Control And Operation - Alfa Laval 34500021401 Manual De Instrucciones

Connections (Figure 3)
Threaded connections – Use a torque wrench when
connecting the pipe and observe the specified limits.
Some models are supplied with connections type
Victaulic.
Brazed connections – Clean by rubbing down and
degreasing the various surfaces. Use a brazing metal
grade that is suitable for the materials being brazed,
and use the correct brazing temperature. For detailed
information refer to the document "Brazing tubes for
brazed heat exchanger" or contact an Alfa Laval
representative.
Welded connections – TIG or MIG welding. Grind
inside and outside of the pipe and, if bevelled, also the
bevelled edge at least 25 mm from the pipe edge and
inward. This should be done to avoid contamination of
copper in the welded area, which might cause the weld
to crack.
Note: Protect the heat exchanger against overheating by
wrapping a piece of wet cloth around the connection whenever
any brazing or welding is being done. Excessive heating could
melt the internal brazing metal inside the heat exchanger.
Refer to figure 3.
Caution: When disconnecting the heat exchanger from
the piping system use proper protective equipment,
such as safety boots, safety gloves and eye protection,
depending on the type of media in the heat exchanger.
Risk of freezing
Caution: Bear in mind the risk of freezing at low
temperatures to avoid damage to the Heat exchanger.
Heat exchangers that are not in operation should be
emptied and blown dry whenever there is a risk of
freezing.
Note: To avoid damage due to freezing, the medium used
must include an anti-freeze agent at operating conditions
below its freezing point.
Note: When used as an evaporator
• Use a flow switch and a low-pressure switch.
• Use an anti-freeze thermostat and flow monitor to ensure a
constant water flow before, during and after the compressor
has been running.
• Avoid "pump-down", i.e. emptying the evaporator by running
the compressor after shutdown until a preset refrigerant
pressure is reached. The temperature could then drop below
the brine freezing point, which could damage the evaporator.
Protection against clogging
Use a filter as protection against the possible
occurrence of foreign particles. If you have any doubt
concerning the maximum particle size, consult your
nearest representative of the supplier or look under
Product information on the supplier's Internet site.

Control and operation

Caution: Do not use the heat exchanger for media
(e.g. de-ionized water)/installations (e.g. galvanized
pipes) that (chemically/electrochemically) could affect
or be affected by the plates (Stainless steel) and the
brazing material (Copper).
Note: Copper may generate corrosion in installation with
mixed materials
Part number 340500021401
Alfa Laval Brazed Heat Exchangers
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