/A60 bespoke seals for

HV and MV applications on the substation

platform. They also seal array cables to MV

switchgear and cables from MV switchgear

to transformer input. Additional products

have been used on the platform’s cables

linking its transformer to its Gas Insulated

Switchgear (GIS) and on export-to-shore

cables. Roxtec has now been involved in

cable sealing projects across more than 40

offshore wind farms in Europe. Seals are

used for different applications in windfarm

projects, from control cabinets to genera-

tors and converters. They offer protection

against fire, gas, water pressure and corro-

sion and provide cable retention.

Passing on knowledgeDue to the knowledge acquired over many

years, Roxtec has devised a programme of

accredited technical CPD seminars covering

the importance of sealing cables and pipes

in a variety of industries. These are based

upon industry standards and Roxtec’s own

practical experience.

Clive Sharp, UK Managing Director at

Roxtec

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Seals are used for different applications in windfarm projects, from control cabinets to generators

and converters.