8
ITEM
A-03-343
DATED
NOVEMBER 2012
SUPERCEDES
MARCH 2011
LONG-TERM SHUTDOWN.
MAINTENANCE AND REPAIR:
PREPARATORY PRECAUTIONS. Before operations are
started, check the delivered frame type of the plate heat
exchanger on the basis of the documentation supplied.
Danger of injury!
During maintenance and
repair work on the heat
exchanger there is risk of
injury. For this reason,
always adhere to the
following points:
1. Always wear suitable
protective clothing.
2. Remember to release the
pressure and drain the heat exchanger before opening it. If
a pressurized or filled heat exchanger is opened, the flow
media can escape uncontrollably. This is a danger of injury
for the operator and bystanders.
3. When using hot or very cold flow media there is a danger of
burning or freezing. Before beginning maintenance or repair
work, always ensure that the heat exchanger has reached
room temperature.
4. Hazardous flow media (corrosive, poisonous, flammable,
explosive etc.) present an acute danger of injury for the
operator and bystanders. Make sure that the regulations for
flow media are followed during all work.
5. Ensure that the loose pressure plate is secured against
unintended slippage.
6. The plates of the heat exchanger with a CY frame can
fall out sideways and cause severe injuries. When fitting
the plates of the heat exchanger and closing the heat
exchanger, always ensure that the heat exchanger plates do
not unexpectedly loosen from the guide bar and tip over.
For this reason, at least two persons should work on a
heat exchanger with CY frame. The reliable procedure for
opening and closing a heat exchanger is described in the
sections “Opening the Plate Heat Exchanger and Removing
The Plates” or “Reinstalling the Plates and Closing the Plate
Heat Exchanger”.
NOTE: When removing the heat exchanger plates, document
the order with the help of the flow diagram.
The frames are provided with at least four tie rod assemblies.
For heat exchangers with more than four tie rod assemblies,
four of the tie rods are longer than the rest. These only
pretension the heat exchanger plate pack (so-called
pretensioning bolts).
The heat transfer plates are
mounted in different ways
in the frame, depending
on the frame design of the
plate heat exchanger.
1. In CY frames the heat
exchanger plates rest on
the bottom beam and are guided by the top beam.
2. In the BY frames the heat exchanger plates hang from the
top beam. The plates hook onto the rail of the upper beam
and are guided by the bottom beam.
OPENING THE HEAT EXCHANGER AND REMOVING
THE PLATES.
NOTE: Before unfastening/opening the heat exchanger, observe
the safety instructions in the section “Preparatory Precautions”.
OPENING PLATE HEAT EXCHANGERS WITH A CY
FRAME. The drawings below show a CY frame with a full-
height support leg (CYFL). These instructions also apply to
CY frames with support legs that support only the lower beam
(CYFS).
Danger:
Premature Component Wear
The components of the heat exchanger can prematurely
wear due to unfavorable ambient conditions or by flow
media remaining within the heat exchanger.
1. If the heat exchanger is decommissioned for a longer
period, it should be decompressed and completely
emptied.
2. Additionally we recommend a thorough cleaning and
appropriate storage until recommissioning.
CAUTION
Danger:
Danger of Falling Over
During Stacking
In the case of uncontrolled
stacking, the heat exchanger
plates can tumble. This causes
injuries and damaged heat
exchanger plates. Never stack
the plates higher than 60 heat
exchanger plates.
Before opening the plate heat
exchanger you should carry out
a few work steps. If necessary,
remove the connected pipes.
Carry out the following work
steps:
1. Clean the upper beam (for
better plate mobility).
2. Clean the threads of the
tightening bolts (to remove
contamination and prevent
binding of the nuts).
3. Apply a thin film of oil to the threads of the tie rod.
4. To ensure that the plates are reassembled in the right
order, we advise painting a diagonal line across the
side of the plate pack. Be sure to note the current “a”
dimension.
