What is the difference between Rotary Joints and Rotary Unions?

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What is the difference between Rotary Joints and
Rotary Unions?
Visit What is the difference between Rotary
Joints and Rotary Unions?
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Lets understand this important industrial
equipment in detail.
In industrial equipment, several types of tools
and parts are being used. Each one has some
unique purpose and usage. You might have heard
about rotary joints and rotary unions several
times. They are widely used in various
industries, such as Textile, Paper, Food,
Aluminum, Automotive, Cement, Leather, Plastics,
Packaging, etc.

• Rotary joints are also known as rotary unions or
  rotating unions.
• It is a rotary sealing device. The purpose of
  this part is to connect rotating equipment to
  fixed piping for the transfer of water, coolant, h
  ydraulic oil, steam, air, or any other media.

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• It is possible to design them with several types
  of passages so that multiple media types can be
  managed simultaneously.
• In this case, a soft seal is used to prevent the
  fluids from crossing over into another passage.
  Typically, it is an O-ring.
• In many industrial applications, soft
  seal multi-passage rotary unions are used widely.
  They are widely used in the oil and gas
  industries, food and beverage industries, medical
  devices, and even robotics.
• You can find applications, where the rotary union
  is fitted along with slip rings. The purpose is
  to transmit electrical signals or hydraulic
  power.
• In conventional rotary joints, a spring-loaded
  seal is used for keeping the gas medium or fluid
  from getting dispersed into the surroundings.
  Here, the use of the spring is to maintain the
  initial internal seating. The rotary joint is
  maintained pressure-sealed when it is in
  operation. To create the seal, a low-pressure or
  vacuum service is used on the spring force.

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• Conventional rotary unions are externally
  supported, or they are self-supported using an
  internal carbon guide. As far as the external
  support is concerned, it is given by mounting
  brackets or rods.
• The fundamental purpose of rotary joints is to
  transfer medium from stationary supply lines to
  rotating or moving machine parts.
• Not only that, but rotary unions can also be
  designed with several flow passages, and they can
  handle different media simultaneously. Whenever
  media is supposed to be transferred in rotating
  or swiveling machine parts, it comes out as the
  right solution.
• Balanced seal rotary unions are popularly used
  with fluid service (e.g., water, coolant, etc.).
  However, they can also be used with steam and
  other gases.

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• The technology relies on optimizing the spring
  pressure to create a positive seal within the
  rotary union. The operating pressure of the media
  has hardly any effect on the sealing load.
  Balanced seals are typically flat face seals and
  in the rotary unions ball bearings are used for
  support. The seals are the main wearing
  components of a rotary joint and rotary union.
  When they are in operation, they experience
  internal loading forces from fluid pressure and
  friction from contacts between the faces of the
  sealing. When a seal fails, the media comes out.
  The efficiency of the entire heating or cooling
  process is adversely affected. Therefore, regular
  maintenance is important. It keeps the system in
  good health.

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VISIT www.rotaryunions.in Phone No 91 97122
71892 Email info_at_rotoflow.co.in Address
2794/23-1, Survey No. 264/4, B/H. Diomand Steel,
Pirojpura Road, Chhapi, Ta. Vadgam, Dist.
Banaskantha, Gujartat-385210, India.