PEX Fittings – The Connectors Joining Crosslinked Polyethylene Plumbing Systems

PEX Fittings – The Connectors Joining Crosslinked Polyethylene Plumbing Systems
An In-Depth Look at PEX Fitting Types, Properties, Installation, and Benefits

Crosslinked polyethylene (PEX) piping relies on the corresponding fittings to create fully functioning plumbing systems. This article explores PEX fittings, their capabilities, proper installation, and importance in residential and commercial PEX plumbing networks. IFAN factory with 30+ years of manufacturing experience supports color/size customization support free samples. Welcome to consult for catalog and free samples. This is our Facebook Website:

pex fittings

What are PEX Fittings?

PEX fittings are connectors used to join PEX pipes, change direction, branch off, alter sizes, and adapt to other components. They allow the assembly of full PEX piping systems from supply lines to fixture connections.

PEX fittings are made from PEX plastic to provide the ideal bonding properties when joining the tubing. They create secure, watertight seals for reliable performance.

Common PEX Fitting Types

PEX fittings are available in a wide range of standard configurations:

  • Elbows – 90° and 45° elbows change direction in runs.
  • Tees and crosses – Allow branching main PEX lines to feed additional lines.
  • Couplers and unions – Join two sections of PEX tubing.
  • Adapters – Connect to other fitting materials like metal or NPT threads.
  • Caps – Provide closed ends to PEX lines.
  • Outlet fittings – Connect PEX piping to fixtures and appliances.

PEX fitting shapes and sizes conform to industry standards for optimal PEX piping integration.

Key Properties of PEX Fittings

Quality PEX fittings share the beneficial properties of PEX that make it an exceptional plumbing material:

  • Flexibility – PEX fittings move with pipe expansion/contraction.
  • Corrosion resistance – Fittings withstand exposure to water.
  • Thermal resilience – Performance maintained through temperature extremes.
  • Chlorine resistance – NSF-rated for potable water systems.
  • High strength – Durable and robust for long service life.

Proper PEX fitting materials selection ensures optimal bonding and reliability. Approved PEX fittings maintain water purity.

PEX Fitting Connection Methods

There are several techniques for joining PEX fittings to PEX pipes:

  • Compression – Tightening a nut compresses a ring around the tubing.
  • Crimp – A crimping tool compresses metal bands around the tubing into a fitting.
  • Cold expansion – Expanding a fitting compresses the tubing against the fitting wall.
  • Push-to-connect – Inserting tubing into the fitting depresses a collet for grip.
  • Threaded – Male NPT threaded fittings screw into female adapters.

Each method forms strong, permanent joints. Push-to-connect and cold expansion allow quick connections without requiring tools.

Proper Support and Installation of PEX Fittings

PEX fitting systems require proper installation and support:

  • Hangers and clamps distribute weight and minimize stresses.
  • Proper routing allows access to fittings for repairs.
  • Manufacturer instructions prevent excessive forces.
  • Allowing pressure testing validates watertight joints.
  • Periodic inspection checks for damage or leaks.

Following codes and specifications preserves fitting integrity for decades. Careful workmanship enables full realization of PEX benefits.

Transition Fittings Enable Multi-Material Integration

While PEX systems use PEX fittings for most connections, transitions are needed to incorporate components of other materials:

  • PEX x NPT – Connect to threaded valves, pumps and equipment.
  • PEX x Copper – Common adapters to tie into existing copper plumbing.
  • PEX x PPR – Combine hot water PEX with PPR supply piping.
  • PEX x Metal – Transition between PEX and galvanized, black iron or stainless piping.

Having suitable transition PEX fittings avoids limiting PEX to only certain sections of plumbing. It simplifies integration.

Advantages of PEX vs. Metal Fittings

PEX fittings provide many benefits compared to traditional metal fittings:

  • Watertight seals without requiring soldering or threading.
  • Accommodates thermal expansion and contraction of PEX tubing.
  • Quick, flame-free installations.
  • Resists scale buildup and corrosion.
  • Allows convenient plumbing modifications with simple connections.
  • Long service life without leaks or flow restrictions.

PEX fittings outperform metals across critical factors for residential and commercial plumbing systems.

The Role of PEX Fittings in Plumbing Systems

PEX fittings serve indispensable functions enabling complete piping networks. Their ability to make watertight PEX connections, adapt components, and customize layouts determines system functionality.

Quality fittings properly selected and installed are integral to realizing the full advantages of crosslinked polyethylene plumbing. As PEX gains global use, so does the importance of the fittings joining it into reliable water delivery systems.


IFAN factory started in 1993. And IFAN has a workshop of 120000 square meters with 610 staff. IFAN can design and produce all plumbing pipe and fitting including PPR, PVC, CPVC PPSU HDPE PEXA PEXB PERT pipe and fitting, brass fitting, brass ball valve, heating system, gas system, sanitary faucets, and hose, In the past 30 years, IFAN has never forgotten his mission-To protect health and safety. And IFAN factory uses the best materials to produce high-quality pipe and fittings with an automatic production line and high-tech quality control machines. 



Table of Contents