This is a list of various tank or bulkhead fittings that we offer and the hole sizes that they require to install them into a tank or container.
PVC and PP Bulkhead Fittings
| | Part Numbers |
| Hole Size | FNPT | PVC/Neoprene | PP/Neoprene | PVC/Viton | PP/Viton |
| 1-1/8" | 1/4" | 16401 | 16421 | 16641 | 16657 |
| 1-1/8" | 3/8" | 16402 | 16422 | 16642 | 16658 |
| 1-1/8" | 1/2" | 16403 | 16423 | 16643 | 16659 |
| 1-3/8" | 3/4" | 16404 | 16424 | 16644 | 16660 |
| 1-3/4" | 1" | 16405 | 16425 | 16645 | 16661 |
| 2" | 1-1/4" | 16406 | 16426 | 16646 | 16662 |
| 2-1/4" | 1-1/2" | 16407 | 16427 | 16647 | 16663 |
| 2-7/8" | 2" | 16408 | 16428 | 16648 | 1666 |
Maximum wall thickness for above tank fittings: 1/4" – 1" sizes 1/4" wall thickness
1-1/4" – 2" sizes 3/8" wall thickness
PVC & Polypropylene Heavy Duty Tank Fittings
| | Part Numbers |
| Hole Size | FNPT X Socket | PVC/EPDM | PP/EPDM |
| 1-1/4" | 1/2" | 16448 | 16468 |
| 1-5/8" | 3/4" | 16449 | 16469 |
| 1-7/8" | 1" | 16450 | 16470 |
| 2-5/16" | 1-1/4" | 16444 | 16464 |
| 2-9/16" | 1-1/2" | 16445 | 16465 |
| 3-3/16" | 2" | 16446 | 16466 |
| Hole Size | FNPT X FNPT | Part Numbers |
| 1-1/4" | 1/2" | 16439 |
| 1-5/8" | 3/4" | 16440 |
| 1-7/8" | 1" | 16460 |
| 2-5/16" | 1-1/4" | 16539 |
| 2-9/16" | 1-1/2" | 16540 |
| 3-3/16" | 2" | 16544 |
Banjo® Polypropylene Bulkhead Tanks Fittings with EPDM Gaskets
| Hole Size | FNPT x FNPT | Part Numbers |
| 1-5/8" | 1/2" | 32182 |
| 1-5/8" | 3/4"
| 32183 |
| 2-1/4" | 1" | 32194 |
| 2-1/4" | 1-1/4" | 32195 |
| 3" | 1-1/4" | 32199 |
| 3" | 2" | 32200 |
| 3-1/4" | 2" | 32227 |
| 4-1/2" | 3" | 32228 |
| 5-3/4" | 4" | 32229 |
Heavy Duty Polypropylene Tank Fittings with EPDM Gaskets
| Hole Size | FNPT x FNPT | Part Numbers |
| 1-7/16" | 1/2" | 11800 |
| 1-5/8" | 3/4" | 11801 |
| 2-1/4" | 1" | 11802 |
| 2-1/4" | 1-1/4" | 11803 |
| 3" | 1-1/2" | 11804 |
| 3" | 2" | 11805 |
Hayward® BFA Series Industrial Bulkhead Fittings with EPDM Gaskets
| | Part Numbers | |
| Hole Size | FNPT x FNPT | PVC | PP | CPVC | Max. Wall thickness |
| 1.38" | 1/2" | 16625 | 16687 | 16548 | 2.08" |
| 1.63" | 3/4" | 16626 | 16688 | 16556 | 2.08" |
| 1.88" | 1" | 16635 | 16689 | 16560 | 2.08" |
| 2.65" | 1-1/4" | 16636 | 16690 | 16576 | 2.00" |
| 2.65" | 1-1/2" | 16637 | 16691 | - | 2.00" |
| 3.25" | 2" | 16638 | 16692 | 16577 | 2.00" |
| 4.50" | 3" | 16639 | 16693 | 16578 | 2.12" |
| 5.75" | 4" | 16640 | 16694 | 16579 | 2.45" |
This is a good choice for thick walled tanks. Minimum Diameter of Tanks for Hayward® BFA Bulkhead Fitting Installation
| Bulkhead Size | Minimum Rigid Tank ID | Minimum Flexible Tank ID |
| 1/2" | 7.25" | 6.50" |
| 3/4" | 10.00" | 9.25" |
| 1" | 11.75" | 10.70" |
| 1-1/4" | 16.25" | 12.19" |
| 1-1/2" | 16.25" | 12.19" |
| 2" | 25.75" | 19.38" |
| 3" | 30.00" | 25.25" |
| 4" | 60.00" | 55.00" |
Hayward® BFAS Series Industrial Bulkhead Fittings
| | Part Numbers |
| Hole Size | FNPT x FNPT - PVC & PP
FNPT x Socket - CPVC | PVC/FPM | PVC/EPDM | PP/FPM | PP/EPDM | CPVC/EPDM |
| 1.38" | 1/2" | 16685 | 16705 | 16711 | 16723 | 16729 |
| 1.63" | 3/4" | 16686 | 16706 | 16712 | 16724 | 16730 |
| 1.88" | 1" | 16701 | 16707 | 16713 | 16725 | 16731 |
| 2.63" | 1-1/4" | 16702 | 16708 | 16714 | 16726 | 16732 |
| 2.63" | 1-1/2" | 16703 | 16709 | 16715 | 16727 | 16733 |
| 3.25" | 2" | 16704 | 16010 | 16716 | 16728 | 16734 |
Minimum Diameter of Tanks for Hayward® BFAS Bulkhead Fitting Installation
| Bulkhead Size | Minimum
Rigid Tank ID | Minimum
Flexible Tank ID | Max. Wall Thickness |
| 1/2" | 7.25" | 6.50" | 1.08" |
| 3/4" | 10.00" | 9.25" | 1.08" |
| 1" | 11.75" | 10.70" | 1.08" |
| 1-1/4" | 16.25" | 12.19" | 1.00" |
| 1-1/2" | 16.25" | 12.19" | 1.00" |
| 2" | 25.75" | 19.38" | 1.00" |
| 3" | 30.00" | 25.25" | 1.02" |
| 4" | 60.00" | 55.00" | 2.45" |
Spear’s PVC Tank Adapters
| | | | Part Numbers |
| Hole Size | FNPT x FNPT | Minimum Inside Radius | Maximum Wall Thickness | PVC/EPDM | PVC/Viton™ |
| 1-1/16" | 1/4" | 2.50" | .50" | 29215 | 29217 |
| 1-3/16" | 3/8" | 3.00" | .50" | 29216 | 29218 |
| 1-1/2" | 1/2" | 4.00" | .75" | 29187 | 29219 |
| 1-3/4" | 3/4" | 5.00" | .75" | 29188 | 29220 |
| 2" | 1" | 7.00" | .86" | 29189 | 29221 |
| 2-3/8" | 1-1/4 | 9.50" | .86" | 29190 | 29222 |
| 2-3/4" | 1-1/2" | 12.00" | .86" | 29191 | 29223 |
| 3-3/8" | 2" | 18.50" | 1.19" | 29192 | 29224 |
| 4-5/8" | 3" | 32.50" | 2.00" | 29193 | 29225 |
| 5-1/2" | 4" | 43.50" | 1.25" | 29194 | 29226 |
Spear's CPVC Tank Adapters
| Hole Size | FNPT x FNPT | Minimum Inside Radius | Maximum Wall Thickness | Part Numbers |
| 1-1/2" | 1/2" | 4.00" | .75" | 29195 |
| 1-3/4" | 3/4" | 5.00" | .75" | 29196 |
| 2" | 1" | 7.00" | .86" | 29197 |
| 2-3/4" | 1-1/2" | 12.00" | .86" | 29198 |
| 3-3/8" | 2" | 18.50" | 1.19" | 29199 |
| 4-5/8" | 3" | 32.50" | 2.00" | 29200 |
| 5-1/2" | 4" | 43.50" | 1.25" | 29214 |
Hayward® Self-Aligning PVC Tank Adapters
| Hole Size | FNPT | Part Number
PCV/EPDM | Minimum Rigid Tank Wall ID | Minimum Flexible Tank Wall ID |
| 3-1/4" | 1" | 16478 | 25.75" | 19.38" |
| 4-1/2" | 2" | 16479 | 42.50" | 36.25" |
| 5-3/4" | 3" | 16480 | 90.00" | 76.81" |
Polyethylene Bulkhead Fittings with EPDM Gaskets
| Hole Size | FNPT X FNPT | Part Numbers |
| 1-1/2" | 3/4" | 6260 |
| 2-3/8" | 1-1/2" | 6261 |
Den Hartog Tank Fittings
| Hole Size | FNPT | Part Number
PP/EPDM |
| 25/32" | 1/4" | 9744 (brass w/Viton™ o-ring) |
| 1-1/4" | 1/2" | 12787 |
| 1-3/8" | 1/2" | 9383 |
| 1-3/4" | 3/4" | 8554 |
| 1-3/4" | 1" | 8555 |
| 2-1/4" | 1-1/4" | 8556 |
| 3" | 1-1/2" | 8557 |
| 3" | 2" | 8558 |
| 3-1/4" | 2" | 11339 (heavy duty for tanks over 3,000 gallons) |
| 4-1/2" | 3" | 12528 |
Title: What size hole do I cut for your bulkhead fittings?
Description: Hole size charts for our bulkhead fittings
Published: 5/25/2012
Last Edited: 1/18/2023
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