As we know customers using rotary joints are not complicated working conditions, but high requirements for products. Many of these problems are not clear about the function and classification of rotary joints, leading to errors in the selection of rotary joints.

First understand the purpose of the selected rotary union. It is a transitional connection sealing device that inputs a fluid medium from a static state into a rotating device, It is a relatively moving sealing device, and its important feature is that it is composed of two parts: a stationary part and a rotating part.

• Classification of rotary joints. Common types include fluid medium, seal type, medium temperature, pressure, rotation speed and number of channels etc. Rotaryjoints according to different fluid media, include hydraulic rotary joints, thermal oil rotary joints, water rotary joints, steam rotary joints, compressed air rotary joints and other rotary joints.
• Rotary Joint according different channel, include single channel swivel, double channel swivel and multi-channel swivel. The multi-channel rotary joint is generally a rotary joint with more than three channels.
• Different rotary joint seal type. Include ring seal rotary joint, mechanical seal rotary joint and clearance seal rotary joint and other types. Sealing type rotation is usually affected by many factors such as the medium temperature, pressure and rotation speed of the rotating joint.
• Different pressure, negative pressure, low pressure, medium pressure and high pressure rotary joints. Under normal circumstances, in the case of vacuum, it is necessary to rotate the joint to withstand negative pressure. The rotary joint on our common heating and cooling equipment usually needs to withstand low pressure, and the pressure difference between the inlet and outlet of the rotary joint is directly generated, allowing the fluid to flow. And hydraulic equipment because of the large torque, need to withstandacertain medium pressure, high pressure, so that the hydraulic equipment can operate normally.
• Different temperature, normaltemperature rotary joint, high temperature rotary joint and low temperature rotary joint. Rotating joints through different temperature media, such as heating, cooling or cleaning. In addition, some high-pressure rotary joints, the seal will heat up when rotating at high speed, so the rotary joints are also required to withstand high temperatures.
• Different speed. Low speed, middle speed and high speed. According to the rotating speed of the rotating equipment, the rotating joint should be adapted to the rotating speed working requirements
• Different speed. Low speed, middle speed and high speed. According to the rotating speed of the rotating equipment, the rotating joint should be adapted to the rotating speed working requirements.

The selection of rotary joint, we according to its different classification requirements, rotary selection of suitable products, can give full play to the performance of the product, extend the service life, but also improve the efficiency of the equipment.