Polypropylene Electrofusion and Butt Welding

Polypropylene electrofusion and butt weld fittings provide the most reliable and technically advanced methods of joining polypropylene (PP) pipe systems, delivering exceptionally strong, leak-free joints for demanding industrial and commercial applications. Designed for use in high-temperature and chemically aggressive environments, electrofusion and butt weld fittings are widely used across process industries where safety, reliability, and chemical resistance are critical.

At Pipestock, we offer a comprehensive range of PP electrofusion and butt weld fittings engineered to deliver consistent performance in harsh operating conditions, including chemical processing, water treatment, laboratory systems, and industrial fluid handling.

Electrofusion fittings are specialised polypropylene fittings with integrated electric heating coils embedded within the fitting body. When a controlled voltage is applied using an electrofusion control unit, the coils heat up, melting both the internal surface of the fitting and the external surface of the pipe. This process fuses the components together, creating a homogeneous welded joint that is as strong as the pipe itself.

Compared to traditional mechanical or solvent-based joining methods, electrofusion welding offers superior joint integrity, reduced risk of leaks, and consistent repeatable results.

• Material: Polypropylene homopolymer or polypropylene random copolymer (PP-H and PP-R)
• Colour: Beige grey (RAL 7032)
• Jointing Method: Electrofusion welding
• Approvals: Approved for water use only
• Operating Temperature Range: Typically -20°C to 110°C (short-term up to 130°C)
• Standards:
  • DIN 16962 Parts 5/6/7/8/9/12
  • ISO 7279:1984
  • ISO 15494:2003 Type B

• Design: Profiled fitting body to distribute stress and reduce joint fatigue
• Performance: Produces a strong, reliable, homogeneous welded joint

These fittings are manufactured from high heat-stabilised PP-H, providing excellent impact resistance at low temperatures and strong chemical resistance across a wide range of industrial fluids.

Alongside electrofusion, butt fusion welding is one of the most widely used and trusted methods for joining polypropylene (PP) pipework. Butt fusion creates a permanent, fully welded joint by heating and fusing the plain ends of pipes and fittings together under controlled pressure.

Where electrofusion is often favoured for site work, repairs, and confined installations, butt fusion is typically used for larger diameter pipe systems, long straight runs, and factory or workshop fabrication.

Butt fusion is a thermal welding process where the square-cut ends of two polypropylene components are heated against a temperature-controlled heater plate. Once the material reaches its molten state, the heater plate is removed and the components are pressed together under precise alignment and pressure. As the joint cools, the molten material solidifies into a single, continuous piece of polypropylene.

The result is a homogeneous joint with no seals, gaskets, or mechanical fasteners, providing excellent long-term reliability.

• Extremely strong joints - often matching or exceeding the strength of the pipe
• No additional fittings required for straight joints
• Excellent chemical and temperature resistance
• No leak paths created by seals or threads
• Cost-effective for larger systems and long pipe runs
• Ideal for prefabrication and modular pipe assemblies

Pipestock offers a broad selection of electrofusion fittings to suit complex polypropylene pipe systems, including:

• Electrofusion Sockets
  • Straight couplers designed to join two lengths of polypropylene pipe with a fully fused joint
• Electrofusion Elbows (45° and 90°)
  • Used to change the direction of flow in a pipeline while maintaining a fully welded joint, available in multiple pressure ratings
• Electrofusion Tees
  • Standard and reducing tees for branching pipelines, allowing for complex system layouts and controlled flow distribution
• Electrofusion Stub Flanges
  • Used in conjunction with backing rings and flanges to connect polypropylene systems to valves, pumps, and other flanged equipment
• Electrofusion End Caps
  • Used to terminate polypropylene pipe systems with a fully fused, pressure-rated closure.
• Electrofusion Reducing Sockets and Tees
  • Designed to transition between different pipe diameters while maintaining electrofusion joint integrity.

While straight pipe-to-pipe joints require no fittings, butt fusion systems rely on a range of plain-ended polypropylene fittings to create directional changes, branches, and equipment connections. 

Butt fusion fittings include (in 6 bar and 10 bar variations):

• Butt Fusion Elbows (45° and 90°)
  • Used to change the direction of flow while maintaining a fully welded joint and smooth bore
• Butt Fusion Tees
  • Available in equal configurations to branch pipelines or split flow paths
• Butt Fusion Reducers
  • Allow transitions between different pipe diameters while maintaining system integrity
• Butt Fusion Stub Flanges
  • Used with backing rings to connect polypropylene pipework to flanged valves, pumps, and other equipment

Both butt fusion and electrofusion are proven joining techniques for polypropylene pipe systems. The correct choice depends on pipe size, site conditions, system layout, and installation requirements.

At Pipestock, we supply polypropylene pipes and fittings suitable for both fusion methods, allowing you to design flexible, durable, and long-lasting pipe systems for even the most demanding applications.