TYPES OF PIPE JOINTS IN PLUMBING

• Pipe joints in water supply

  Major components of plumbing system provided to connect multiple pipes
• Threaded joint


  • Pipes are connected by screwing with the help of threads provided for each pipe
  • One pipe having internal threads and the other one having threads externally
  • Preferable for low temperature areas and low pressure flows
  • Installation is easy but good maintenance required
• Brazed joint


  • Jointing pipes using molten filler material at above 840°C
  • Filler material majorly consists of tin which has great affinity towards copper
  • Mechanical strength is low compared to other joints
  • Suitable in moderate range of temperature areas
• Soldered joint


  • Similar to brazing but the filler metal melts at below 840°C
  • Flux called paste is applied to pipes and fittings to prevent them from oxidation from flame
  • Suitable for low temperature areas
  • Low mechanical strength compared to brazed joints
• Butt welded joint


  • When the pipes are of same diameter
  • Provides good strength for the joint and can resist high pressure due to smooth and continuous surface inside the joint
• Socket welded joint


  • Used wherever there is a high chance of leakage in joints
  • Pipes are connected by putting one into the other and welded around the joint
  • Suitable for pipes having different diameters
• Flanged joint


  • Used for high pressure flows and for large diameter pipes
  • Two flange components are connected by bolts at the pipe joint to prevent leakage
  • Generally made of cast iron, steel etc.
  • Have good strength and do not fail against high pressure
  • Bolts may fail under creep at high temperatures
• Compression joint


  • When the pipes have plain ends, they are joined by installing some fittings at their ends
  • Can connect pipes of different materials and different sizes
  • Fittings should be properly fitted to resist high pressure, otherwise they may fail and cause leakage
• Grooved joint


  • Pipe ends consist of grooved edges which are connected by elastomer seal and ductile iron made grooved couplings
  • Easy to install and economical
  • Provide good resistance against pressure and allow moderate axial movement due to thermal expansion
  • Not suitable for high temperature areas as elastomer seal may lose its strength