Rotary joints are also known as rotating unions or rotative joints. They provide a mechanical seal between the stationary supply pipe and a rotating cylinder or drum. Thus, the main purpose of it is to allow the flow of heat transfer media in and out of the roller rotary.
Typically, water, steam, hydraulic oil, thermal oil, or coolant is used as heat transfer media.
In mechanical applications, rotary joints can be designed with multiple passages. They can manage several media types at a time. To stop the crossover of fluids, soft seals, like an O-ring is used.
Soft seal multi-passage rotary unions are used in a variety of industries and applications, e.g., oil and gas, food and beverages, robotics, medical applications, and so on.
To transmit hydraulic power or electrical signals, the rotary joints are fitted with slip rings.
With conventional rotary joints, a spring-loaded seal is used to keep the fluid or gas medium from leaking into the surroundings. The spring is a very critical part of a steam rotary joint. It maintains the initial internal seating. Also, the rotary joint gets pressure-sealed once in operation.
Vacuum services or low-pressure services rely on the spring force because it creates the seal.
In conventional rotary joints, either there is an external support of mounting brackets or rods. In some cases, they are self-supported with the help of an internal carbon guide.
Applications of rotating joints
Rotating joints are very common in any industrial environment. They are very useful elements for all types of fluids. They are useful in varied pressure situations.
Rotary joints for water, for example, can work in a variety of pressure situations. The degree of precision of its mechanical elements is marked by the type of application.
As far as applications are concerned, these joints are very useful in industrial applications like the paper industry, the cardboard industry, oil and refineries, food and beverages, the chemical industry, and so on.
Balanced seal rotary unions are generally used with fluid services like coolant or water. However, they can be used with steam and other gases as well.
This technology relies on the optimization of spring pressure to create a positive seal within the rotary union.
There is very little operating pressure on the media and less effect on the seal load. In balanced seals, there are typically flat face seals, and rotary joints are supported by ball bearings. Thus, rotary joints are one of the most useful components.