Steel Fittings

Steel Pipe Fittings for Australian Plumbing and Industrial Pipework

Steel pipe fittings are the threaded elbows, tees, couplings, reducers, and adapters that connect steel pipe runs in plumbing, hydraulic, pneumatic, and industrial process pipework. For Australian plumbers, fitters, and pipework contractors, the right fitting matched to thread standard, pressure rating, and service environment is essential. Wrong fitting selection causes leaks, code violations, and premature service failures. AIMS Industrial supplies steel pipe fittings across the materials, finishes, and thread standards Australian trade and industrial customers actually use.

The fitting types we stock

• Elbows (90° and 45°) — for direction changes in pipe runs
• Tees — for branching from a main pipe run
• Couplings — for joining two pipes of the same size
• Reducers and reducing couplings — for transitioning between pipe sizes
• Caps and plugs — for sealing pipe ends
• Crosses — for four-way junctions
• Bushes — for reducing fitting size in tapped holes
• Hex nipples and barrel nipples — for connecting fittings end-to-end
• Unions — for connections that need to be disconnectable for service
• Flanged fittings — for bolt-flanged connections in larger pipework

Materials and finishes

• Galvanised steel (malleable iron) — the everyday standard for general plumbing and water service
• Black steel (malleable iron) — for gas service, fire main, and applications where galvanising isn't required
• Stainless steel 316 — for corrosive, marine, and food-grade applications
• Brass — for instrumentation, decorative, and specific industrial applications
• Forged carbon steel — for higher-pressure industrial pipework

Thread standards

• BSPT (British Standard Pipe Taper) — taper thread that seals as it tightens; the most common Australian pipe thread
• NPT (American National Pipe Taper) — US-spec taper thread, found in imported equipment and US-standard pipework
• BSPP (British Standard Pipe Parallel, also called G-thread) — parallel thread that seals with O-rings or sealing washers

BSPT, NPT, and BSPP are not interchangeable — confirm the standard before sourcing. Mixing thread standards causes leaks under pressure regardless of how tight the joint is made.

Sizing

Steel pipe fittings are sized by nominal pipe size (NPS) — a 1/2 inch fitting fits 1/2 inch nominal pipe (which has an actual outer diameter of about 21mm on the pipe itself). Common sizes include 1/8, 1/4, 3/8, 1/2, 3/4, 1 inch, 1-1/4, 1-1/2, 2 inch, with larger sizes for industrial and infrastructure work.

Pressure ratings

Steel pipe fittings are rated by pressure class. Common ratings include 150 PSI (1000 kPa) for general service galvanised malleable iron, with higher ratings for forged steel fittings used in higher-pressure applications. Confirm the fitting pressure rating against the system service pressure with appropriate safety factor.

Where steel pipe fittings earn their place

• Plumbing — water service — galvanised fittings on water supply pipework
• Gas service — black malleable iron fittings on gas distribution (codes specify materials and ratings)
• Hydraulic and pneumatic systems — steel fittings in industrial fluid power applications
• Compressed air distribution — galvanised or black fittings in workshop air systems
• Industrial process pipework — steel fittings in process water, steam, and specific chemical service
• Fire main and sprinkler systems — black or galvanised fittings to AS 2118 specification

Sealants and assembly

Threaded steel pipe fittings require thread sealant for leak-tight assembly. Common sealants include PTFE thread tape (the everyday plumbing standard), pipe joint compound (paste sealant), and anaerobic thread sealants (Loctite 567 or 577 for permanent industrial joints). Match the sealant to the service — see our pipe sealants range. Don't over-tighten threaded fittings — that strips threads, distorts the fitting, and creates more leak paths than it seals.

Brands and sourcing at AIMS

Steel pipe fittings are stocked from quality manufacturers covering galvanised malleable iron, black malleable iron, and stainless steel ranges. For specialty fittings, large sizes, or high-pressure-rated forged fittings, sourcing through our distribution channels covers most options.

Companion ranges at AIMS

Steel pipe fittings sit alongside our broader pipework range — see pipes, tubes and fittings, pipe sealants, pipe threading systems, and sanitary tube fittings for the related products.

Need help speccing steel pipe fittings for plumbing, gas, or industrial service? contact our team — we'll match by thread standard, material, and pressure rating.