QSP AN Weld-On Fittings & Bungs

QSP’s weld-on range covers the threaded ports you weld into a tank, sump, pipe or radiator. Welding nuts take a threaded fitting and come in AN sizes from AN3 to AN16 and in metric threads from M10 × 1.0 to M22 × 1.5. Welding props give a male AN end, from AN4 to AN20, or a female NPT port from 1/8 to 3/4 inch.

Almost every size is offered in aluminium and in steel. Match the material to the part you are welding into: aluminium for alloy tanks, radiators and swirl pots, steel for steel tanks and exhaust work. QSP lists the AN and NPT parts for fuel and oil lines.

Two special groups complete the page. Lambda weld nuts in M18 × 1.5, in steel or stainless steel, provide a port for an oxygen sensor in the exhaust. Aluminium weld necks from 32 to 50 mm, radiator necks among them, give a filler or hose neck, and matching O-rings are sold separately for the 38, 40 and 50 mm necks.

Plan the port position before welding, leaving room for the hose end and a spanner, and pressure-test a fuel or oil tank after any welding.