In November, 2025, one of our regular clients inquired some stud bolts and nuts. This is exactly what we offered through the years as bolts and nuts are crucial accessories in oil and gas industries. We emailed our quotation based on the client’s description and showed some bolts inspections photos. Around 2 weeks later, we received purchase order from this Serbian client.
Goods List
| ITEM | DESCRIPTION | QTY | UNIT |
| 1 | Studbolt ASTM A193-B7 with 2 ASTM A194-2H Hvy. Hex Nuts, 1″x190mm, Xylan 1014 coated | 80 | SET |
| 2 | Studbolt ASTM A193-B7 with 2 ASTM A194-2H Hvy. Hex Nuts, 1-1/2″x270mm, Xylan 1014 coated | 20 | SET |
| 3 | Studbolt ASTM A193-B7 with 2 ASTM A194-2H Hvy. Hex Nuts, 2″x440mm, Xylan 1014 coated | 36 | SET |
| 4 | Studbolt ASTM A193-B7 with 2 ASTM A194-2H Hvy. Hex Nuts, 2″x485mm, Xylan 1014 coated | 80 | SET |
| 5 | Studbolt ASTM A193-B7 with 2 ASTM A194-2H Hvy. Hex Nuts, 2-1/2″x610mm, Xylan 1014 coated | 40 | SET |
| 6 | Studbolt ASTM A193-B7 with 2 ASTM A194-2H Hvy. Hex Nuts, 2-3/4″x675mm, Xylan 1014 coated | 98 | SET |
ASTM A193 B7 Stud Bolts
ASTM A193 B7 is a high-strength chromium-molybdenum steel grade designed for bolting, studs, and threaded fasteners in high-temperature and high-pressure service conditions. It undergoes quenching and tempering heat treatment to achieve optimal mechanical performance.
B7 Chemical Composition (percent)
| Element | Content Range |
| Carbon (C) | 0.38 – 0.48 |
| Manganese (Mn) | 0.75 – 1.00 |
| Phosphorus (P) | ≤ 0.035 |
| Sulfur (S) | ≤ 0.040 |
| Silicon (Si) | 0.15 – 0.35 |
| Chromium (Cr) | 0.80 – 1.10 |
| Molybdenum (Mo) | 0.15 – 0.25 |
B7 Mechanical Properties
- Tensile Strength: Minimum 125 ksi (862 MPa)
- Yield Strength (0.2% offset): Minimum 105 ksi (724 MPa)
- Elongation in 2 inches: Minimum 16%
- Reduction of Area: Minimum 50%
- Hardness: 321HBW/35HRC
ASTM A194 2H Nuts
ASTM A194 2H is a carbon steel grade exclusively for nuts, engineered to match the mechanical performance of ASTM A193 B7 bolts and studs—creating a compatible fastener assembly for industrial high-stress applications. It is also heat-treated (quenched and tempered) for enhanced strength and toughness.
2H Chemical Composition (percent)
| Element | Content Range |
| Carbon (C) | 0.40 min |
| Manganese (Mn) | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.040 |
| Sulfur (S) | ≤ 0.040 |
| Silicon (Si) | 0.15 – 0.35 |
2H Mechanical Properties
ASTM A194 2H nuts shall meet hardness requirements (248–327 BHN for sizes ≤1-1/2 inch; 212–327 BHN for sizes ＞1-1/2 inch) and proof load specifications per ASTM A194, ensuring thread strength matching ASTM A193 B7 bolts. Heat treatment (quenching and tempering) is mandatory for consistent performance in high-pressure applications.
Xylan 1014 Teflon Coating
Xylan 1014 is a high-performance fluoropolymer coating (PTFE/Teflon-based) formulated for industrial fasteners, combining low friction, extreme corrosion resistance, and chemical inertness. It is widely applied to ASTM A193 B7 bolts and ASTM A194 2H nuts to protect against rust, chemical attack, and galling during installation and service.
Goods Inspection
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We welcome inquiries or drawing from project developers, contractors and enterprise clients and will offer professional technical support and efficient manufacturing services.
Look forward to being your reliable partner.
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EMAIL: sales@zzsteels.com
TEL: +86 372 2155516
Mob: +86 18625862121