1. Principle of T-shaped finned tube:
T-shaped finned tube is a kind of high efficient heat exchange tube, which is formed by rolling the plain tube. The structure of T-shaped finned tube is characterized by forming a series of spiral annular T-shaped tunnels on the outer surface of the tube. When the medium outside the tube is heated, a series of bubble nuclei are formed in the tunnel. As the tunnel cavity is heated around, the bubble nucleus expands rapidly and fills the inner cavity. Continuous heating increases the pressure inside the bubble rapidly, prompting the bubble to eject rapidly from the slit on the tube surface. When bubbles are ejected, they have a large scouring force site and generate a certain local negative pressure, which makes the surrounding liquid with lower temperature flow into the T-shaped tunnel and form continuous boiling. In unit time, the heat taken away by unit surface area r} is much greater than that of bare tube, so this tube type has a higher boiling heat transfer capacity.
2. Characteristics of T-shaped finned tube:
T-shaped finned tube has good heat transfer effect. The boiling heat transfer coefficient of T tube in R113 medium is 1.6 times to 3.3 times higher than that of smooth tube. For conventional bare tube heat exchanger, only when the temperature of the hot medium is higher than the boiling point or bubble point of the cold medium by 12 ℃ - 15 ℃, the cold medium will bubble and boil. The T-type finned tube heat exchanger only needs a temperature difference of 2 ℃ - 4 ℃, and the cold medium can boil, and the bubble is fine, continuous and fast, forming a unique advantage compared with the smooth tube.
The single tube experiment with Freon 11 as the medium shows that the boiling heat transfer coefficient of T-tube can reach 10 times of that of bare tube, and the total heat transfer coefficient of small tube bundle experiment with liquid ammonia as the medium is 2.2 times of that of bare tube; The industrial calibration of reboiler of C3 and C4 hydrocarbon separation tower shows that the total heat transfer coefficient of T-tube is 50% higher than that of smooth tube at low load and 99% higher at high load.
T-shaped finned tube is cheaper than aluminum porous surface heat transfer tube.
As the gas-liquid disturbance inside the T-shaped finned tube tunnel is very intense and the gas is ejected at a high speed along the T-shaped slot, scaling is not easy to form inside the T-shaped slot or on the outer surface of the tube, which ensures that the equipment can be used for a long time without the heat transfer effect being affected by scaling.
3. Specification of T-shaped finned tube:
16 FINS / INCH FIN PITCH M = 1.59mm
|
Plain section
|
|
|
Finned section
|
|
|
|
Code No.
|
External
Ø
|
Int.
|
Wallthickn.
|
Root dia.
Ø
|
Ext.
Ø
|
Wall-thickn.
|
Ext. surface
|
Radio outs.
to ins.
|
Weight
|
|
Inch
|
d1
|
d2
|
S1
|
Int. d3
|
Ext. d4
|
d5
|
BWG
|
S2
|
Aa
|
Aa/Ai
|
G Cu
|
|
|
|
mm
|
mm
|
mm
|
mm
|
mm
|
mm
|
|
mm
|
m²/m
|
|
ca. kg/m
|
|
16.1/2.19
16.1/2.18
|
1/2"
|
12,70
|
9,80
9,40
|
1,45
1,65
|
7,50
7,00
|
9,50
|
12,50
|
19
18
|
1,00
1,25
|
0,08
|
3,6
3,8
|
0,38
0,43
|
|
16.5/8.17
16.5/8.16
|
5/8"
|
15,90
|
11,90
11,60
|
2,00
2,15
|
9,70
9,40
|
12,70
|
15,70
|
17
16
|
1,50
1,65
|
0,11
|
3,6
3,7
|
0,65
0,69
|
|
16.3/4.17
16.3/4.16
16.3/4.14
|
3/4"
|
19,00
|
15,00
14,70
14,00
|
2,00
2,15
2,50
|
12,80
12,50
11,60
|
15,80
|
18,80
|
17
16
14
|
1,50
1,65
2,10
|
0,13
|
3,3
3,4
3,6
|
0,83
0,88
1,03
|
|
16.7/8.17
16.7/8.16
16.7/8.14
|
7/8"
|
22,20
|
18,20
17,90
17,20
|
2,00
2,15
2,50
|
16,00
15,70
14,80
|
19,00
|
22,00
|
17
16
14
|
1,50
1,65
2,10
|
0,16
|
3,1
3,2
3,3
|
1,00
1,06
1,25
|
|
16.1.17
16.1.16
16.1.14
|
1"
|
25,40
|
21,40
21,10
20,40
|
2,00
2,15
2,50
|
19,20
18,90
18,00
|
22,20
|
25,20
|
17
16
14
|
1,50
1,65
2,10
|
0,18
|
3,0
3,1
3,2
|
1,18
1,25
1,49
|
19 FINS / INCH FIN PITCH M = 1.33mm
|
19.1/2.21
19.1/2.20
19.1/2.19
19.1/2.18
|
1/2"
|
12,70
|
10,30
10,10
9,90
9,50
|
1,20
1,30
1,40
1,60
|
7,90
7,70
7,50
7,00
|
9,50
|
12,50
|
21
20
19
18
|
0,80
0,90
1,00
1,25
|
0,10
|
4,0
4,1
4,2
4,5
|
0,32
0,34
0,38
0,42
|
|
19.5/8.21
19.5/8.20
19.5/8.19
19.5/8.18
19.5/8.17
19.5/8.16
|
5/8"
|
15,90
|
13,40
13,20
13,00
12,60
11,90
11,60
|
1,25
1,35
1,45
1,65
2,00
2,15
|
11,10
10,90
10,70
10,20
9,70
9,40
|
12,70
|
15,70
|
21
20
19
18
17
16
|
0,80
0,90
1,00
1,25
1,50
1,65
|
0,12
|
3,6
3,7
3,8
4,0
4,2
4,3
|
0,44
0,47
0,51
0,58
0,69
0,74
|
|
19.3/4.20
19.3/4.19
19.3/4.18
19.3/4.17
19.3/4.16
19.3/4.14
|
3/4"
|
19,00
|
16,30
16,10
15,70
15,00
14,80
14,10
|
1,35
1,45
1,65
2,00
2,10
2,45
|
14,00
13,80
13,30
12,80
12,50
11,60
|
15,80
|
18,80
|
20
19
18
17
16
14
|
0,90
1,00
1,25
1,50
1,65
2,10
|
0,15
|
3,5
3,6
3,7
3,8
3,9
4,2
|
0,61
0,63
0,72
0,83
0,88
1,03
|
|
19.7/8.19
19.7/8.18
19.7/8.17
19.7/8.16
19.7/8.14
|
7/8"
|
22,20
|
19,30
18,90
18,20
18,00
17,30
|
1,45
1,65
2,00
2,10
2,45
|
17,00
16,50
16,00
15,70
14,80
|
19,00
|
22,00
|
19
18
17
16
14
|
1,00
1,25
1,50
1,65
2,10
|
0,18
|
3,4
3,5
3,6
3,7
3,9
|
0,80
0,89
1,00
1,07
1,26
|
|
19.1.18
19.1.17
19.1.16
19.1.14
|
1"
|
25,40
|
22,10
21,40
21,10
20,50
|
1,65
2,00
2,15
2,45
|
19,70
19,20
18,90
18,00
|
22,20
|
25,20
|
18
17
16
14
|
1,25
1,50
1,65
2,10
|
0,21
|
3,4
3,5
3,6
3,7
|
1,05
1,19
1,27
1,50
|
26 FINS / INCH FIN PITCH M = 0.97mm
4. T-shaped finned tube material:
|
Material
|
ASTM
|
DIN
|
German Mat.-No.
|
BS
|
Grade
|
|
Carbon Steel
Carbon Steel
Carbon Steel
Carbon Steel
|
A 179
A 192 / A 161 Gr. LC
A 210 Gr. A1
A 210 Gr.C
|
ST 35.8/I
ST 35.8/I
ST 45.8/I
17 Mn 4
|
1.0305 1.0305 1.0405
1.0481
|
3602/1
3059/2
3602/1
3602/1
|
CFS 360
CFS/HFS 360
CFS/HFS 410
CFS/HFS 460
|
|
Low Alloy Steel
Low Alloy Steel
Low Alloy Steel
Low Alloy Steel
Low Alloy Steel
|
A 209 T1
A 213 / A 199 T11/T12
A 213 / A 199 T22
A 213 / A 199 T5
A 213 / A 199 T9
|
16 Mo 5
13 CrMo 44
10 CrMo 910
12 CrMo 195
X12 CrMo 91
|
1.5423 1.7335 1.7380 1.7362
1.7386
|
3606
3604
3059
3604
3059/3604
|
245
621
622-440 625
629-470
|
|
Stainless Steel
Stainless Steel
Stainless Steel
Stainless Steel
Stainless Steel
Stainless Steel
Stainless Steel
Stainless Steel
Stainless Steel
|
A 213 / A 269 / A249 TP 304
A 213 / A 269 / A249 TP 304L
A 213 / A 269 / A249 TP 321
A 213 / A 269 / A249 TP 316
A 213 / A 269 / A249 TP 316L A 213 / A 269 / A249 TP 347
A 213 / A 269 / A249 TP 316Tl
A 789 / A 790 UNS S 31803 B 677 Alloy 904L
|
X5 CrNi 189
X2 CrNi 189
X10 CrNiTi 189
X5 CrNiMo 1810
X2 CrNiMo 1810
X10 CrNiNb 189
X10 CrNiMoTi 1810 X2 CrNiMo 11225
X2 NiCrMoCu 25205
|
1.4301 1.4306 1.4541 1.4401 1.4404
1.4550
1.4571
1.4462
1.4539
|
970
970
970
970
970
970
970
–––
–––
|
304 S 15
304 S 12
321 S 12
315 S 16
316 S 12
347 S 17
320 S 17
|
|
Nickel
Nickel
|
B 161 UNS No 2200
B 161 UNS No 2201
|
Ni 99,2
Ni 99,2
|
2.4066
2.4068
|
3074
3074
|
NA 11
NA 12
|
|
Nickel-Copper
|
B 163 N 04400
|
NiCu30Fe
|
2.4360
|
3074
|
NA 13
|
|
Nickel-Chrom-Iron
Nickel-Chrom-Iron
Nickel-Chrom-Iron
Nickel-Chrom-Iron
|
B 163 6600
B 161 8825
B 468 08020
B 163 08800
|
NiCr15Fe
NiCr21Mo
––– X10 NiCrAlTi 3220
|
2.4816 2.4858
1.4876
|
3074
3074 ––– 3074
|
NA 14
NA 16
NA 15
|
|
Copper Alloy
Copper Alloy
Copper Alloy
Copper Alloy
Copper Alloy
Copper Alloy
Copper Alloy
|
B 75 / B 111 UNS C12200
B 75 / B 111 UNS C14200 B 111 UNS C44300
B 111 UNS C68700
B 111 UNS C60800
B 111 UNS C70600
B 111 UNS C71500
|
Sf-Cu
CuAsp
CuZn28Sn1
CuZn20Al2
CuAl5AS
CuNi10Fe1Mn
CuNi30Mn1Fe
|
2.0090 2.1491 2.0470 2.0460 2.0918 2.0872
2.0882
|
2871
2871
2871
2871 ––– 2871
2871
|
C 106
C 107
CZ 111
CZ 110
CN 102
CN 107
|
|
Aluminium Alloys
Aluminium Alloys
Aluminium Alloys
Aluminium Alloys
|
Alloy 1050 / 1050A
Alloy 5754
Alloy 3003
Alloy 5083
|
Al 99,5
AlMg3
AlMnCu
AlMg4,5Mn
|
3.0255 3.3535 3.0517
3.3547
|
1050A (1B)
(N5)
––– 5083 (N8)
|
|
|
Titanium
|
B338 Gr. 2
|
Ti2
|
3.7035
|
|
|
5. Applicable scope of T-shaped finned tube:
As long as the shell side medium is clean, free of solid particles and gums, T-shaped finned tubes can be used as heat exchange elements to form T-shaped finned tube high efficiency heat exchanger to improve the boiling heat transfer effect at the shell side. T-shaped finned tube is applicable to the working conditions of shell side boiling heat transfer in petrochemical, energy and other industrial fields. It is not applicable to the medium with solid dust and easy coking in the shell.
T-shaped finned tube|Low fin tube
|
