Danfoss Performer SM Series, Выбор и руководство по применению

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Filter driers
For new installations with SY / SZ
compressors with polyolester oil,
Danfoss recommends using Danfoss
DML 100% molecular sieve solid core
filter driers. Molecular sieve filter driers
with loose beads must be avoided. For
servicing existing installations where
acid formation is present, Danfoss
DCL solid core filter driers containing
activated alumina are recommended.
For new installations using SM compressors with mineral oil the
Danfoss DCL drier is recommended.
The drier is should be oversized rather
than undersized. When selecting a
drier, always take into account its
water content capacity, the system
refrigeration capacity, and the system
refrigerant charge.
copper to copper brazing
When brazing copper-to-copper
connections, the use of a copper/
phosphorus brazing alloy containing
5% or more silver, with a melting
temperature below 1500°F is
recommended. No flux is required
during brazing.
Brazing dissimilar metals
When brazing dissimilar metals such
as copper and brass or steel, the use of silver solder and anti-oxidant flux is
necessary.
compressor connection
installation
Brazing and soldering
heat shield
a
B c
When brazing the fittings, do
not
overheat the compressor
shell. Overheating can severely
damage
internal components.
Using a heat shield, a heat-
absorbing compound (or both) is
recommended. Due to the relatively
large tubing and fitting diameters
used for larger scrolls, a double
tipped
acetylene torch is
recommended for S240-300-380
brazing operation.
For compressors with rotolock
connections, solder sleeves are
available. For brazing the suction and
discharge connections, the following
procedure is advised:
•
Make sure that no electrical wiring is
connected to the compressor.
•
Protect the terminal box and painted
surfaces of the compressor heat
damage (see diagram).
•
Remove the teflon gaskets when
brazing rotolock connectors with
solder sleeves.
•
Use only clean refrigeration-
grade copper tubing and clean all
connections.
•
Use brazing material with a minimum
of 5% silver content.
•
Purge nitrogen or CO
2
through
the compressor in order to prevent
oxidation and flammable conditions.
The compressor should not be exposed
to open air for extended periods.
•
Use of a double-tipped torch is
recommended.
•
Apply heat evenly to area A until
brazing temperature is reached. Move
the torch to area B and apply heat
evenly until brazing temperature has
been reached there as well, and then
begin adding the brazing material.
Move the torch evenly around the
joint, applying only enough brazing
material to flow the full circumference
of the joint.
•
Move the torch to area C only long
enough to draw the brazing material
into the joint, but not into the