Rotary unions are an essential component of many industrial processes. These devices allow for the transfer of fluid, gas, or electrical power from a stationary source to a rotating component. They are used in a variety of applications, from printing presses and packaging machinery to machine tools and robotics. In this blog post, we will take a closer look at rotary unions, what they are, how they work, and their different types and applications.

What is a Rotary Union?

A rotary union, also known as a rotary joint, is a device that allows for the transfer of fluid or gas from a stationary source to a rotating component. It is designed to maintain a leak-free seal between the stationary and rotating parts. Rotary union is used in applications where it is necessary to transfer fluids or gases between a fixed component and a rotating one. They are also used for the transfer of electrical power, signals, or data.

Rotary unions are made up of two main parts: a stationary part and a rotating part. The stationary part is usually mounted to a fixed surface, while the rotating part is mounted to the rotating component. The two parts are connected by a sealed pathway that allows for the transfer of fluid or gas.

How Does a Rotary Union Work?

Rotary unions work by using a sealed pathway to transfer fluid or gas from a stationary source to a rotating component. The stationary part of the rotary union is connected to the stationary source, while the rotating part is connected to the rotating component. As the rotating component spins, the sealed pathway allows for the transfer of fluid or gas between the two parts.

The sealed pathway in a rotary union is usually made up of multiple channels or passages. These channels or passages are designed to maintain a leak-free seal between the stationary and rotating parts. The sealed pathway can be designed to transfer a variety of fluids, gases, or other media, depending on the application.

Types of Rotary Unions

There are several types of rotary unions available, each designed for specific applications. Some of the most common types of rotary unions include:

  • Single passage rotary unions: These are the simplest type of rotary union, with a single passage for the transfer of fluid or gas.
  • Multi-passage rotary unions: These have multiple passages or channels, allowing for the transfer of multiple fluids or gases.
  • Electrical rotary unions: These are used for the transfer of electrical power, signals, or data between a stationary source and a rotating component.
  • Hybrid rotary unions: These combine the transfer of fluid or gas with the transfer of electrical power, signals, or data.
  • High-pressure rotary unions: These are designed for applications that require the transfer of fluids or gases at high pressures.
  • High-speed rotary unions: These are designed for applications that require the transfer of fluids or gases at high speeds.

Applications of Rotary Unions

Rotary unions are used in a variety of applications, from printing presses and packaging machinery to machine tools and robotics. They are used in any application where it is necessary to transfer fluids, gases, or electrical power between a stationary source and a rotating component.

In the printing industry, rotary unions are used to transfer ink and water from a stationary source to the rotating printing cylinder. In the packaging industry, they are used to transfer adhesives, coatings, and other fluids to the packaging materials. In the machine tool industry, they are used for the cooling and lubrication of cutting tools. In robotics, rotary unions are used for the transfer of hydraulic fluid or pneumatic power to robotic arms.

Rotary unions are also used in the manufacturing of semiconductors, where they are used to transfer fluids and gases to process chambers. They are used in the food and beverage industry for the transfer of liquids and gases, such as the transfer of carbon dioxide to carbonated beverages.

In conclusion, rotary unions are a crucial component of many industrial processes, allowing for the transfer of fluid, gas, or electrical power from a stationary source to a rotating component. There are several types of rotary unions available, each designed for specific applications, including single passage rotary unions, multi-passage rotary unions, electrical rotary unions, hybrid rotary unions, high-pressure rotary unions, and high-speed rotary unions. These devices are used in a wide range of industries, including printing, packaging, machine tooling, robotics, semiconductor manufacturing, and food and beverage. Understanding how rotary unions work and their different types and applications can help businesses choose the right rotary union for their specific needs.