Flange stud bolts, nuts, washers and custom fasteners for refineries, chemical plants and turnarounds along the Gulf Coast, machined in Humble, Texas.
Refinery and chemical-plant bolting sees heat, pressure and corrosive media, often all at once. Patriot Bolt machines fasteners to your drawing or specification and matches the nut and washer grade to the bolt so the whole joint is right.
We work in the alloy steels used for most flange bolting, the stainless grades used for corrosive service, and the nickel alloys and superalloys used where nothing else will last. Tell us the service temperature, pressure class and media and we will recommend a material.
- Common specsA193 · A194 · A320
- Hot serviceA193 B16
- Corrosive mediaB8M · Alloy 20 · C-276
- CoatingsPTFE
- Support24/7
What we make for petrochemical and refining
Stud Bolts
Full-thread, tap-end and double-end studs.
PB-02Nuts
Heavy hex and specialty nuts, graded to match.
PB-03Washers
Washers matched to the bolt and nut grade.
PB-04Heavy Hex Bolts
Coarse and fine thread, alloy to nickel.
PB-05Custom & Specialty Fasteners
One-off specials to production runs, to print.
PB-06FSI Replacement Parts
Replacement parts for FSI filter housings.
For the rest of the joint, Patriot Group company Protek Sealing supplies gaskets and sealing products.
Common grades we machine
| MATERIAL | WHY IT IS USED |
|---|---|
| ASTM A193 B7 | The workhorse for refining and petrochemical flange bolting, with A194 2H nuts. |
| ASTM A193 B16 | Cr-Mo-V alloy that keeps its strength at higher temperatures than B7. |
| 316 / 316L (B8M) | Molybdenum-bearing stainless for chlorides and chemical processing. |
| Alloy 20 | Austenitic alloy for acid and chemical service. |
| Hastelloy C-276 / C-22 | Nickel alloys for highly corrosive chemical environments. |
| Incoloy 825 | Nickel-iron-chromium alloy for acid and chloride service. |
See all 30+ grades in the Fastener Materials Matrix. Not sure which fits? Send the service temperature, pressure, media and any customer specification and we will recommend one.
Built to spec. Made in Texas.
Common questions
Which stud bolt material is best for high-temperature flanges?
A193 B16 retains strength at higher temperatures than B7 and is common for hot flange bolting. Send us the service temperature and pressure class and we will confirm the right grade and nut.
Do you supply matching nuts and washers?
Yes. We match A194 nut grades and washers to the bolt material so the joint is specified correctly.
Do you offer coated stud bolts?
Yes. PTFE fluoropolymer and other coatings are available. See our fastener coatings page for options.
Send us the print.
Drawing, spec sheet, sample or part number. We will quote it fast.