CASE STUDIES – ELECTRICAL

Case Study – Power distribution – Hillingdon

Case Study – Power distribution – Bracknell

Fibre1

CASE STUDY 1

Power distribution – Hillingdon

OCU EHV Services were contracted by SSE to install & joint two circuits
of 132kV cables from Iver to Hillingdon and 3 132kV circuits for Iver to
Uxbridge with associated bre-optic pilot cables and chambers. SSE
took the opportunity to install 11kv ducts for two local projects where
there was a common route, to avoid having to re-excavate trenches
for planned schemes in the near future.

The Project was designed to provide system that would achieve a
continuous winter rating of 108MVA with circuits loaded. The cables
were inserted into pre-installed trefoil ducts to minimise trade
disruption and avoid cable sheath damage.

There were a number of Special Engineering Difficulties (SED’s) to
overcome to construct the Project that included horizontal directional
drills (HDD’s) at ve locations. Ducts were drilled beneath the River
Colne and asbestos contaminated land from Iver Grid in six separate
bores. Beneath the Grand Union Canal three bores at one location
and a further two bores at a separate location. The River Fray and
River Pinn were each was negotiated with two HDD bores to provide
a route for the two Iver – Hillingdon circuits.

OCU installed approximately 44,000m of 1200mm² Cu 132kV power
cables in 5.20km of trench on the Project. The works included trenching
in residential areas, Parks, Trunk Roads/A Class Roads.

The Project also included the design and construction of sealing end
structures and terminations at Uxbridge and Hillingdon Substations.

The works were programmed to take into consideration the Local Authorities requirement for works outside Schools to be completed during School Holiday close-down periods and involved weekend and out of hours working arrangements to help minimise disruption to residents and local trade.

OCU EHV Project Services were responsible for System Design, installation and the Jointing of 81 132kV straight joints and 15 terminations was completed by OCU’s own highly trained and skilled Jointers who are approved to joint cables up to 275kV.

Term of Contract:
July 2011 – January 2013
Location: Between Bracknell & Camberley Substations
Value: £15,000,000.00 approximately.
Services:
System Design
Project Management
Site Engineer
132kV Cable installation
33kV Cable installation
Fibre-optic Cable installation
HDD Services
Joint Bay Construction
132kV & 33kV Cable Jointing
Fibre-optic Cable Splicing
Fibre-optic Pit Construction
All 132kV, 33kV & Fibre-optic Cable Testing
CAD Drawing of As-laid routes

 

CASE STUDY 2

Power distribution – Bracknell

OCU EHV Services were contracted by SSE to install & joint
two circuits of
132kV cables with associated bre-optic
pilot cables. SSE took the
opportunity to install 33kv cables
for local projects where there was a
common route to avoid
having to re-excavate trenches for future schemes
in the
near future.

The Project was designed to provide system that would
achieve a
continuous winter rating of 195MVA with both
circuits loaded.

The cables were inserted into pre-installed trefoil ducts to
minimise trade
disruption and avoid cable sheath damage.
There were a number of
Special Engineering Diculties
(SED’s) to overcome to construct the
Project that included
ve horizontal directional drills (HDD’s) beneath
the Twin
Bridges roundabout, waterways, railway lines, A331 Culvert
etc.

OCU installed approximately 69,600m of 1200mm² Al &
9,600m of
1,000mm² Cu 132kV power cables in 12.1km of
trench on the Project.
The works included trenching 5.2km
of the route on MOD property
through Married Quarters
and Firing Ranges etc.

The works were programmed to take into consideration the
Local
Authorities requirement for works outside Schools to
be completed
during School Holiday close-down periods
and involved weekend
and out of hours working
arrangements to help minimise disruption
to residents and
local trade.

OCU EHV Project Services were responsible for System
Design,
installation and all Jointing was completed by
OCU’s own highly
trained and skilled Jointers who are
approved to joint cables up to 275kV.

Testing is programmed to be completed in January 2013.

Term of Contract:
July 2011 – January 2013
Location: Between Bracknell & Camberley Substations
Value: £15,000,000.00 approximately.
Services:
System Design
Project Management
Site Engineer
132kV Cable installation
33kV Cable installation
Fibre-optic Cable installation
HDD Services
Joint Bay Construction
132kV & 33kV Cable Jointing
Fibre-optic Cable Splicing
Fibre-optic Pit Construction
All 132kV, 33kV & Fibre-optic Cable Testing
CAD Drawing of As-laid routes