Page 46 - Industrial Plants 2014

• physical size: LED sources are smaller than all form of gas, fumes or mist, during routine activities”
other light sources. This is important because it were considered in this study.
allows designers freedom of choice to design In regard to the technical illumination aspects, the
lighting systems that perform their task in the best Norsok Standards were also taken into account, since
possible way; the system in question was constructed in accordance
• switching on the power and circuits used to with said standards. Table 1 shows the average
switch it on: LEDs do not require any particular illuminance values for the drilling infrastructure sections
auxiliary circuit to be switched on, which is covered by the study [5].
instantaneous, as opposed to discharge lamps The average illuminance level of the various sections
which typically also need a certain amount of time was measured at a height of 1 m above the floor and
to reach the minimum operating conditions. This was found to be suitable for the task or process that
aspect must be considered in relation to the use takes place in the area concerned, in such a way as to
made of a lighting system. ensure an appropriate level of lighting. In order to
maintain a certain brightness uniformity within each
section, the ratio between the average illuminance and
1. Standard the minimum illuminance must be at least equal to:
It is important to define the applicable standards before • 0.5 in the utility, process and drilling areas;
proceeding with an energy assessment. Since this • 0.7 in individual work areas.
application is a hazardous environment for the formation
of explosive atmospheres caused by gas leaks or oil
fumes, it is necessary to follow Atex directive 94/9/EC 2. Case studies
and the related IEC/EN standards for the classification The comparison in terms of installed power is carried
of areas [4]. Therefore, explosion-proof lighting devices out with a lighting system based on the use of standard
Table 1 - Average classified for Zone 1. for “places where, occasionally, luminaires and a lighting system based on the use of
level of illuminance at there is likely to be an explosive atmosphere composed semiconductor light devices (power LED) in relation to
a height of 1 m of a mixture of air and flammable substances in the the equal illuminance required by the standard. To do
this it is in any case necessary to know the precise

Description of the location Average level of shape and size of the system to be illuminated and the
illuminance (lux) types of lamps and devices to be used.

Walkways and external access routes 100
2.1. Oil plant
Stairs, walkways and access routes in internal working areas 150
The study was carried out on an offshore oil plant.
General process and utility areas 200 Generally, a drilling installation (figure 3) is composed

Laboratory 500 of [6] [7]:
• derrick;
Drilling cabin 400 adjustable • drill floor;
• BOP (Blow Out Preventer) deck;
Drill foor 350
• mud module.
Derrickman (*) platform (monkey board) 200
A derrick is a lattice metal structure, with a square
Area rack for drill 200
base, tapering upwards, which stands on the drilling
Laboratories for measurements and well and drilling fuid data records 500 floor of a rig. A derrick has vertical drill pipes attached
that are screwed in or unscrewed when lowering or
Vibrating sieve for the separation of drilling debris (shale shaker) 300
recovering the drills. There are also one or two small
Drilling mud area, mixing area 200 floors, depending on the height, at different levels, from
which workers can move the drill pipes. A derrick is
Drilling mud area, control units (test stations) 300
typically 45 m high.
Drilling mud laboratory 300 The drilling floor is a working level of the drilling system,
located at the base of the tower and raised above the
Operator’s cabin in the drilling unit 400
main deck of an oil installation, from which the well
Blowouts prevention system area (BOP) and wellhead 150 drilling activities are carried out. This area is composed
as follows:
(*) Derrickman: an operator positioned on a bridge on a derrick, who has the task of • rotary table, which guides and transmits the
guiding the length of the drillpipes during drilling activities of safety and time, and movement power to the drill string;
which is then placed in a vertical position using the plant’s winch • drilling cabin;

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