Double-End Stud
Studs & Rods · double end stud · tap end stud · unequal thread stud
Definition: A double-end stud has threads on both ends — often of different lengths — with a plain center, threaded permanently into one part and nutted on the other.
Anatomy
■ Head■ Shank■ Threads■ Point
Governing standards: ASME B18.31.2 · ASTM A193
Common Sizes
| Inch | Metric | Head width | Head height |
|---|---|---|---|
| 1/2-13 | M12 | — | 3–12 long |
| 5/8-11 | M16 | — | 4–16 long |
| 3/4-10 | M20 | — | 5–20 long |
Representative sizes. Full dimensional data lives in the standards listed below.
Grades & Strength
| Grade | Material | Tensile (psi) | Marking |
|---|---|---|---|
| B7 | Cr-Mo alloy steel, Q&T | 125,000 | B7 |
| B8 | 304 stainless | 75,000 | B8 |
Materials
- B7 alloy steel
- B8 stainless steel
Pros & Cons
Pros
- The tapped part is not worn by repeated use
- Precise stud tension
- Easy replacement of worn threads
Cons
- Must be set to the correct engagement
- Two thread forms to specify
- Stud can turn if not seated firmly
Typical Uses
- Engine blocks and pump housings
- Valve bodies
- Piping flanges
- Repeated disassembly joints
Alternatives & Related
- Threaded Rod — Continuous thread for general use
- Stud Bolt — Fully threaded flange fastener
Where to Buy
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FAQ
Double-end stud vs stud bolt?
A double-end stud has a plain center and different thread lengths on each end; a stud bolt is fully threaded along its length for flanged joints.
Which end goes into the tapped hole?
The short tap end threads into the part; the longer nut end receives the nut. Check the spec for the required engagement.