|
|
|
| |
Field of application
Heat exchangers for industrial cold-storage plants and commercial air conditioners,
cryogenic units, heat exchangers for petrochemical industry and heat power
plants, vapor condensers for two-phase immersion electronic cooling and other.
Major advantages
- Significant increase of heattransfer effectiveness compared to traditional
knurling (the largest effect - at boiling and condensation processe)
- Decreasing of metal quantity and size of heat exchangers up to 1.3…3
times
- Easy to control geometry of finnig
- The ability to fin thin-wall tubes
- The ability to get tube heat exchanger surfaces in the form of pin fins
- High effectiveness, no waste of material, simple tool
- Ecologically clean, no lubricated fluid
- The ability to use standard lathes as well as special machine with extra
high productivity
| Major technical characteristics |
| |
| |
| Parameter |
Value |
| Diameter of tube billet,
mm |
6 - 30 |
| Tube length, m |
up 6 |
| Initial tube wall thickness,
mm |
from 1,0 |
| Tube material |
Copper, Brass, Cu-Ni alloys,
Aluminum,
Titanium, Low carbon and Stainless steels |
| Minimum residual wall thickness,
mm |
0,3 |
| Fin height, mm |
up to 4 mm (for copper),
but not more than initial wall thicknes |
| Fin pitch, mm |
0,2 - 2 |
| Interfin gap, mm |
0,01 - 1,5 |
| Surface area increasing,
times |
up to 12 (for copper) |
| |
| |
Strength test for finned tube
Seam-welded pipe. Stainless steel AISI 304. Initial tube billet:
OD=18 mm, wall thickness 1,5 mm.
Fins parameters:
- pitch 1.0 mm,
- fin height 1.2 mm,
-
interfin gap 0.45 mm,
-
residual wall thickness 0.75 mm.
Bursting pressure was 91,2 MPa (930 bar). Destruction occurred in
the weld seam on a non-finned site of the tube.
Finning increases tube strength
|
|
| |
|
|
|
|
