A new face drilling rig for narrow tunnels and ... - Advanced Mining

Having neglected the very complex sound diffusivity,
whose treatment requires the use of a specialized software,
however, it is enabled the admissible sound power of the
new coal logistics to be assessed, even with the aid of
simple means.
The sound power levels shown in the table, and
calculated on the basis of the admissible sound pressure
levels at the places of immission would only be accepted,
if the plant could be considered point sound source. But
since the individual machines and plant components are
spread over a large surface, the influence individual sound
sources have on different places of immission is highly
varying. That is why the part in the sound pressure the
slewing crane in the port has at the place of immission 1
will be far bigger than that at the place of immission 2 or
3. So, the position and distribution of the individual noise
sources need to be taken into account when fixing their
maximally admissible sound power levels. That is the
direct consequence of the closeness of residential areas
to the plant. It can be made a rule, as formulated in the VDI
2714 no longer valid today, that an accumulation of noise
sources can be considered point sound source then, if the
distance from the centre point of the noise sources will be
at least twice the diameter of the circle surrounding the
noise sources.
Structure of the plant
Let us follow the way of the coal from its
arrival at the port by means of pusher barges
to the stockyard, and its further transport to
the coking plant.
Slewing crane
The slewing crane that is located in the port
serves to unload the pusher barges. The coal
taken out of the barges by the slewing crane
gets discharged into the travelling bin attached
to the crane. The bin’s task is to feed the coal
on to the discharge belt conveyor uniformly.
Moreover, by using trucks and wheel loaders
it is possible to create slag dumps on that side
of the discharge belt conveyor turned away
from the harbour basin, and to have them
loaded by the slewing crane into the barges.
Issue 04 | 2010
Fig. 9:
Plant scheme HKM
TRANSFER OF TECHNOLOGY
As far as the noise emission is concerned, it has been
decided that the noises the pusher barges produce as well
as the noises resulting from the contact of the grab with
the hatch wall or bottom will not slip into the noise balance.
These noises, very highly dependent on the crane driver’s
experience and skill, did already exist before.
The crane construction is a proven, solid type, mainly
consisting of the portal that is arranged parallel to the quay
and travelling on rails, the machine house situated over the
central column and mounted on the portal through a ballrace
slewing connection, as well as the boom. The boom
is a latticework construction and rigidly connected to the
steel structure of the crane upper section.
The drive units belonging to the lifting-, closing and
slewing gears turned out to be the essential noise sources
of the crane. Furthermore, it could be found out that the
air conditioning systems serving to cool down the E-house
represent a further noise source not to be neglected. On
the other hand, it is enabled the sound power achieved by
the travel drive units to be neglected. A detailed analysis
of the crane through airborne noise measurements on
the whole crane and on individual units, as well as the
www.advanced-mining.com
78