Also available in 6061 aluminum: -6AN | -8AN | -10AN | -12AN | -16AN | -20AN | All AN weld bungs
Same size in: 304 stainless
6061 ALUMINUM MALE AN WELD BUNG: A WELD-IN 37° FLARE PORT FOR FUEL, OIL AND COOLANT LINES
This -4AN male weld bung is CNC machined from 6061-T6 aluminum with a 37° AN flare on the threaded end. Weld it to tanks, catch cans, radiators and surge tanks, and a -4AN female hose end or fitting threads straight onto it.
AN fittings seal metal to metal on the 37° flare, not on the threads, so no tape or thread sealant is needed. Keep the flare clean and undamaged and it will seal again every time the line comes off.
FEATURES
- 37° AN flare (SAE J514), 7/16-20 UNF thread
- CNC machined from 6061-T6 aluminum
- Pilot step on the weld end locates the bung in the hole
- Suitable for fuel systems, including E85
- Weld to aluminum only, with a matching aluminum filler
Full specifications (thread, diameters, height) are listed in the spec table at the bottom of this page.
WHAT CONNECTS TO IT
- Female AN hose ends and swivel fittings in the same dash size
- AN flare caps, for blanking the port off
45° SAE flare fittings look similar but will not seal on a 37° AN flare. Don't mix the two.
DASH SIZE REFERENCE
The dash number is the tube or hose OD in sixteenths of an inch.
| Size | Tube OD | Thread |
|---|---|---|
| -4AN (this bung) | 0.250" | 7/16-20 |
| -6AN | 0.375" | 9/16-18 |
| -8AN | 0.500" | 3/4-16 |
| -10AN | 0.625" | 7/8-14 |
| -12AN | 0.750" | 1-1/16-12 |
| -16AN | 1.000" | 1-5/16-12 |
| -20AN | 1.250" | 1-5/8-12 |
CUTTING THE HOLE
The weld end has a short pilot step that drops into the hole and locates the bung, with the shoulder sitting flat on the surface. Cut the hole to the body diameter in the spec table so the pilot fits snug and the bung sits square while you tack it.
WELDING TIPS
- Thread an AN cap or a spare female fitting on before welding. It protects the flare from spatter and helps the threads hold their shape.
- Tack it, then weld in short sections, alternating sides to keep heat even.
- Let the bung cool completely before removing the cap.
- Inspect the flare after welding and clean off any spatter before connecting a line.
SAFETY: Never weld, drill or grind on a tank that has held fuel.
Material tolerances: Diameters and heights in the spec table are nominal. Machined dimensions are subject to standard tolerances, so measure your parts before cutting holes. Nominal dimensions; material tolerances apply.
Shop all AN weld bungs and AN fittings and hose.
