Double End Studs
Manufactured in various lengths and diameters from #2 to 4" diameter.
Includes tap-end studs to AWEM, API 6A, and custom drawings. Stepped, waisted, and reduced-shank geometries machined to order.
Specifications & technical data.
Double-end studs to ASME B18.31.2 — threaded both ends with an unthreaded body between, full-body or reduced-body, in every bolting grade we machine.
Download our double-end stud dimensioning table (PDF)
| Nominal Size | B min — Nut-End Minimum Full Thread Length | U max — Chamfered Thread Distance | |||||
|---|---|---|---|---|---|---|---|
| L < 10 | 10 ≤ L ≤ 16 | L > 16 | UNC | UNF | 8UN | ||
| 1/4" | 0.2500 | 0.750 | 1.000 | 1.500 | 0.100 | 0.071 | … |
| 5/16" | 0.3125 | 0.875 | 1.125 | 1.625 | 0.111 | 0.083 | … |
| 3/8" | 0.3750 | 1.000 | 1.250 | 1.750 | 0.125 | 0.083 | … |
| 7/16" | 0.4375 | 1.125 | 1.375 | 1.875 | 0.143 | 0.100 | … |
| 1/2" | 0.5000 | 1.250 | 1.500 | 2.000 | 0.154 | 0.100 | … |
| 9/16" | 0.5625 | 1.375 | 1.625 | 2.125 | 0.167 | 0.111 | … |
| 5/8" | 0.6250 | 1.500 | 1.750 | 2.250 | 0.182 | 0.111 | … |
| 3/4" | 0.7500 | 1.750 | 2.000 | 2.500 | 0.200 | 0.125 | … |
| 7/8" | 0.8750 | 2.000 | 2.250 | 2.750 | 0.222 | 0.143 | … |
| 1" | 1.0000 | 2.250 | 2.500 | 3.000 | 0.250 | 0.167 | … |
| 1-1/8" | 1.1250 | 2.500 | 2.750 | 3.250 | 0.286 | 0.167 | 0.250 |
| 1-1/4" | 1.2500 | 2.750 | 3.000 | 3.500 | 0.286 | 0.167 | 0.250 |
| 1-3/8" | 1.3750 | 3.000 | 3.250 | 3.750 | 0.333 | 0.167 | 0.250 |
| 1-1/2" | 1.5000 | 3.250 | 3.500 | 4.000 | 0.333 | 0.167 | 0.250 |
| 1-5/8" | 1.6250 | 3.500 | 3.750 | 4.250 | … | … | 0.250 |
| 1-3/4" | 1.7500 | 3.750 | 4.000 | 4.500 | 0.400 | … | 0.250 |
| 1-7/8" | 1.8750 | 4.000 | 4.250 | 4.750 | … | … | 0.250 |
| 2" | 2.0000 | 4.250 | 4.500 | 5.000 | 0.444 | … | 0.250 |
| 2-1/4" | 2.2500 | 4.750 | 5.000 | 5.500 | 0.444 | … | 0.250 |
| 2-1/2" | 2.5000 | 5.250 | 5.500 | 6.000 | 0.500 | … | 0.250 |
| 2-3/4" | 2.7500 | 5.750 | 6.000 | 6.500 | 0.500 | … | 0.250 |
| 3" | 3.0000 | … | 6.500 | 7.000 | 0.500 | … | 0.250 |
| 3-1/4" | 3.2500 | … | 7.000 | 7.500 | 0.500 | … | 0.250 |
| 3-1/2" | 3.5000 | … | 7.500 | 8.000 | 0.500 | … | 0.250 |
| 3-3/4" | 3.7500 | … | 8.000 | 8.500 | 0.500 | … | 0.250 |
| 4" | 4.0000 | … | 8.500 | 9.000 | 0.500 | … | 0.250 |
All dimensions in inches, per ASME B18.31.2-2014. LT = nominal stud length; U max = 2P where P is the thread pitch. Full-body and reduced-body diameters per the standard — details from our estimating team.
Standards.
What are double-end studs?
A double-end stud is threaded at both ends with a plain body between — one end makes up into equipment or a nut, the other carries the working nut. Full-body studs keep the shank at thread diameter; reduced-body studs turn it down near pitch diameter, which evens out stress and helps in fatigue service.
- Threaded both ends, plain center body
- Full-body or reduced-body per B18.31.2
- Any length, machined in-house
- B7, L7, B16, stainless and exotics
Double-end vs. tap-end studs
A double-end stud has equal-purpose ends for nut assembly both sides. A tap-end stud has a dedicated tap end — Class 5 interference thread — that screws permanently into a tapped hole, with the nut end doing the clamping. Machinery drawings usually say which; if yours doesn't, we can tell from the joint.
Other names
- Pad studs
- Double-ended studs
- Equipment studs
- Machinery studs
Tips for purchasing
- Specify body style — full or reduced — along with diameter, thread and length.
- Nut-end thread length follows the table; special lengths to order.
- Pair with heavy hex nuts certified together.
- MTRs and traceability come standard.
Materials.
Representative capabilities — every item is manufactured or certified to your specification. Confirm requirements with our estimating team.
