6. Commissioning, operation
6.7 Tube clip welding
Attach clips at predetermined locations. Preheat area before welding if required.
■
Weld tube clip ends only and ensure there is a loose fit (no friction) between the
mineral-insulated cable and the clip (see figure 2).
The tube clip should allow axial expansion of the mineral-insulated cable.
■
Weld clips maximum every 300 mm (12") to 450 mm (18") of run.
■
Figure 2: Tube clip welding
MI cable
Fillet
weld
Fillet
weld
6.8 Expansion loops
Expansion loops should be designed to account for maximum tube movement from start up
position to operating temperature. Loops should be designed in accordance with allowable
space available. Examples of expansion loops are S-loop, multiple coil, single coil and spiral
loop.
S-loop
Single coil
WIKA operating instructions model TC59-W (WELD-PAD)
Multiple coil
Spiral loop
EN
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