6
C6.2.27/0716-0219/E
Mounting parts ZB50K* to ZB114K* and ZF25K* to ZF54K* - Soft mountings
Figure 2: Mounting parts
3.2
Brazing procedure
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 3
and procedure below for the brazing of the
suction and discharge lines to a scroll compressor.
▪
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.
To disconnect:
▪
Heat joint areas 2 and 3 slowly and uniformly until the braze material softens and the tube can
be pulled out of the fitting.
To reconnect:
▪
Recommended brazing materials: Silfos with minimum 5% silver or silver braze used on other
compressors. Due to the different thermal properties of steel and copper, brazing procedures
may have to be changed from those commonly used.
NOTE: Since the discharge stub contains a check valve, care must be taken not to overheat
it to prevent brazing material from flowing into it.
Figure 3: Suction tube brazing areas