Stud Bolts ASTM A193 B8 SS

Stud Bolts ASTM A193 B8 Class 1 — 304 Stainless Steel Stud Bolts | M12–M72

ASTM A193 B8 Class 1 stud bolts are manufactured from 304 (AISI 304/SS304) austenitic stainless steel, providing excellent corrosion resistance for flange connections in chemical processing, food & beverage, and pharmaceutical industries. These carbide-solution-treated stainless steel studs are paired with ASTM A194 Grade 8 stainless steel nuts for complete corrosion-resistant bolting assemblies.

Material & Specifications

Size Range	M12 to M72 / 1/2″ to 4″
Standard	ASTM A193 Grade B8 Class 1, ASME SA193 B8
Material	AISI 304 (UNS S30400) Austenitic Stainless Steel — Solution Annealed
Surface / Coating	Plain/Passivated (standard), PTFE coated (anti-galling)
Tensile Strength	≥ 515 MPa (75 ksi)
Yield Strength	≥ 205 MPa (30 ksi)

Surface Treatment & Zinc Coating Quality

At BoltNutsPlus, we understand that surface treatment is critical to fastener longevity and performance. Our products undergo rigorous coating processes to ensure maximum corrosion resistance and durability. We offer five premium coating options, each tested to international standards:

• Hot-Dip Galvanizing (HDG) — Thick zinc layer (50-120μm) providing superior long-term corrosion protection for outdoor, marine, and industrial environments. Compliant with ISO 1461 / ASTM A153 standards. Salt spray resistance: 500-1,000+ hours. Ideal for structural steel assemblies exposed to harsh weather.
• Electroplated Zinc Blue-White (Zn Blue/White) — Bright, clean silver-blue appearance with 5-15μm zinc layer. Cr3+ passivation technology, fully RoHS compliant. Ideal for indoor machinery, electronics, and general-purpose applications requiring aesthetic appeal and moderate corrosion resistance.
• Color Zinc / Yellow Zinc (Iridescent Passivation) — Multi-colored iridescent passivation film offering enhanced corrosion resistance (100-200 hours salt spray) with a distinctive golden finish. Widely preferred in automotive, agricultural equipment, and construction machinery sectors for its balanced protection and visual appeal.
• Dacromet Coating — Advanced water-based zinc-chromium coating technology with NO hydrogen embrittlement risk. Provides 1,000+ hours salt spray resistance, making it the preferred choice for high-strength fasteners in extreme environments. Environmentally friendly (no heavy metal discharge), RoHS/ELV compliant, ideal for automotive and wind energy applications.
• Multi-Element Alloy Co-Permeation — Zinc-aluminum-rare earth alloy layer offering 2-3x the corrosion resistance of traditional galvanizing. Features self-healing properties at scratch points, ensuring long-term protection even in damaged areas. Ideal for critical infrastructure, power transmission towers, coastal projects, and marine installations.

Key Features

• 304 stainless steel provides excellent corrosion resistance in chemical environments
• Carbide solution treatment (Class 1) for optimal intergranular corrosion resistance
• Non-magnetic austenitic structure ideal for food and pharmaceutical applications
• Paired with ASTM A194 Grade 8 matching stainless steel nuts
• PTFE coating option prevents galling during installation and removal
• Full material certification with chemistry and mechanical test reports

Applications

• Chemical processing plant flange connections
• Food & beverage industry sanitary piping systems
• Pharmaceutical processing equipment and piping
• Pulp & paper industry corrosive environment piping
• Marine and coastal infrastructure flange connections
• Any application requiring corrosion-resistant flange bolting

Why Choose BoltNutsPlus?

• ISO 9001:2015 Certified Manufacturing — consistent quality you can trust on every batch
• 15+ Years of Export Experience — serving 40+ countries across 6 continents
• Full Traceability — material certificates (EN 10204 3.1) and comprehensive test reports included
• Custom Packaging & OEM/ODM — your brand identity, your specifications, our precision manufacturing
• Third-Party SGS / Bureau Veritas Inspection Available upon request
• 24-Hour Quote Response — same-day reply for urgent requirements; standard 24-hour turnaround