LEADING METAL GASKETS MANUFACTURER, EXPORTER & SUPPLIER
Manufacturer, Exporter & Supplier of Premium Industrial Gaskets
All Types of Hastelloy Industrial Gaskets in C-276, C-22, C-2000, B-3, G-30 & X — Precision Manufactured for the Most Aggressive Chemical, Wet Process & Corrosive Industrial Environments
Sunflex Metalloy is a specialist manufacturer of Hastelloy industrial gaskets — supplying the complete range of gasket types across all major Hastelloy nickel-molybdenum and nickel-molybdenum-chromium superalloy grades to the chemical and specialty chemical processing, chlor-alkali manufacturing, flue gas desulfurization (FGD), pharmaceutical and fine chemical, fertilizer and phosphate processing, pulp and paper, offshore oil and gas sour service, and nuclear waste processing industries. From precision Ring Type Joint (RTJ) and Spiral Wound gaskets for high-pressure corrosive process service, to Kammprofile, Corrugated, Metal Jacketed, Lens Ring, and Solid Metal designs for the most aggressively corrosive wet process environments, we manufacture every form of Hastelloy sealing solution to ANSI, ASME, DIN, BS, JIS, API, and NACE standards.
Hastelloy alloys represent the absolute pinnacle of industrial corrosion resistance — developed specifically for process environments so chemically aggressive that virtually no other engineering material can provide acceptable service life. Where stainless steel, Monel, and even Inconel are chemically attacked and fail, Hastelloy endures. The defining capability of Hastelloy C-family alloys is their simultaneous resistance to both strongly oxidizing and strongly reducing corrosion conditions. Every Sunflex Metalloy Hastelloy gasket is manufactured from certified raw material with full chemical and mechanical traceability, dimensionally inspected, and supplied with MTC as per EN 10204 3.1 or 3.2.
Grades Available: Hastelloy C-276 · Hastelloy C-22 · Hastelloy C-2000 · Hastelloy B-3 · Hastelloy G-30 · Hastelloy X · UNS N10276 · UNS N06022 · UNS N10675 · UNS N06030 · UNS N06002
Hastelloy is the collective trade name for a family of high-performance nickel alloys — predominantly nickel-molybdenum and nickel-molybdenum-chromium compositions — developed specifically for process environments where corrosion resistance requirements exceed the capabilities of every other class of engineering material. The Hastelloy alloy family has been the material of last resort — and often the only technically viable material — in chemical process engineering for over eighty years.
The defining characteristic that separates Hastelloy C-family alloys from all other corrosion-resistant materials — including austenitic stainless steel, duplex stainless steel, Monel, and even Inconel — is their ability to resist both strongly oxidizing and strongly reducing corrosion conditions simultaneously. Hastelloy C-276 and C-22, through their carefully balanced nickel-chromium-molybdenum compositions, resist both attack modes — making them uniquely versatile in process environments with mixed or variable chemistry.
Beyond their broad acid resistance, Hastelloy alloys offer exceptional resistance to chloride-induced pitting and crevice corrosion, wet chlorine gas and hypochlorite solutions, and stress corrosion cracking in chloride environments — all failure modes that represent serious limitations for stainless steel in chemical process service.
| Grade | UNS | Key Composition | Defining Corrosion Resistance | Primary Application |
|---|---|---|---|---|
| Hastelloy C-276 | N10276 | Ni-Mo-Cr-W | Outstanding resistance to oxidizing & reducing acids, wet chlorine, hypochlorite, mixed acids | Chemical processing, FGD, chlor-alkali, waste treatment |
| Hastelloy C-22 | N06022 | Ni-Cr-Mo-W | Enhanced oxidizing media resistance vs C-276, superior mixed acid performance | Pharmaceutical, fine chemical, mixed acid streams |
| Hastelloy C-2000 | N06200 | Ni-Cr-Mo-Cu | Broadest corrosion resistance of all C-family — both oxidizing and reducing | Variable chemistry processes, universal corrosion resistance |
| Hastelloy B-3 | N10675 | Ni-Mo | Exceptional HCl resistance at all concentrations and temperatures | HCl absorption, handling, and processing systems |
| Hastelloy G-30 | N06030 | Ni-Cr-Mo-Fe | Unmatched phosphoric and sulfuric acid resistance | Fertilizer, phosphate processing, WPA service |
| Hastelloy X | N06002 | Ni-Cr-Mo-Fe | High-temperature oxidation resistance combined with moderate corrosion resistance | Gas turbines, industrial furnaces, high-temp process |
Sunflex Metalloy manufactures all eight major Hastelloy gasket types — each engineered for the specific pressure classes, temperature ranges, flange configurations, and the uniquely aggressive chemical environments where Hastelloy is the required or mandated gasket material.
Hastelloy Ring Type Joint (RTJ) gaskets are precision-machined solid Hastelloy sealing rings designed for use with RTJ flange faces — delivering the highest tier of metal-to-metal sealing integrity in the most severely corrosive chemical process, chlor-alkali, FGD, and offshore sour service applications. When torqued to specification, the Hastelloy ring seats into the precision-machined trapezoidal groove of the RTJ flange, deforming plastically under bolt load to create a high-integrity metal-to-metal seal.
Hastelloy C-276 is the most widely specified grade for RTJ gaskets in chemical process and FGD service. Hastelloy C-22 is preferred where the process chemistry is predominantly oxidizing. Hastelloy B-3 is the mandatory specification for RTJ connections in hydrochloric acid absorption and handling systems. Sunflex Metalloy manufactures Hastelloy RTJ gaskets in oval and octagonal profiles and RX/BX pressure-energized types to ASME B16.20 and API 6A, across all standard ring numbers and custom dimensions.
Hastelloy Spiral Wound gaskets are semi-metallic sealing elements constructed by spirally winding a thin Hastelloy metallic strip alternately with a soft filler material — typically PTFE for the broadest chemical compatibility in aggressive acid and chloride service, or flexible graphite for moderate-temperature chemical service. The Hastelloy winding strip provides the extraordinary corrosion resistance of the superalloy in a spiral wound gasket format — delivering reliable, long-service sealing in process environments where stainless steel, Monel, and even Inconel winding strips would be chemically attacked.
Hastelloy C-276 spiral wound gaskets are the standard specification for the most demanding chemical process flanged piping. PTFE filler is the universal standard for Hastelloy winding gaskets — providing complete chemical resistance to virtually all acids, chlorides, and oxidizing agents encountered in Hastelloy-specified process environments. Sunflex Metalloy manufactures Hastelloy spiral wound gaskets to ASME B16.20 in all standard sizes and custom dimensions.
Hastelloy Corrugated Metal gaskets are manufactured by precision-forming a Hastelloy alloy sheet into a series of concentric corrugations across the gasket face — creating multiple raised contact ridges that concentrate the available bolt load onto narrow sealing lines and establish multiple simultaneous independent sealing paths. The all-Hastelloy corrugated construction ensures complete corrosion resistance across the entire gasket face — critical in applications such as FGD absorber vessel connections, chlor-alkali column flanges, and acid scrubber equipment flanges where any localized corrosion could compromise sealing integrity.
Available plain (bare Hastelloy) for service in the most aggressive media where overlay materials would be chemically attacked, or with a PTFE overlay for additional conformability and chemical barrier performance in moderate-temperature acid service. Sunflex Metalloy manufactures Hastelloy corrugated gaskets in C-276, C-22, and B-3 grades in standard and custom dimensions.
Hastelloy Metal Jacketed gaskets consist of a compressible soft filler core — typically PTFE for aggressive acid and chloride service, or flexible graphite for moderate-temperature chemical environments — enclosed within a formed Hastelloy metal outer jacket. The Hastelloy jacket provides the outer sealing surface and complete chemical protection for the soft inner filler against the most aggressive process media — wet chlorine, mixed acids, concentrated mineral acids, hypochlorite, and highly oxidizing chemical streams.
Hastelloy Metal Jacketed gaskets are particularly critical in large-diameter chemical process flanges and reactor closure applications where the gasket must simultaneously provide corrosion resistance in the most aggressive chemical service environments and seal effectively at moderate bolt loads. PTFE inner filler — selected for its complete chemical inertness — provides the conformability needed on large-diameter flanges. Sunflex Metalloy manufactures Hastelloy jacketed gaskets in C-276, C-22, and B-3 grades in single and double-jacketed configurations.
Hastelloy Solid Metal gaskets represent the absolute highest tier of corrosion-resistant industrial sealing — manufactured entirely from solid Hastelloy bar, plate, or sheet stock with no composite layers, no filler materials, and no bonded components of any kind. The all-Hastelloy single-material construction delivers the complete, undiluted chemical resistance and mechanical performance of the Hastelloy superalloy at every point across the gasket sealing face.
Hastelloy C-276 is the standard grade for solid metal gaskets in the most aggressive general chemical service. Hastelloy C-22 is preferred for predominantly oxidizing acid environments and pharmaceutical process equipment. Hastelloy B-3 is the definitive grade for solid metal gaskets in pure hydrochloric acid service at all concentrations and temperatures. Hastelloy G-30 is the specification for solid gaskets in phosphoric acid and WPA process environments.
Hastelloy Lens Ring gaskets are precision CNC-machined solid Hastelloy sealing rings with a convex spherical cross-section profile — engineered for ultra-high-pressure sealing in the most aggressively corrosive chemical process environments where standard metallic lens ring materials would be chemically attacked and fail within the design service life. The convex spherical profile contacts the matching concave conical seat of the mating flange at a single circular line — concentrating the assembly load onto a very narrow contact area to generate extremely high sealing stress.
Hastelloy C-276 lens ring gaskets are specified in ultra-high-pressure instrumentation connections, chemical injection points, and high-pressure process pipeline connections in chemical plants where the process media mandates Hastelloy material throughout the system. Sunflex Metalloy manufactures Hastelloy lens ring gaskets to DIN 2696 and custom specifications, precision CNC-machined from certified Hastelloy bar.
Hastelloy Octagonal and Oval Ring gaskets are precision-machined solid Hastelloy sealing rings for use with Ring Type Joint (RTJ) flanges in high-pressure aggressive chemical process, FGD, chlor-alkali, and offshore sour service applications. Both profiles seat into the trapezoidal groove of the RTJ flange and create a metal-to-metal seal through controlled plastic deformation of the Hastelloy ring under bolt loading — with the all-Hastelloy construction providing complete corrosion resistance at the sealing interface.
Hastelloy C-276 is the standard and most widely specified grade for oval and octagonal ring gaskets across the broadest range of aggressive chemical process and FGD applications. Hastelloy B-3 is the mandatory specification for RTJ ring gaskets in pure HCl service. Hastelloy G-30 rings are the standard for phosphoric acid and wet process acid RTJ connections. Sunflex Metalloy manufactures both oval and octagonal profiles across all API standard ring numbers and custom dimensions.
Hastelloy Kammprofile gaskets combine the extraordinary corrosion resistance of Hastelloy superalloy with the precision multi-line sealing geometry and practical reusability of the Kammprofile design. The gasket features a solid Hastelloy metal core with precision CNC-machined concentric serrated grooves on both faces, covered with a bonded soft overlay of PTFE — selected as the standard overlay for Hastelloy Kammprofile gaskets for its complete chemical inertness across the entire range of aggressive acid, chloride, and oxidizing media encountered in Hastelloy-specified process applications.
The engineering case for Hastelloy Kammprofile gaskets is particularly compelling in the chemical process industry — where the capital cost of Hastelloy process equipment is very high, plant availability is a critical commercial priority, and aggressive process chemistry makes gasket replacement technically demanding and operationally disruptive. The reusability of the solid Hastelloy Kammprofile core — inspected, re-overlaid with fresh PTFE, and reinstalled at each plant turnaround — delivers significant long-term maintenance cost advantage.
Match your process media, pressure class, flange configuration, and operating temperature to the right Hastelloy gasket form:
| Gasket Type | Pressure Class | Temp Range | Flange Face Type | Reusable | Best Application |
|---|---|---|---|---|---|
| Ring Type Joint (RTJ) | Class 150–2500 | Up to 650°C | RTJ Groove | No | Chemical process, FGD, HCl service, offshore |
| Spiral Wound | Class 150–2500 | Up to 650°C | RF, FF, T&G | No | Aggressive acid piping, FGD, chlor-alkali |
| Corrugated Metal | Class 150–900 | Up to 600°C | RF, FF | No | Chemical vessels, scrubbers, limited bolt load |
| Metal Jacketed | Class 150–900 | Up to 650°C | FF, RF, MF, T&G | No | Reactor closures, FGD vessels, large flanges |
| Solid Metal | Class 150–2500 | Up to 1000°C+ | All types | No | Maximum corrosion integrity, all acid service |
| Lens Ring | High pressure | Up to 650°C | Conical seat | No | Chemical instrument connections, HCl fittings |
| Octagonal / Oval Ring | Class 150–2500 | Up to 650°C | RTJ Groove | No | Chemical RTJ, FGD, HCl, phosphoric acid |
| Kammprofile | Class 150–2500 | Up to 650°C | RF, FF, MF, T&G | Yes (core) | Chemical heat exchangers, reusable acid sealing |
Hastelloy grade selection is the most critical engineering decision in specifying a Hastelloy gasket — each grade has been specifically formulated for a defined range of corrosive conditions, and selecting the correct grade ensures maximum service life, reliability, and value.
Hastelloy C-276 (UNS N10276) — Your process involves a combination or mixture of oxidizing and reducing corrosive conditions — mixed acid streams, alternating acid chemistries, wet chlorine gas, sodium hypochlorite, sulfuric acid, hydrochloric acid, or any process where the corrosive conditions are variable, complex, or not precisely defined. C-276 is the most broadly corrosion-resistant single-grade specification across the widest range of aggressive chemical environments — the default Hastelloy specification globally.
Hastelloy C-22 (UNS N06022) — Your process is predominantly oxidizing — involving nitric acid, mixed nitric/hydrofluoric acid, highly oxidizing hypochlorite solutions, or strongly oxidizing mixed acid streams. Also the preferred grade for pharmaceutical and fine chemical manufacturing where its very low carbon content provides maximum resistance to sensitization and intergranular corrosion near welded connections.
Hastelloy C-2000 (UNS N06200) — Your process chemistry is variable, undefined, or subject to change — and you need the single Hastelloy grade with the broadest corrosion resistance envelope covering both reducing and oxidizing conditions across the widest range of acid concentrations and temperatures. Specify C-2000 where process chemistry is complex, variable, or uncertain.
Hastelloy B-3 (UNS N10675) — Pure hydrochloric acid (HCl) resistance at all concentrations and temperatures is the primary requirement. Hastelloy B-3 is the only commonly available engineering alloy that provides reliable, long-term resistance to HCl across all acid concentrations — from dilute solutions through to concentrated HCl — and at elevated temperatures. Important caveat — B-3 must not be used where the process stream contains oxidizing agents (dissolved oxygen, ferric ions, nitric acid).
Hastelloy G-30 (UNS N06030) — Phosphoric acid — particularly wet process phosphoric acid (WPA) — is the primary process medium. G-30 was specifically engineered for phosphoric acid service and delivers superior performance in WPA environments compared to C-276, C-22, or any other Hastelloy grade.
Hastelloy X (UNS N06002) — High-temperature oxidation resistance is required alongside moderate corrosion resistance — typically in gas turbine hot section components, industrial furnace connections, and high-temperature process equipment operating at temperatures above the reliable service range of C-276 and other C-family grades.
