Patriot Bolt makes double end studs: studs threaded on both ends with an unthreaded body in the middle. They clamp two parts together with a nut on each end, and the plain body gives a close, strong fit through the bolt holes.
We make double end studs in Humble, Texas, to ASME B18.31.2 or to your drawing, in carbon, alloy, stainless and nickel alloy grades. We supply the matching heavy hex nuts, and every order ships with mill test reports traceable to the heat.
Double End Studs at a Glance
- Type
- Threaded both ends, unthreaded body
- Standard
- ASME B18.31.2 (clamping type) or your drawing
- Thread ends
- Equal or unequal thread lengths, UNC, UNF or 8UN
- Grades
- A193 B7, B7M, B16, A320 L7, B5, stainless and nickel alloys such as Inconel 625 and Inconel 718
- Documents
- Mill test reports traceable to the heat
How Double End Studs Work
A double end stud has a thread on each end and a plain body between them. ASME B18.31.2 describes the clamping type as a stud with the same thread length and configuration on both ends, used with a nut on each end to clamp two parts together.
The unthreaded body is full diameter, so it fits the bolt holes more closely than threads do and is stronger in shear and bending than a threaded section of the same size. Double end studs are used on valves, pumps, compressors, flanged equipment and machinery where the bolted parts need to stay aligned.
Ordering Details
To quote double end studs, tell us:
- Diameter and thread, for example 7/8-9 UNC or 1-1/8-8 UN.
- Thread length on each end. Tell us if the two ends are equal or different.
- Overall length, measured end to end.
- End finish: chamfered, rounded or as shown on your drawing.
- Grade, coating and quantity.
If you send a drawing, we make the studs to it.
Grades
We make double end studs in the stud grades we already make, including A193 B7, B7M, B16, A320 L7, B5, stainless and nickel alloys such as Inconel 625 and Inconel 718. Compare grades in our Fastener Materials Matrix, and ask about coatings for corrosion protection.
Double End vs Full Thread Studs
A fully threaded stud is threaded from end to end, so one stud can suit many grip lengths and is the usual choice for pipe flange bolting. A double end stud has threads only where the nuts go. Use it when you want the plain body inside the joint for fit and strength, or when your drawing calls for set thread lengths.
Double End Studs FAQ
What is a double end stud?
A double end stud is a headless fastener threaded on both ends with an unthreaded body in the middle. It clamps two parts together with a nut on each end.
What standard covers double end studs?
ASME B18.31.2 covers inch double end studs, including the clamping type with identical ends and the tap end type. Metric double end studs are covered by ASME B18.31.1M.
Can the two thread lengths be different?
Yes. Equal ends are most common for clamping studs, but we make unequal thread lengths to your drawing. If one end goes into a tapped hole, see our tap end studs.
Do you supply the nuts?
Yes. We make and supply matching heavy hex nuts in the grade that suits your studs.
Request a Quote
Send us the diameter, thread, thread lengths, overall length, grade and quantity, or upload your drawing. Our team will confirm the details and lead time. Call (281) 581-0176 or request a quote.
Related: All stud bolts · Tap end studs · Heavy hex nuts · Stud bolt dimensions and tolerances