COFAN THERMAL

HEAT PIPES

COFAN’S HEAT PIPES ARE SUPERCONDUCTORS WITH EXTRAORDINARY HEAT TRANSFER CAPACITY.

Cofan’s heat pipe is a thermal management device designed to transfer heat efficiently from one point to another using the principles of phase transition and thermal conductivity. It consists of a sealed hollow tube containing a working fluid and a wick structure that facilitates the movement of the fluid within the tube.
Typically, a heat pipe includes three main components: the container, the working fluid, and the wick structure. The container, usually made of metal such as copper or aluminum, provides the structure and holds the working fluid. Inside the container, the working fluid, which can be water, ammonia, acetone, or various refrigerants, undergoes phase changes to transfer heat. The wick structure, made from materials like sintered metal, screen mesh, or grooved surfaces, lines the inner walls of the container and aids in the capillary action needed to return the condensed fluid back to the evaporator section.
Cofan’s heat pipe operates by utilizing phase transition and capillary action. When heat is applied to one end of the heat pipe (the evaporator section), the working fluid absorbs the heat and evaporates, turning it into vapor. This vapor then travels along the length of the heat pipe to the cooler end (the condenser section) due to the pressure difference created by the evaporation process. At the condenser section, the vapor releases its heat to the surroundings, condenses back into a liquid, and is absorbed by the wick structure. The wick structure then uses capillary action to return the condensed liquid back to the evaporator section, allowing the cycle to continue.
Cofan’s Heat pipes offer several advantages. They have high thermal conductivity, allowing for the transfer of heat over long distances with minimal temperature drop, far superior to solid conductors of the same size. They operate passively, relying on natural physical processes without the need for external power. Additionally, heat pipes are flexible and can be bent and shaped to fit various applications, making them highly versatile. They also provide efficient heat distribution along their length, which is beneficial for temperature-sensitive components.
Heat pipes are used in a wide range of applications, including electronics cooling in laptops, desktops, and servers to cool CPUs, GPUs, and other heat-generating components. In aerospace, they are used for temperature control in satellites and spacecraft. They also play a role in managing the heat generated by high-power LED lights, improving energy efficiency in HVAC systems, and cooling sensitive equipment in medical devices.

- HEAT PIPE

Type: Sinterted
Brand Name: Cofan Thermal
Place of Origin: Dongguan, China
Application: Thermal Management
Delivery Time: 4 Weeks L/T

- Product Information -

Place of Origin:
Dongguan, China
OEM:
Yes
Process:
Flat, Bending, Post Machining
Brand Name:
Cofan Thermal
Material:
Copper
Shape:
As Drawing
Application:
Thermal Management
Size:
As Drawing
Finish:
Anti-Oxidant
Delivery TIme:
4 Weeks L/T

- HEAT PIPE

Type: Sinterted
Brand Name: Cofan Thermal
Place of Origin: Dongguan, China
Application: Thermal Management
Delivery Time: 4 Weeks L/T

- Product Information -

Place of Origin:
Dongguan, China
OEM:
Yes
Process:
Flat, Bending, Post Machining
Brand Name:
Cofan Thermal
Material:
Copper
Shape:
As Drawing
Application:
Thermal Management
Size:
As Drawing
Finish:
Anti-Oxidant
Delivery TIme:
4 Weeks L/T

- HEAT PIPE

Type: Sinterted
Brand Name: Cofan Thermal
Place of Origin: Dongguan, China
Application: Thermal Management
Delivery Time: 4 Weeks L/T

- Product Information -

Place of Origin:
Dongguan, China
OEM:
Yes
Process:
Flat and Bending
Brand Name:
Cofan Thermal
Material:
Copper
Shape:
As Drawing
Application:
Thermal Management
Size:
As Drawing
Finish:
Anti-Oxidant
Delivery TIme:
4 Weeks L/T

Feature included:

  • High conductivity (5,000 watts/meter·K to 200,000 watts/meter·K)
  • Energy-efficient
  • Lightweight
  • Low cost
  • Flexibility of many different size and shape options
  • 100% Inspection of all heat pipes, before and after bending
  • Passed stringent heat transfer tests to reach a minimum temperature grade within a minimal time period (Delta ΔT; 4 degrees C, time period ~ 7 seconds
  • Longest heat pipe on the market, all the way up to 4700 mm

What are heat pipes?

A heat pipe is composed of a vacuum-tightened vessel, a wick structure, and some amount of working fluid. As heat is inputted at the evaporator, the fluid vaporizes, creating a pressure gradient. This pressure gradient pushes the vapor to flow along the pipe to the cooler section where it condenses, giving up its latent heat of vaporization. The working fluid is then returned to the evaporator by capillary forces developed in the wick structure or by gravity.

Main components:

  • Container
  • High strength, high thermal conductivity
  • Working fluid
  • High latent heat, high thermal conductivity
  • Wick/capillary structure
  • State-of-the-art copper powder sintering for maximum performance
  • Maintains effective capillary action when bent or used against gravity

Heat is absorbed from the source through vaporization and released at a sink through condensation. The vapor travels from source to sink through the central channel, while the liquid travels from sink to source through the porous wick.

The rapid growth of the electronics and personal computer industries has introduced challenging heat dissipation problems. Heat pipes effectively transport heat with minimal drops in temperature.

Typical applications

  • Laptop computers
  • High-performance processors (CPU, GPU)
  • Aerospace; spacecraft temperature equalization, component cooling
  • Constrained geometries
  • Low maintenance/high-reliability applications
  • Noise-sensitive environments where heat can be dissipated to a larger, remote heat sink
  • Stagnation regions where airflow is poor
  • Limited electrical consumption
  • Passive solution to conserve battery power
Wick Structure
Standard Length/mm
Special Length/mm
Performance 100-350 L/mm
Mesh
Groove
Sintered
60-120
121-200
210-400
601-4700
Power/W
Terminal resistance ℃/w
⌀2
3-6
0.62-1.66
⌀3
10-15
0.33-0.5
⌀4
15-28
0.17-0.33
⌀5
● (Groove & Mesh)
30-50
0.1-0.2
⌀6
● (Groove & Mesh)
50-70
0.07-0.15
⌀8
● (Mesh)
60-90
0.05-0.1
⌀10
● (Mesh)
130-160
0.03
⌀12
● (Mesh)
130-160
0.03
⌀14
● (Mesh)
180-220
0.08

Wick structure comparison

Wick Structure
Screen Mesh
Groove
Sintering Podwer
Image
Rate Process
Easy
Easy
Hard
Capillary
Bad
Good
Better
Flat (Min.)
t = 2.0
t = 1.5
t = 2.5
Bend (Min.)
2* Heat Pipe Diameter [D]
2* Heat Pipe Diameter [D] ~
2* Heat Pipe Diameter [D]
3* Heat Pipe Diameter [D]
Resistance (t = 3mm)
.250 ~ .350
.03 ~ .040
.030 ~ .045
Heat Flux
35
40
45
Cost
Low
Medium
High

Heat pipes in stock

Diameter x Length [mm]
Part No.
Diameter x Length [mm]
Part No.
Diameter x Length [mm]
Part No.
Diameter x Length [mm]
Part No.
4 x 70
91-1028-70
5 x100
91-1029-100
6 x 125
91-1030-125
8x 125
91-1031-125
4 x 175
91-10280175
5 x 125
91-1029-125
6 x 150
91-1030-150
8 x 150
91-1031-150
4 x 100
91-1028-100
5 x 150
91-1029-150
6 x 170
91-1030-170
8 x 175
91-1031-175
4 x 125
91-1028-125
5 x 175
91-1029-175
6 x 200
91-1030-200
8 x 200
91-1031-200
4 x 200
91-1028-200
5 x 200
91-1029-200
6 x 225
91-1030-225
8 x 300
91-1031-300
4 x 250
91-1028-250
5 x 225
91-1029-225
6 x 250
91-1030-250
4 x 225
91-1028-225
5 x 225
91-1029-250
6 x 300
91-1030-300
4 x 300
91-1028-300
5 x 300
91-1029-300

Heat pipes working fluid

How to select a working fluid:

  • High surface tension – generates high capillary force and resists the environment.
  • High Vapor pressure – reduces vapor velocity.
  • High latent heat – transfers more heat with less fluid.
  • High thermal conductivity – lower ΔT and reduces nucleate boiling at the wick/wall interface.
  • Low vapor viscosity – increases fluid flow capacity.
Working Fluid
Relative Figure of Merit [80ºC]
Useful Range [ºC]
Wick Vessel Material
Life [hrs]
Ammonia
.45
- 60 ~ 100
AL SS304
36000
Ammonia
.45
- 60 ~ 100
AL SS304
36000
Freon 113
86
- 10 ~ 100
CU AL SS304
25000
Aceton
300
0 ~ 120
CU AL SS304
50000
Methanol
450
10 ~ 120
CU AL SS304
less than 50000
Ethanol
340
0 ~ 120
CU SS304
24000
Water
40000
30 ~ 250
CU
7500000

COFAN Thermal's flexible solutions:

  • The lead time of less than one week for various diameters and lengths
  • Copper; multiple plating options available to suit the application
  • Custom bending done in-house for use in any hardware layout
  • Various heat pipe diameters
  • Various heat pipe lengths of up to 600 mm

Copper screen mesh

Assessment Parameter
Diameter (mm)
Diameter (mm)
Diameter (mm)
Diameter (mm)
Thickness
4
5
6
8
t = 2.0 mm
.65 ~ .09; 15
.50 ~ .80; 18
.35 ~ .60; 35
.30 ~ .55; 45
t = 2.5 mm
.55 ~ .08; 18
.45 ~ .65; 22
.25 ~ .40; 40
.20 ~ .35; 50
t = 3.0 mm
.50 ~ .70; 20
.45 ~ .60; 22
.25 ~ .35; 45
.20 ~ .30; 55
Round
.50 ~ .70; 20
.40 ~ .35; 25
.20 ~ .35; 45
.15 ~ .30; 60
Units; R [ºC/W]; Qmax [Watt]

Copper Groove

Assessment Parameter
Diameter (mm)
Diameter (mm)
Diameter (mm)
Diameter (mm)
Thickness
4
5
6
8
t = 2.0 mm
.40 ~ .70; 5
.40 ~ .60; 5
t = 2.5 mm
.04 ~ 06; 25
.03 ~ .05; 40
t = 3.0 mm
.02 ~ .05; 30
.03 ~ .04; 60
t = 4.5 mm
.003 ~ 0.15; 70
Round
.03 ~ .05; 35
.20 ~ .03; 65
.002 ~ .007; 80
Units; R [ºC/W]; Qmax [Watt]

Copper sintering powder

Assessment Parameter
Diameter (mm)
Diameter (mm)
Diameter (mm)
Diameter (mm)
Thickness
4
5
6
8
t = 2.0 mm
.035 ~ .60; 5
t = 2.5 mm
.04 ~ 06; 25
.03 ~ .05; 40
t = 3.0 mm
.02 ~ .05; 30
.03 ~ .04; 60
t = 4.5 mm
.003 ~ 0.15; 70
Round
.03 ~ .05; 35
.20 ~ .03; 65
.002 ~ .007; 80
Units; R [ºC/W]; Qmax [Watt]

Customized bending & flattening

Diameter, D [mm]
3
4
5
6
8
9
9.6
10
12
12.7
16
Minimum Bending Radious [2*D]
6
8
10
12
16
18
19
20
24
25
32
Standard Bending Radious [3*D]
9
12
15
18
24
27
29
30
36
38
48
Recommended Bending Radious [4*D]
12
16
20
24
32
36
38
40
48
51
64
Minimum Bending Angle [⌀]
90º
Recommended Bending Angle [⌀]
120º
Diameter (mm)
Thickness, t+0.05/-0.10 [mm]
DiamWidth, W ± 0.15 [mm]
3
1.2
3.94
1.5
4.10
2.0
3.65
2.5
3.32
3.0
N/A
4
1.5
5.49
2.0
5.23
2.5
4.96
3.0
4.65
4.0
N/A
5
1.4
7.14
1.5
6.77
2.0
6.60
2.3
6.50
2.5
6.26
3.0
5.95
4.0
5.63
5.0
N/A
6
1.5
8.69
2.0
8.41
2.3
8.25
2.4
8.20
2.5
8.16
2.7
8.00
3.0
7.84
3.5
7.57
4.0
7.30
4.8
6.86
5.0
6.63
5.3
6.60
6.0
N/A
8
2.0
Undone
2.5
11.26
3.0
10.97
3.5
10.71
4.0
10.45
4.5
10.20
5.0
9.96
6.0
9.36
8.0
N/A
Need something special? Talk to our engineers today!
Scroll to Top