12
C6.2.38/0719/E
Mounting parts YBVH021, YBVH029, YBVH046
– Soft mountings
Figure 11: Rubber mounting part with sleeve
3.3 Compressor brazing procedure
WARNING
Air/flammable refrigerant mixture! Creation of a potentially flammable
atmosphere! Fire hazard!
Remove all refrigerant before opening the system.
When working on a refrigerant-filled system, make sure to follow the safety
and working instructions given in
Chapter 6 "Maintenance & repair
Error! R
eference source not found.
"
.
WARNING
High temperature! Burning!
Proceed with caution when brazing system
components. Do not touch the compressor until it has cooled down. Ensure
that other materials in the area of the compressor do not touch it.
IMPORTANT
Blockage! Compressor breakdown!
Maintain a flow of oxygen-free nitrogen
through the system at very low-pressure during brazing. Nitrogen displaces
the air and prevents the formation of copper oxides in the system. If allowed
to form, the copper oxide material can later be swept through the system and
block screens such as those protecting capillary tubes, thermal expansion
valves, and accumulator oil return holes.
Contamination or moisture!
Bearing failure!
Do not remove the plugs until
the compressor is set into the unit. This minimises any entry of contaminants
and moisture.
Copeland scroll compressors have copper-plated steel suction,
injection and discharge tubes. These tubes are far more robust
and less prone to leaks than copper tubes. Due to the different
thermal properties of steel and copper, brazing procedures may
have to be changed from those commonly used.
Refer to
Figure 12
and procedure below for the brazing of the
suction, discharge and injection lines to a Scroll compressor.
▪
For systems with A3 flammable refrigerants, it is mandatory to flush oxygen-free nitrogen trough
the piping during brazing process.
▪
The copper-coated steel tubes on scroll compressors can be brazed in approximately the same
manner as any copper tube.
▪
Recommended brazing materials: any silfos material is recommended, preferably with a minimum
of 5% silver. However, 0% silver is acceptable.
▪
Be sure tube fitting inner diameter and tube outer diameter are clean prior to assembly.
▪
Using a double-tipped torch, apply heat in area 1.
▪
As the tube approaches brazing temperature, move the torch flame to area 2.
▪
Heat area 2 until braze temperature is attained, moving the torch up and down and rotating around
the tube as necessary to heat the tube evenly. Add braze material to the joint while moving the
torch around the joint to flow braze material around the circumference.
▪
After the braze material flows around the joint, move the torch to heat area 3. This will draw the
braze material down into the joint. The time spent heating area 3 should be minimal.
▪
As with any brazed joint, overheating may be detrimental to the final result.
Figure 12: Suction tube connecting
areas