WHAT IS ROTARY JOINT?

A rotary joint, also known as a rotary joint or rotary joint, is a mechanical device used to transfer a fluid, such as a liquid or gas, between a fixed part and a rotating part. It is a key component in many industrial and mechanical systems, especially those involving rotating machinery. Here is a detailed description of the rotary joint and how it works:

Definition of  rotary joint
A rotary joint is a sealed connection that continuously transfers fluids (e.g., oil, water, air, steam) from a stationary source to a rotating part without leakage. Even if the connected parts rotate relative to each other, it ensures that the fluid can flow smoothly and continuously.

Key component
1. Shell:
– Function: fixed part of the rotary joint connected to the fluid supply.
Material: Usually made of materials such as steel, stainless steel or brass, depending on the application and the type of fluid being transferred.

2. Axis:
– Function: The rotating part of a rotary joint, connected to a rotating device, such as a drum, roller or spindle.
– Material: Usually made of steel or stainless steel to ensure durability and wear resistance.

3. Sealing parts:
– Function: Prevent fluid leakage between the fixed housing and the rotating shaft. Seals must withstand pressure, temperature and friction while maintaining a tight seal.
– Type:
– Lip seals: Simple and effective, often used in low pressure applications.
– Mechanical end seals: Provide a more robust seal for high pressure and high speed applications.
– Packing seals: made of woven or molded material, adjustable for tighter seal.
O-ring: Used with other seals to provide additional sealing.
– Material: Usually made of elastomers such as NBR (nitrile), FKM (fluororubber) or PTFE (Teflon), depending on the fluid and operating conditions.

4. Bearing:
– Function: Support the rotating shaft and ensure smooth, low friction movement. They help keep axes aligned and reduce fatigue.
– Type:
– Ball bearings: suitable for light to mass loads and high speeds.
Roller bearings Bearings: can withstand heavier loads and are more durable.
– Plain bearings: simple and cost-effective, often used in low-speed applications.
– Material: Usually made of steel or bronze, some special applications use ceramic or plastic bearings.

Fluid flow path
– Radial flow: In a radial flow design, fluid enters the housing and flows radially outside toward the axis of rotation. This design is common in applications where fluid flow needs to be evenly distributed over the axis circumference.
Compact flow: In a symmetrical flow design, fluid flows in series along an axis, entering from one end and interrupting from the other or flowing through the center of the axis. This design is suitable for applications that require a linear fluid path.

Type of rotary joint
one. Unidirectional swivel joint: Fluid is only allowed to transfer in one direction.
2. Headphone swivel: allows fluid to be transmitted in both directions without mixing fluid.
3. Multi-direction rotary joint: can handle a variety of fluids at the same time, will them
4. Hydraulic swivel joint: Designed for hydraulic applications and can handle high pressure. 5. Pneumatic rotary joint: For
Air or vacuum applications, often used in automated machinery.

Application of rotary joint
Industry: Used in paper mills, textile machines and printing presses.
– Automotive industry: for steering machinery systems, power Windows and other rotating parts.
– Aerospace: For aircraft landing gear, flaps and other rotating parts.
– Chemical processing: for reactors, agitators and other process equipment.
– Food and beverage: processing equipment critical for hygiene and anti-contamination.

Maintenance and inspection
– Regular inspection: Check for fatigue, leakage or misalignment. Inspect seals, bearings and housings for damage.
Lubrication: Ensure that bearings and seals are properly lubricated to reduce friction and fatigue.
– Replacement: Timely replacement of worn or damaged parts to prevent further problems and ensure continued performance of rotary joints.

By understanding the functions and components of rotary joints, you can better select and maintain the right type for your specific application, ensuring reliable and smooth transfer in rotary systems.