Working Principle of Water Inlet and Outlet in Rotary Joints

Working Principle of Water Inlet and Outlet in Rotary Joints

1. Steam Rotary Joints
Steam rotary joints, also known as high-temperature rotary joints, have a unique structure. Steam is typically introduced through a side port, while an internal pipe functions as a siphon tube to discharge condensate.

The quality of drainage directly affects the roller temperature. The siphon tube usually consists of a hard pipe segment and a flexible hose. The hard pipe extends deep into the roller, while the hose droops near the roller's inner wall. Under steam pressure, the condensate is pushed out efficiently.

2. Heat Transfer Oil Rotary Joints (Single-Side Setup)
When using heat transfer oil, dual-flow rotary joints are used on single-sided equipment. Oil enters through the inner pipe and exits through the housing’s surrounding ports.

To maintain uniform roller temperature, the inner pipe is extended beyond half the roller's length and perforated at the end. A larger inner pipe and smaller outlet help ensure the roller stays fully filled with oil.

3. Double-End Rotary Joint Setup
If the roller has a joint installed on both ends, the setup is much simpler. Identical rotary joints can be used on both sides, and the direction of flow doesn’t matter.

4. Water Rotary Joints
The working principle of rotary joints for water is similar to that for thermal oil. In a single-sided installation, a dual-flow rotary joint uses the inner pipe for water inlet. The inlet flow rate is higher than the outlet to keep the roller filled with water.

Even in dual-end setups, due to the pressurized inlet (usually via a pump), identical joints on both ends can still ensure faster inlet than outlet, keeping the system full of water.