modernrotaryjoint08 – https://modernrotaryjoint.com/what-is-a-rotary-union/

In many industries, fluid or gas transfer is an essential component of machinery operation. Consider the example of a large-scale printing press: it needs a consistent supply of ink, which must be delivered under pressure to the moving rollers, or take the case of an automated production line that requires a continuous stream of air for robotic arms. The real challenge in these situations lies in providing the necessary fluid or gas flow between stationary and rotating components without causing leaks or interruptions. The solution to this challenge? Rotary unions.