A193 B7 stud bolts
B7 studs and stud bolts manufactured to ASTM A193 and supplied with A194 2H heavy hex nuts, in diameters from 1/4 in. through 4 in.
B7 studs, defined by the order.
ASTM A193 Grade B7 is a widely specified alloy steel bolting grade for flanges, valves, pressure vessels and fittings in high-temperature or high-pressure service. It is a chromium-molybdenum steel, AISI 4140/4142, quenched and tempered. Cyclone manufactures and supplies B7 studs with two A194 2H heavy hex nuts, in plain and coated finishes.
- Plain, TFE blue and cadmium-plated finishes
- Diameters from 1/4 in. through 4 in.
- Length cut to your specification
- Thread series and class confirmed with your RFQ
Specify diameter, length, thread series and class, quantity, finish, required delivery, and documentation.
B7 stud bolt range
| Detail | Available range |
|---|---|
| Specification | ASTM A193 Grade B7 |
| Assembly | B7 stud with two A194 2H heavy hex nuts |
| Finishes | Plain, TFE blue, cadmium plated |
| Other finishes | Zinc, black oxide, hot-dip and mechanical galvanizing, Xylan®, Fluorokote #1® and the other finishes on the Cyclone line card |
| Diameter | 1/4" through 4" |
| Length | To the customer’s specification |
| Threads | As specified. 8 threads per inch (8UN) is the usual call-out above 1" |
What the specification requires.
These are the minimum mechanical properties ASTM A193 lists for Grade B7 across Cyclone’s diameter range. The current edition of the standard governs your order.
| Diameter | Tensile strength, min | Yield strength, min | Elongation, min | Reduction of area, min | Hardness, max |
|---|---|---|---|---|---|
| 2-1/2" and under | 125 ksi | 105 ksi | 16% | 50% | 321 HBW or 35 HRC |
| Over 2-1/2" through 4" | 115 ksi | 95 ksi | 16% | 50% | 321 HBW or 35 HRC |
Source: ASTM A193/A193M, Grade B7. Reference only.
Material
Chromium-molybdenum alloy steel, AISI 4140/4142, quenched and tempered.
Companion nuts
ASTM A194 Grade 2H heavy hex nuts are the standard pairing for B7 studs. Cyclone lists them plain, TFE blue and cadmium plated. See heavy hex nuts.
Thread series
Coarse thread (UNC) is standard through 1 in. Above 1 in., B7 studs for flange and pressure service are normally ordered with 8 threads per inch (8UN). State the series and class on your order.
Length
Flange stud length is conventionally measured first thread to first thread, without the points. Tell us which convention your drawing uses.
Documentation
List the material test reports, certificates of conformance and any additional testing the order requires. See inspection and release documentation.
Questions before you quote
Is a B7 stud the same as a B7 stud bolt?
Buyers use the two terms interchangeably. A stud bolt usually means a fully threaded stud supplied with two heavy hex nuts, which is how Cyclone lists its B7 assemblies.
Which nuts are used with A193 B7 studs?
ASTM A194 Grade 2H heavy hex nuts. Cyclone supplies them plain, TFE blue or cadmium plated to match the stud.
What sizes of B7 studs does Cyclone supply?
Diameters from 1/4 in. through 4 in., with length cut to your specification. Ask the team about availability for your exact size and quantity. This page is not a live inventory list.
Can B7 studs be supplied coated?
Yes. Cyclone lists B7 studs in plain, TFE blue (a blue PTFE coating) and cadmium-plated finishes. See coated and plated stud bolts.
Will Cyclone choose the bolting grade for my application?
No. Material selection belongs to the responsible engineer and the governing code. Cyclone manufactures and supplies to the specification on your order.