NEW
IM/A100-Ex - Rev 1
Attachment
: Specific Protective
Measures Taken for
ESCODISC Couplings
in case of use in explosive atmospheres.
0 Introduction
General assembly and maintenance instructions (called IM in this
attachment), are established for standard ESCODISC couplings according to the
following list:
IM/A100-2 for ESCODISC DLC couplings - IM/A100-3 for ESCODISC DMU couplings
IM/A100-4 for ESCODISC DPU couplings - IM/A100-5 for ESCODISC DMUCC couplings
In case of use in potentially explosive atmospheres
, further to the general assembly and
maintenance instructions(IM), the specific measures described in this attachment
must be taken.
1 Coupling
Selection
The coupling must be selected according to the general
assembly and maintenance instructions IM .
In explosive atmosphere , the following specific rules
must apply:
A Service Factor of 1.5 must be applied on the max
torque values for nominal torque (Tn) and peak torque (Tp) given in the charts
in catalogue (see Selection chart A104 and A105).
2 Use of the
coupling
The
coupling is dedicated for use in potentially explosive atmospheres according to
European Directive 94/9/EC (Atex 100 A).
Coupling
is classified in equipment group II, equipment category 2 and 3, intended for
use in areas in which explosive atmospheres caused by gases, vapors, mists of
air/dust mixtures are likely to occur.
In
function of the ambient temperature in the coupling proximity (85, 55, 45°C),
the temperature classes have been defined (T4, T5, T6).
This
is based on a temperature increase of the machine shafts (in regard of the
ambient temperature) that will not exceed 50°C in operation.
The
coupling is marked as follows:
CE II 2 G T4/T5/T6 D 120°C
-20°C Ta 85°C / 55°C / 45°C
3. Warnings
The warnings mentioned in the general assembly and maintenance
instructions IM must apply in any case.
In explosive atmosphere , the following specific warnings must apply:
· In case of supply by ESCO Couplings of couplings with a rough bore or a solid bore, the sole allowed operation that may be performed by the customer is the boring and keywaying of the coupling hubs. When machining the bore and the keyway, the following instructions must be followed:
o This job must be performed by an authorised and adequately trained and informed operator.
o The bore and keyway tolerances must be selected to insure the proper fit between shaft and bore. In case of loose fit, a set screw must be foreseen to locate the hub axially.
o The max bore may not exceed the value stated in the catalogue. The tabulated values in the catalogue are based on key dimensions according to ISO R 773.
o The reference used to centre the piece when boring, is the one referenced D in the figures of the catalogue.
· Before proceeding with any assembly, operation or maintenance operation
on the coupling, make sure that the necessary measures have been taken to
ensure safety, such as but not limited to:
o Proper ventilation of the area o Proper lightening and electrical tools.
· If hub must be heated for
assembly on the shaft, make sure heating source and surface temperature will
not affect the safety of the working area.
· It is recommended to have a
strong coupling guard, preferably in stainless steel with openings (if any) smaller
than the smallest centrifugable part (nut is 10 mm dia). The coupling guard is
intended to protect the environment from the centrifugation of any rotating
part and the rotating coupling from any falling part. To limit ventilation
effects, distance between cover and coupling outside surface should be at least
10 mm.
4. Assembly
The general assembly and maintenance instructions IM must apply in any
case.
In explosive atmosphere , the following specific instructions must
apply:
Alignment of the machine in cold condition must take into account the
possible heat expansion to make sure that in continuous running conditions, max
misalignment calculated on the base of selection chart A104 will not exceed 80%
of the max allowed value: Da/Dka +
a/Dkw + dr/Dkr 0.80
5. Operation
The general assembly and maintenance instructions IM must apply in any
case.
In explosive atmosphere , the following specific instructions must
apply:
· Before Start-up
o Make sure coupling is
perfectly clean and properly aligned. o Make sure, screws, nuts are properly tightened.
o Coupling guard must
be properly installed and fixed. o Monitoring system, if any, must be tested to verify
its effectiveness.
· During start up
o Check for any
abnormal noise and/or vibration. If any, immediate stop is mandatory and
appropriate action must be taken.
· Checking intervals during
operation
o After
the first 3000 hours or 6 months:
§ Inspect external disc for
any fatigue crack. § Verify
alignment
· Continuous checking
o Immediately
stop the machine if noise, vibrations or other abnormal phenomena are detected
during operation.
o Further
more, if direct check is not possible for access or safety reasons, proper
monitoring system has to be installed to follow up couplings behaviour
6. Maintenance
The general assembly and maintenance instructions IM must apply in any
case.
In explosive atmosphere
, the following
specific instructions must apply:
· Every 8.000 hours or 18
month:
o Dismount
the coupling and inspect.
o Proceed
as indicated in point 4