AN Plumbing Weld Bungs and NPT Plumbing Weld Bungs
Weld Plumbing Bungs — AN & NPT Thread, Aluminum & Steel, Male & Female
Pro-Werks weld plumbing bungs are precision CNC machined from weldable 6061-T6 aluminum or mild steel — on the same machining centers responsible for so many of our precision parts. Available in both male and female versions, in AN and NPT thread sizes, to suit your specific plumbing configuration.
NPT vs. AN Threads — Which Do You Need?
NPT (National Pipe Taper) threads are tapered and seal by thread interference — commonly used with standard pipe fittings, sensors, and drain plugs. The go-to for oil pans, valve covers, and general plumbing applications.
AN (Army-Navy) threads are straight threads that seal with a flare or O-ring — the standard for high-performance racing fuel, oil, and dry sump plumbing. AN bungs accept standard AN hose end fittings (-4 through -16 AN).
Popular uses for both: Fuel tanks, dry sump tanks, valve cover venting, oil pans, coolant overflow tanks, custom fabricated reservoirs.
AN Thread Weld Bungs — Male & Female, Aluminum or Steel, -4 to -16 AN
Pro-Werks AN male weld bungs feature a contoured inlet for maximum flow and a stepped shoulder at the base that serves as a positioning locator — holds the bung in place while welding in a flat surface or tube end. Ample cross section in the weld land reduces warping during welding. Available in 6061-T6 aluminum or mild steel.
Male AN Weld Bungs — Aluminum or Steel:
- -4 AN — 3/4" diameter, also fits 3/4" OD × 0.058" wall tube
- -6 AN — 7/8" diameter, also fits 7/8" OD × 0.058" wall tube
- -8 AN — 1" diameter, also fits 1" OD × 0.058" wall tube
- -10 AN — 1-1/8" diameter, also fits 1-1/8" OD × 0.058" wall tube
- -12 AN — 1-3/8" diameter, also fits 1-3/8" OD × 0.058" wall tube
- -16 AN — 1-5/8" diameter, also fits 1-5/8" OD × 0.058" wall tube
Female AN Weld Bungs — Steel:
- -4 AN Female — 7/16-20 Thread, 3/4" OD
- -6 AN Female — 9/16-18 Thread, 7/8" OD
- -8 AN Female — 3/4-16 Thread, 1-1/8" OD
- -10 AN Female — 7/8-14 Thread, 1-1/4" OD
- -12 AN Female — 1-1/16-12 Thread, 1-1/2" OD
- -16 AN Female — 1-5/16-12 Thread, 1-3/4" OD
Pro-Werks AN Thread Weld Bung — 6061-T6 aluminum or mild steel, male & female, -4 to -16 AN
NPT Female Weld Bungs — Aluminum, Steel & Stainless, 1/16" to 3/4" NPT
Pro-Werks NPT female weld bungs simplify tank fabrication. Precision CNC machined in 6061-T6 aluminum, mild steel, or stainless steel (1/8" NPT only). Tapered NPT threads seal by thread interference — ideal for sensors, drain plugs, and standard pipe fittings.
- 1/16 NPT Female — 5/8" OD — Aluminum & Steel
- 1/8 NPT Female — 3/4" OD — Aluminum, Steel & Stainless Steel
- 1/4 NPT Female — 7/8" OD — Aluminum & Steel
- 3/8 NPT Female — 7/8" OD (Aluminum) / 1" OD (Steel)
- 1/2 NPT Female — 1-3/16" OD (Aluminum) / 1-1/4" OD (Steel)
- 3/4 NPT Female — 1-3/8" OD — Aluminum
Pro-Werks NPT Female Weld Bung — 6061-T6 aluminum, mild steel, or stainless (1/8" NPT), 1/16" to 3/4" NPT
Complete Your Plumbing Project
Weld plumbing bungs pair perfectly with these related components from The Chassis Shop:
- Fill Caps & Bungs — Pro-Werks billet aluminum Easy Turn fill caps and weld-in mounting bungs for fuel cells and custom tanks
- Bar, Bottle & Universal Mounts — tank and bottle mounting solutions for your chassis build
- Tubing & Custom Bends — 4130N chromoly tubing that AN male bungs also fit directly into by OD
Note: Welding should always be performed by a qualified welder.
Proudly Made in the USA.
