Amigo Impex is a Hastelloy fasteners manufacturer, stockist and exporter based in Mumbai, India, operating since 2013. Cutting, machining, threading, testing and packing are carried out in-house, allowing bolts, nuts, studs and washers to be supplied together with the required material documentation.
Hastelloy fasteners are corrosion-resistant bolting components machined from nickel-alloy bar supplied to ASTM B574 / ASME SB-574, covering the low-carbon nickel-molybdenum-chromium grade C276 (UNS N10276) and the low-carbon nickel-chromium-molybdenum grade C22 (UNS N06022). Molybdenum improves resistance to reducing acids and pitting, while chromium contributes to resistance in oxidising environments. These properties make Hastelloy fasteners suitable for applications involving hydrochloric acid, sulphuric acid, wet chlorine and chloride-containing media.
The standard range includes Hastelloy C276 in ready stock and Hastelloy C22 for production against order. In C276 (UNS N10276), bolts, screws and studs are supplied to ASTM F468 and nuts to ASTM F467, both of which list N10276 as a covered alloy. UNS N06022 is not a listed alloy in ASTM F468 or ASTM F467, so C22 fasteners are machined from certified ASTM B574 bar to the dimensional and property requirements agreed on the order. NACE MR0175 / ISO 15156 can be applied where material selection is required for sour-service environments.
Imperial sizes from 1/4 in to 1-1/2 in are supplied to ASTM F468 (bolts, screws, studs) and ASTM F467 (nuts). Metric sizes are supplied to ASTM F468 material and property requirements with dimensions to ISO 4014 (hex bolts), ISO 4017 (hex screws) and ISO 4032 (hex nuts). Smaller and larger sizes, from M1.2 and #00 up to M48 and 4 in, are machined to customer drawing from certified ASTM B574 material. Threads can be rolled or cut, and the range includes bolts, nuts, washers, screws, studs, threaded rods, U-bolts, anchor bolts and eye bolts. Supply covers pan-India from Mumbai, with exports to the USA, Gulf, Europe and Asia. Ready stock of approximately 60 to 70 tonnes supports urgent requirements, while made-to-order production generally requires around 30 days.
Grade, fastener type, diameter, thread form and required condition determine the specification for each Hastelloy fastener order. The table below summarises the standard supply range.
Several standards can apply to a Hastelloy fastener order. ASTM F468 and ASTM F467 cover the finished fasteners, ASTM B574 / ASME SB-574 covers the nickel alloy rod and bar used for machining, and dimensional standards define specific head, washer and thread configurations.
| Standard | Scope |
|---|---|
| ASTM F468 | Nonferrous bolts, hex cap screws, socket head cap screws and studs for general use |
| ASTM F467 | Nonferrous nuts |
| ASTM B574 / ASME SB-574 | Low-carbon nickel-molybdenum-chromium and nickel-chromium-molybdenum alloy rod and bar |
| NACE MR0175 / ISO 15156 | Materials for use in H₂S-containing environments in oil and gas production; sets environmental and hardness limits for qualified alloys |
| ISO 4762 (formerly DIN 912) | Socket head cap screw dimensions |
| ISO 4026 to 4029 (formerly DIN 913 to 916) | Set screw and grub screw dimensions |
| ISO 7089 / ISO 7090 (formerly DIN 125) | Flat washer dimensions |
The standard range includes Hastelloy Fasteners in C276 and C22 grades. C276 is a low-carbon nickel-molybdenum-chromium alloy, and C22 is a low-carbon nickel-chromium-molybdenum alloy. Their different chromium and molybdenum levels provide different levels of resistance in reducing and oxidising service.
Hastelloy C276 fasteners, identified as UNS N10276, provide strong resistance to a wide range of corrosive environments, including reducing acids, mixed acid streams, chloride-containing media and sour-service conditions. C276 fasteners are held in ready stock for common requirements.
Hastelloy C22 fasteners, identified as UNS N06022, have a higher chromium content than C276 and are particularly suitable for applications involving strongly oxidising media. They can be considered for service involving ferric and cupric chlorides, wet chlorine and other aggressive oxidising environments. C22 fasteners are machined to order.
Hastelloy fasteners are available across the same general size range for both C276 and C22, subject to grade, fastener type and production requirements. Sizes not held in ready stock can be machined from certified material to the required dimensions.
| Parameter | Range |
|---|---|
| Standard Bolt and Screw Diameter | 1/4 in to 1-1/2 in to ASTM F468; M6 to M36 to ASTM F468M |
| Socket Head Cap Screw Diameter | Size 0 (0.060 in) to 1-1/2 in to ASTM F468 |
| Extended Diameter Range | #00 to 4 in and M1.2 to M48, machined to drawing from certified ASTM B574 material |
| Thread Forms | Metric coarse and fine; UNC and UNF, including the UNR rounded-root form (UNRC and UNRF); 8-thread series (8UN) for 1-1/8 in and larger |
| Thread Production | Rolled or cut |
| Length | Cut and threaded to drawing |
| Custom Dimensions | Machined to drawing in C276 and C22 |
Head style and thread form are selected according to the application drawing and joint design. The available configurations include:
The Hastelloy fastener range includes multiple forms for industrial bolting, joining and assembly applications, including hastelloy screws for machine and equipment assemblies:
Stud bolts for flange connections account for a significant part of the range, while the other forms are supplied according to application and drawing requirements.
Packaging is selected according to fastener size, quantity, supply format and destination. Small lots are packed in sealed poly bags inside labelled cartons, while bulk orders can be placed in wooden cases. Export consignments receive suitable protective and seaworthy packaging.
Each package is identified with the grade, size, heat number and applicable specification. Custom marking can also be provided when specified in the purchase order. As a Hastelloy bolts supplier, Amigo Impex dispatches domestic consignments across pan-India from Mumbai, while export shipments are prepared for the USA, Gulf, European and Asian markets.
Ready-stock requirements can generally be dispatched within 1 to 2 days. Made-to-order fasteners typically require around 30 days, subject to the required grade, size and quantity.
Each Hastelloy fastener lot undergoes the applicable positive material identification, dimensional inspection and thread gauging before packing. Material documentation is checked against the supplied grade and specification, while third-party inspection can be arranged when required by the purchase order.
Each consignment is supplied with the applicable material test certificate. Amigo Impex holds AS 9120B, PED, ISO 9001:2015 and ISO 45001:2018 certifications.
Contact Amigo Impex with the required grade, fastener type, size and quantity for a current quotation.
Request a Quote60–70 tonnes held in Mumbai, with urgent requirements dispatched within one to two days.
AS 9120B, PED, ISO 9001:2015 and ISO 45001:2018, with an MTC on every order.
Cutting, machining, threading, fabrication and testing all handled at our own Mumbai facility.
Original mill certificates plus our own test reports, so every batch can be traced back.
Non-standard sizes and specifications made to order.
Dispatched from Mumbai to every major Indian city, and exported to USA, Gulf, Europe, Asia
Hastelloy fasteners are bolts, nuts, screws, studs and washers machined from nickel alloy bar in grades C276 and C22, for joints exposed to aggressive chemical, chloride and other corrosive environments. In C276, bolts, screws and studs are supplied according to ASTM F468 and nuts according to ASTM F467. C22 is not a listed alloy in either standard, so C22 fasteners are machined from certified ASTM B574 bar to agreed dimensional and property requirements.
Hastelloy C276 is generally selected for reducing acids, mixed corrosive environments, chloride-containing media and sour-service applications. C22 is preferred where stronger oxidising conditions, such as wet chlorine or ferric and cupric chloride exposure, are the primary concern. Final grade selection should be based on the actual process environment and applicable material requirements.
Yes, Hastelloy C276 can be considered for sour-service applications involving H₂S-containing environments where the material meets the applicable requirements of NACE MR0175 / ISO 15156. The specific material condition and service conditions should be confirmed for the application.
Hastelloy fasteners generally cost more because they contain significant amounts of nickel and molybdenum and require specialised machining. Grade, size, thread configuration, quantity and processing requirements also influence the final cost.
Yes, Hastelloy fastener threads can be susceptible to galling during assembly, particularly under high load or without suitable lubrication. An appropriate anti-seize compound and controlled tightening procedure can help reduce the risk. The assembly procedure should follow the requirements of the specific application.
Standard sizes run 1/4" to 1-1/2" and M6 to M36. Smaller and larger diameters, from M1.2 and #00 up to M48 and 4", are machined to customer drawing from certified ASTM B574 material. Metric coarse and fine threads can be supplied, along with UNC and UNF threads, the UNR rounded-root form (UNRC and UNRF) and the 8-thread series for 1-1/8 in and larger, with custom dimensions available to drawing.
Hastelloy fasteners are generally selected for more aggressive chemical and corrosive environments where conventional stainless steel may not provide sufficient resistance. Stainless steel can remain a suitable and more economical choice for less severe service. Material selection should be based on the actual chemical composition, temperature and exposure conditions.
Hastelloy fasteners are used where bolted joints require resistance to aggressive chemicals, chlorides, elevated temperatures or sour-service environments. Major application sectors include:
