The CT tube, the central component of CT, can be regarded as the lifeblood of the trillion-yuan imaging market.

Its superiority or inferiority not only determines the performance level of the entire CT machine to a certain extent, but is also often regarded as the key to reducing the gap between high-end products and imported brands.
However, due to the complex technology and high process requirements of CT central components such as tubes, as well as the need for customization in most consumer equipment, this component has not yet been fully domesticated. For a long time, most domestic imaging manufacturers did not have the ability to independently research and produce core components, and the core components of domestic high-end products were mostly imported products.
From the perspective of the development history of ball tube technology, traditional CT ball tubes usually adopt ball bearings. However, the emergence of liquid metal bearing technology in the 1990s gradually replaced ball bearings and became the mainstream application in high-end CTS in the first two decades of the 21st century.
Compared with traditional ball bearings, the use of liquid metal bearings can bring at least four advantages:
(1) Greatly enhance the heat dissipation rate. That is, under the target disk structure with the same physical heat capacity, the equivalent heat capacity can be greatly enhanced.
(2) The centripetal force that liquid metal sliding bearings can withstand during frame rotation can reach 30-40g, which can support faster frame rotation and imaging rates, and has a significant advantage in cardiac scanning.
(3) As the bearing core does not come into direct contact with the outer sleeve during operation, the wear is small, and its service life is at least twice as long as that of ball bearings.
(4) The liquid metal sliding bearing has no contact and operates in perfect and silent condition.
With the continuous maturation of liquid metal bearing technology and the reduction of mass production manufacturing costs in recent years, the application of liquid metal bearings is no longer limited to high-end CTS and has begun to move towards mid-range models. Its application scenarios and market space have become increasingly common.
However, the production and manufacturing of key components of liquid metal bearing CT ball tubes involve over 30 processes throughout the entire production process. The key technical issues encountered cover various aspects such as design, materials, processing, welding, vacuum, surface treatment, and fine assembly. It is particularly difficult to break through these key technologies.