Method
Before winding, the fin strip material is formed by rollers
to "crimp" the fin.
The strip is then helically wound under tension onto the surface
of the tube. Due to the "wave" form on the edge
of the formed strip, the resulting effective increase in contact
length ensures a good mechanical (and therfore thermal) contact
between fin and tube.
Both ends of the spiral fin are either welded or brazed to
the tube to prevent any possibility of unwinding.
Uses
For many years, the Crimped Fin Tube has proven to be the
most effective and economical element used for space heating
due to the large surface area per linear foot obtained in
the crimping process.
Sizes
The sizes shown in the table below are the most common pipes
found in Space Heating Systems.
|
Pipe
Size IPS
|
Fin
Size
|
Diameter
Over Fins
|
Fin
Spacing
|
Surface
Area
FT2/lin. FT.
|
External
Surface
/ Internal Surface
|
Approx.
Weight
Per Ft. (Lb)
|
|
3/4"
|
.065
x 3/4"
|
2-1/2"
|
7/16"
3/8"
|
2.51
2.85
|
11.7
13.3
|
2.7
2.85
|
|
1"
|
.065
x 3/4"
|
2-13/16"
|
7/16"
3/8"
|
2.80
3.20
|
10.2
11.6
|
3.25
3.5
|
|
1
1/4"
|
.065
x 3/4"
.036
x1"
|
3-1/8"
3-5/8"
|
7/16"
3/8"
5/16"
1/4"
|
3.25
3.72
4.18
7.96
|
9.0
10.3
11.6
22.0
|
4.5
4.8
5.1
5.8
|
|
1 1/2"
|
.065
x 3/4"
.036
x 1"
|
3-3/8"
3-7/8"
|
7/16"
3/8"
5/16"
1/4"
|
3.50
4.00
4.50
8.54
|
8.3
9.5
10.7
20.2
|
5.0
5.3
5.6
6.7
|
|
2"
|
.065
x 3/4"
.036
x1"
|
3-7/8"
4-3/8"
|
7/16"
3/8"
5/16"
1/4"
|
4.13
4.71
5.30
9.69
|
7.6
8.7
9.8
17.9
|
6.6
7.0
7.4
8.2
|
|
2 1/2"
|
.065
x 3/4"
.036
x 1"
|
4-3/8"
4-7/8"
|
7/16"
3/8"
5/16"
1/4"
|
4.65
5.31
5.98
11.02
|
7.2
8.2
9.3
17.1
|
|
|
3"
|
.065
x 3/4"
|
5"
|
7/16"
3/8"
5/16"
|
5.36
6.11
6.88
|
6.7
7.6
8.6
|
11.4
11.9
12.5
|
