Weld Bung
-4AN 304 STAINLESS AN WELD BUNG
Weld-in AN weld bungs for -3AN to -16AN. 304 stainless, 4130 chromoly, and mild steel options.
SKU: ANWB-4-SS
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Technical Specifications
| Thread | 37° JIC / AN flare |
|---|---|
| Material | 304 Stainless or 4130 Chromoly |
| Weld Base | 0.375″ OD flange |
| Finish | Machined, clean |
| Compatible Fittings | All standard AN hose ends |
| Sizes | -3AN through -16AN |
Frequently Asked Questions
Can AN weld bungs be welded to stainless steel tanks?
Yes. The 304 stainless bungs weld to 304/316 stainless with ER308L filler. TIG is strongly preferred. Preheat is not required for stainless at this section size. Back-purge the inside of the tank to prevent oxidation at the root pass.
What is -6AN in mm?
-6AN refers to a tube OD of 6/16 inch (9.525 mm). The thread is 9/16-18 UNF with a 37° JIC sealing flare. AN sizes -3 through -20 follow the same formula: AN size × 1/16 inch = tube OD.
Stainless vs chromoly weld bungs — which for a fuel cell?
Use 304 stainless bungs for stainless or aluminum fuel cells running gasoline, E85, or methanol — stainless resists fuel corrosion best. Use chromoly bungs when welding to a chromoly or mild steel fuel cell, as they weld with standard ER70S-6 and require no stainless filler.