The VC (Vapor Chamber) sealing machine is seal device designed for semi-finished vapor chambers equipped with a shell, a capillary wick structure, and a support structure. The sealing process includes steps such as injecting working fluid into the semi-finished vapor chamber, freezing and solidifying the fluid, vacuum degassing, and sealing. The sealing device consists of a freezing end assembly, a refrigeration source, a refrigerant pipeline, a vacuum pump unit, a vacuum pipeline, a sealing end clamping fixture, and other components. It can provide processes of freezing and solidification, vacuum pumping, and sealing under a vacuum environment, featuring a simple structure, high production efficiency, and high product yield. It is suitable for automated and mass production. The vapor chambers manufactured by our machine can achieve an extremely high internal vacuum degree, with almost no loss of phase change working fluid, minimal residual non-condensable gases, and high production efficiency.
With the rapid expansion of the electronic product market, the demand for vapor chambers is growing increasingly. The market requires large-scale production and reduced application costs. Based on long-term experience in the development of vapor chambers, the filling accuracy of phase change working fluid and the degassing condition are key factors affecting the performance and stability of micro heat pipes. To avoid excessive temperature difference between the evaporation end and condensation end of the vapor chamber, it is necessary to further remove the internal non-condensable gases, a process known as the secondary degassing method. Currently, the liquid filling and degassing processes for vapor chambers have many problems, such as inaccurate filling volume of phase change working fluid, insufficient internal vacuum degree, residual non-condensable gases, and complex processes. These issues result in low yield, low production efficiency, and high costs of finished flat heat pipes, which hinder their application and promotion. Therefore, it is of great significance to seek solutions to the problems in the liquid filling and degassing process, a key technology in vapor chamber manufacturing.
Our VC sealing machine can produce vapor chambers of various thicknesses, complex shapes, and internal structures, and is equally effective for vapor chambers with a wall thickness of less than 0.6mm. The vapor chambers manufactured by our machine can achieve an extremely high internal vacuum degree, with almost no loss of phase change working fluid and minimal residual non-condensable gases. Moreover, it can effectively control the length of the sealing end within the range of 0-2mm, greatly reducing the installation space required for the vapor chamber and enabling its application in ultra-thin mobile terminals with high PCB integration. Our device has a simple structure, high production efficiency, and high product yield, making it suitable for automated and mass production, thereby reducing product costs and facilitating large-scale promotion.
The object to be sealed by the VC sealing machine is a semi-finished vapor chamber with a shell, a capillary wick structure, and a support structure. The semi-finished product is reserved with an opening for working fluid injection and vacuum pumping before sealing. It is characterized by comprising a freezing end assembly (2), a refrigeration source (3), a refrigerant pipeline (4), a vacuum pump unit (5), a vacuum pipeline (6), a sealing end clamping fixture (7), and a valve (8), wherein:
The freezing end assembly (2) is located on both sides of the semi-finished vapor chamber (1), and sealing end clamping fixtures (7) are arranged on both sides of the reserved opening (9) of the semi-finished vapor chamber;
The freezing end assembly (2) and the sealing end clamping fixture (7) are placed inside a vacuum chamber (10), while the refrigeration source (3) and the vacuum pump unit (5) are placed outside the vacuum chamber. The refrigeration source (3) is connected to the freezing end assembly (2) through the refrigerant pipeline (4), the vacuum pump unit is connected to a vacuum pumping port (11) through the vacuum pipeline, and the vacuum pumping port (11) is arranged on the wall of the vacuum chamber (10);
The refrigeration source (3) is an external refrigeration device that delivers refrigerant into the freezing end assembly (2) through the refrigerant pipeline (4); the freezing end assembly (2) freezes the semi-finished vapor chamber through heat convection and radiation without contacting it, or directly contacts the semi-finished vapor chamber for freezing through heat conduction, or freezes it by filling a heat-conducting medium between the freezing end assembly and the semi-finished vapor chamber.
The refrigeration source (3) can be one of a semiconductor thermoelectric cooling chip device, a cryogenic equipment, or a cryopump.
The sealing end clamping fixture (7) may or may not be equipped with a heating element inside.
The thickness of the sealing end clamping fixture (7) is ≤ 5mm.
When the freezing end assembly (2) freezes the vapor chamber through direct contact heat conduction, it is embodied in at least one of the following forms of frozen flat metal plates:
a. A frozen metal plate with built-in refrigerant channels; b. A frozen metal plate with refrigerant coils welded on the back; c. A metal plate with holes for refrigerant coils to pass through; d. A double-layer metal plate with two pieces of semi-hole channels clamping the refrigerant coils; e. A combined metal plate where refrigerant coils are welded between two or more independent metal plates; f. A semiconductor thermoelectric cooling chip or a metal plate bonded with a semiconductor thermoelectric cooling chip.
The sealing end clamping fixture (7) is connected to hydraulic, pneumatic, or electric equipment, and the opening, closing, and clamping actions of the sealing end clamping fixture are controlled through its movable components.
The sealing end clamping fixture (7) itself serves as a welding component for welding and sealing, or the welding component is arranged above the sealing end clamping fixture (7).
Advantages of Our Machine
Our machine adopts a scheme of first injecting liquid working fluid into the vapor chamber, then freezing the liquid working fluid into a solid, and finally pumping vacuum to the set working vacuum degree of the vapor chamber, which can minimize the vaporization loss of the working fluid during vacuum pumping. This is because the boiling point of a liquid decreases with the reduction of air pressure. In the manufacture of vapor chambers, it is necessary to ensure that the internal air pressure is below 100Pa; the lower the air pressure, the easier the liquid working fluid is to vaporize. The vaporized working fluid is taken away by the vacuum pumping equipment, resulting in insufficient filling of phase change working fluid inside the vapor chamber and affecting its thermal conductivity.
The traditional technical scheme offsets this loss by estimating the loss during vacuum pumping and filling an excessive amount of liquid working fluid in the initial filling. However, in actual operation, the pumping time of the vacuum equipment is greatly affected by environmental temperature and humidity as well as the equipment's own state. It is difficult to achieve consistent pumping time between different batches of vapor chambers, and the filling volume of phase change working fluid inside different vapor chambers varies greatly, leading to low yield of finished vapor chambers.
Our equipment first freezes the liquid working fluid into a solid, and then pumps the vacuum to the set working vacuum degree of the vapor chamber. The vaporization amount of the solid working fluid during the vacuum pumping process is extremely small, which allows precise control of the phase change working fluid filled in the finished vapor chamber and improves the yield of finished vapor chambers. Meanwhile, our machine is not affected by the thickness, shape, or internal structure of the vapor chamber.
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Written by
CoolingThermal Engineering TeamCoolingThermal is an automation equipment manufacturer based in Kunshan, China, specializing in heat pipe and vapor chamber production equipment since 2017. Our engineering team designs, builds, and commissions complete production lines covering forming, degassing, welding, testing, and assembly processes. The technical content on this blog is written by the same team that develops the equipment — based on real production experience, not secondary research.
