EoW January 2012

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EuroWire – January 2012 40
News
Technology
A cable and hose management solution was needed for an
automated drill rod handler on a Bauer deep drilling rig, and
other than performance and ATEX-conformity, longevity and
service life were of importance.
A Kabelschlepp hybrid energy drag chain now provides the
answer. Everyone has experienced static energy at some point
and these electrostatic discharges are not only hazardous to
people due to the shock reaction, but they can ignite flammable
materials.
This also applies to machinery, tools and equipment in industrial
applications such as in civil engineering and mining, refining
or chemical processing. Movement and friction create a static
charge, and the inevitable discharge can have devastating
consequences in oil or gas production. Bauer Maschinen GmbH
knows this is only too well. In product development of deep
drilling devices, there are strict requirements for explosion
prevention.
A vertically fitted MC 1300 type Kabelschlepp drag chain
manages the required electric and hydraulic feeds on the mast
of deep drilling rig TBA 300. The previous solution of grouping
hose and cable in festoon bags needed replacement to fast
movements in operation, and the variety of lines to be handled.
The MC 1300 chain was chosen as the inner height of 87mm and
the bespoke compartment width of 650mm.
The multi-variable chain is designed for tough conditions on
construction sites, a rigid link design makes it extremely robust,
and it is equipped with an enclosed and dirt-resistant stop
system.
This stability achieved by the combination of GRP side band and
aluminium cross stays also offers good conductivity to avoid
excessive static charge.
The ATEX Directive stipulates that all components must have
controlled discharge properties. To follow the directive, and
essential for ATEX applications, the chain band is made of a
special, conductive material.
The special material for this design delivers the required
properties while retaining the abrasion resistance and stability.
This is particularly important for the TBA 300: it is not only
more cable to handle, but also larger diameters. The result is
higher loads on the chain and the separators.
Apart from increased torsional stiffness and conductivity, the
properties of the aluminium cross stays reduce friction. Even
if cables do have appropriate sheathing and modern plastics
are less abrasive, aluminium by far copes better with heavy
cable. In addition, Kabelschlepp’s diverse offering of stay and
shelving systems covers includes hole stays (LG type).
Enclosing cable and hose they feature identical advantages in
terms of conductivity and stability as other cross stay designs.
In a vertical application they have the additional advantage of
controlling the momentum. The hole stay pattern is designed
to suit the OD of cable and hose, and friction or twisting is
impossible.
Holding the media in the centreline of the radius, length
variances hence movement and wear is avoided. Hanging
cable and hose tends to elongate and needs readjusting from
time to time. Bespoke strain relief on both ends with cable
and hose clamps secure cable and hose. Compared to loose
lines, invariably subject to reduced service life and chafing due
to the relative movements, the service life is extended to a
maximum, and cost is prevented.
Kabelschlepp – Germany
Fax: +49 276 2400 3220
Email:
Website:
Sparks out of bounds
▲ ▲ Kabelschlepp cable carrier MC1300 with EX rated GRP chain bands and
aluminium hole stays