Recommend Products
Name: Fujian Monel 400 Double End Stud Material: Monel 400 Standard: ASME B18.2.1 Size: 5/16 to 4 inch Length: 30 to 1000 mm Class: 12.9 Feature: Resistant to hydrofluoric acidQS Fastener: Monel 400 Double End Stud
Name: Inconel 625 Double End Stud Material: Inconel 625 Standard: ASME B18.2.1 Size: 5/16 to 4 inch Length: 30 to 1000 mm Class: 12.9 Feature: High Yield Strength, Durable Strength and Corrosion ResistanceQS Fastener: Inconel 625 Double End Stud
Name: Xiamen Inconel 600 High Strength Fastener Material: Inconel 600 Standard: ASME Size: 5/16 to 4 inch Length: 30 to 1000 mm Class: 12.9 Feature: High Yield Strength, Durable Strength and Corrosion ResistanceQS Fastener: Inconel 600 High Strength Fastener
Name: Inconel 600 Stud Bolt Putian Material: Inconel 600 Standard: ASME B18.2.1 Size: 5/16 to 4 inch Length: 30 to 1000 mm Class: 12.9 Feature: High Yield Strength, Durable Strength and Corrosion ResistanceQS Fastener: Inconel 600 Stud Bolt
Nickel-based Alloy Double End Stud
QS Fastener: Nickel-based Alloy Double End Stud
Name: Nickel-based Alloy Double End Stud
Standard: ASME
Material: Nickel-based Alloy
Size: 3/4 inch
Lenght: 130 mm
Temperature: 650-700℃
Surface: Natural color
Standard: ASME
Material: Nickel-based Alloy
Size: 3/4 inch
Lenght: 130 mm
Temperature: 650-700℃
Surface: Natural color
Quantity
Special Alloy Double End Stud – manufactured to ASME standards, 3/4 inch diameter, 130 mm overall length, purpose-built to resist creep and stress-corrosion at 650–700 °C, supplied in the as-produced finish. It is the most reliable “high-temperature seat-belt” for flange joints in petrochemical plants, nuclear power stations and ultra-super-critical boilers.
How do nickel-alloy fasteners differ from common 304 or 316 stainless?
Place 304/316 stainless and nickel-base alloys (Inconel 625, 718, 825, etc.) on the same scale and the gap is “family sedan vs. space shuttle”. Below are five dimensions every engineer or buyer can grasp at a glance.
Place 304/316 stainless and nickel-base alloys (Inconel 625, 718, 825, etc.) on the same scale and the gap is “family sedan vs. space shuttle”. Below are five dimensions every engineer or buyer can grasp at a glance.
| Dimension | 304/316 stainless | Nickel-alloy fasteners | Why the nickel alloy is worth the money |
| ① Chemistry (it rules everything) | 18Cr-8Ni + trace Mo | 50–70 %Ni, 20 %Cr, 9 %Mo + Nb, Ti, Al | Nickel costs ~4× stainless; raw-material cost doubles immediately. |
| ② Temperature ceiling | 304 ≤ 550 °C; 316 ≤ 700 °C—oxidation starts and strength collapses | Inconel 625 still 210 MPa yield at 950 °C; 718 creep life ≥ 3 000 h at 650 °C | Ultra-super-critical turbines, aero-engines and reformer furnaces demand nickel; stainless fails within a month. |
| ③ Corrosion rank | 316 survives seawater and Cl⁻, but >50 °C in concentrated Cl₂, wet H₂S or sulphuric acid it pits | 625 corrodes <0.01 mm/a in 60 °C saturated Cl₂ + 1 000 ppm H₂S; 825 stays passive in 65 % boiling HNO₃ | Offshore riser bolts in 625 last 25 years maintenance-free; 316 seizes in six months—one shutdown costs USD 5 M. |
| ④ Strength-to-weight | 304 UTS 520 MPa, yield 210 MPa | 718 solution-aged: UTS 1 350 MPa, yield 1 100 MPa | Same preload permits one diameter smaller bolt, 30 % lighter flange, half the assembly man-hours. |
| ⑤ Ex-works price (Sept 2025 market) | M12×50 hex bolt 304 ≈ CNY 0.8 pc; 316 ≈ CNY 1.3 pc | Inconel 625 ≈ CNY 38–42 pc; 718 ≈ CNY 55–60 pc | Unit price ratio 40×, yet life-cycle cost only 1/10 that of 316—one offshore maintenance vessel trip costs CNY 0.8 M; avoiding a single visit pays back the difference. |
Real cases
1. 700 °C petrochemical reformer: 316 double-end studs crept and stretched in three months, flange leaked and caught fire; after switching to Nickel-based Alloy Double End Stud (Inconel 718) the unit has run six years without a shutdown.
1. 700 °C petrochemical reformer: 316 double-end studs crept and stretched in three months, flange leaked and caught fire; after switching to Nickel-based Alloy Double End Stud (Inconel 718) the unit has run six years without a shutdown.
2. Launch-pad LOX/kerosene turbopump: cycling from –183 °C to +450 °C—only Nickel-based Alloy Double End Stud (718 bolts) survive; 304 suffers outright low-temperature brittle fracture.
3. Nuclear-submarine reactor coolant pump: Nickel-based Alloy Double End Stud (alloy 825 bolts) in 320 °C, 3 % boric-acid loop for 30 years—zero stress-corrosion cracking; 316 showed SCC cracks in two years.
Take-away
304/316 is “economy-class body armour”; nickel alloy is “heavy armour plus nitro boost”. Under the triple extremes of temperature, corrosion and stress you are not paying for metal—you are buying the safety margin of “zero downtime”. Whenever the cost of failure exceeds the price of the bolt by fifty times, choosing Nickel-based Alloy Double End Stud means buying the most expensive…and simultaneously the cheapest option available.
304/316 is “economy-class body armour”; nickel alloy is “heavy armour plus nitro boost”. Under the triple extremes of temperature, corrosion and stress you are not paying for metal—you are buying the safety margin of “zero downtime”. Whenever the cost of failure exceeds the price of the bolt by fifty times, choosing Nickel-based Alloy Double End Stud means buying the most expensive…and simultaneously the cheapest option available.
Send Message
