LEADING METAL GASKETS MANUFACTURER, EXPORTER & SUPPLIER
Manufacturer, Exporter & Supplier of Premium Industrial Gaskets
Sunflex Metalloy is a precision manufacturer of Stainless Steel industrial gaskets — supplying the complete range of SS gasket types across all major stainless steel grades to the petrochemical, oil and gas, pharmaceutical, power generation, chemical processing, and food and beverage industries worldwide. From standard flat ring gaskets to precision-engineered Spiral Wound, Ring Type Joint (RTJ), Kammprofile, Corrugated, Metal Jacketed, Lens Ring, and Solid Metal designs, we manufacture every form of stainless steel gasket to ANSI, ASME, DIN, BS, JIS, and API standards — in both standard and fully custom dimensions.
Our stainless steel gaskets are manufactured from certified raw material across the widest range of SS grades — including SS 304, SS 304L, SS 316, SS 316L, SS 321, SS 347, SS 310, SS 310S, Duplex 2205, and Super Duplex 2507 — giving engineers and procurement teams the material flexibility to match the exact corrosion resistance, temperature, and mechanical strength requirements of their application. Every Sunflex Metalloy SS gasket is dimensionally inspected and supplied with full material test certificates (MTC) as per EN 10204 3.1 or 3.2.
Grades Available: SS 304 · SS 304L · SS 316 · SS 316L · SS 321 · SS 347 · SS 310 · SS 310S · Duplex 2205 · Super Duplex 2507
Stainless Steel is the most widely specified metallic gasket material in the process industry — and for good reason. Its combination of mechanical strength, corrosion resistance, temperature performance, and availability across a broad range of alloy compositions makes it the versatile, reliable choice for the majority of industrial flanged joint applications. Whether the service environment involves high-temperature steam, corrosive process chemicals, cryogenic media, or hygienic process fluids, there is a stainless steel grade engineered to handle it.
The corrosion resistance of stainless steel derives from its chromium content — a minimum of 10.5% chromium by composition — which forms a passive, self-repairing oxide layer on the metal surface that protects against oxidation and chemical attack. By varying the alloying elements, metallurgists have developed a family of stainless steel grades covering applications from mild atmospheric service through to the most aggressive acid, chloride, and high-temperature environments.
At Sunflex Metalloy, we manufacture stainless steel gaskets across the austenitic, ferritic, and duplex families — giving our customers access to the full spectrum of SS performance from the economical SS 304 standard grade through to the advanced Super Duplex 2507 for the most demanding offshore and chemical service environments.
| Grade | UNS | Key Properties | Typical Application |
|---|---|---|---|
| SS 304 | S30400 | General corrosion resistance, most widely used | General process piping, food industry, water systems |
| SS 304L | S30403 | Low carbon, improved weld corrosion resistance | Welded assemblies, sensitization-prone applications |
| SS 316 | S31600 | Enhanced chloride & acid resistance (Mo) | Chemical processing, marine-adjacent, pharmaceuticals |
| SS 316L | S31603 | Low carbon SS 316 for welded service | Process plant welded piping, pharmaceutical equipment |
| SS 321 | S32100 | Titanium-stabilized, high temperature resistance | High-temperature process piping, exhaust systems |
| SS 347 | S34700 | Niobium-stabilized, superior weld stability | Petrochemical high-temp service, power generation |
| SS 310 / 310S | S31000 | Maximum oxidation resistance to 1100°C | Furnaces, kilns, high-temperature heat treatment |
| Duplex 2205 | S32205 | High strength + pitting/SCC resistance | Offshore, chemical plant, desalination |
| Super Duplex 2507 | S32750 | Superior chloride & acid resistance, very high strength | Offshore subsea, aggressive chemical service |
Sunflex Metalloy manufactures all eight major Stainless Steel gasket types — each engineered for specific flange configurations, pressure classes, temperature ranges, and process media.
Stainless Steel Ring Type Joint (RTJ) gaskets are solid metallic sealing rings machined to precision tolerances for use with RTJ flange faces — the standard high-pressure flange type in oil and gas, petrochemical, and offshore process applications. When installed and torqued to specification, the SS ring seats into the precision-machined trapezoidal groove of the RTJ flange, deforming plastically to create a high-integrity metal-to-metal seal capable of withstanding extreme operating pressures, elevated temperatures, and aggressive process fluids.
Sunflex Metalloy manufactures SS RTJ gaskets in R-type oval and octagonal profiles, as well as RX and BX pressure-energized types for subsea and wellhead applications. Available in SS 304, SS 316, SS 316L, SS 321, and duplex grades — with grade selection guided by the corrosivity of the process fluid, the operating temperature, and the applicable project specification or NACE requirement.
Stainless Steel Spiral Wound gaskets are the most widely used semi-metallic gasket type in the process industry — the default sealing solution for the vast majority of raised face flanged joints in refineries, chemical plants, power stations, and general process piping worldwide. Constructed by spirally winding a thin SS metallic strip alternately with a soft filler material — typically flexible graphite or PTFE — the spiral wound gasket creates a series of alternating hard and soft layers that compress under bolt load to produce a resilient, self-energizing seal.
Sunflex Metalloy manufactures SS spiral wound gaskets in all standard configurations — plain wound, with inner ring, with outer ring, and with both inner and outer rings — in compliance with ASME B16.20.
Stainless Steel Corrugated Metal gaskets are manufactured by forming a precision SS sheet into a series of concentric corrugations across the gasket face. The raised corrugation ridges concentrate the bolt load onto narrow contact lines — effectively multiplying the sealing contact stress across multiple independent sealing lines while significantly reducing the total bolt load required to achieve sealing compared to a flat solid gasket.
Corrugated SS gaskets can be supplied in plain form or with a soft overlay layer — typically flexible graphite or PTFE. Sunflex Metalloy manufactures SS corrugated gaskets in SS 304, SS 316, SS 316L, and SS 321 grades, in standard and custom dimensions.
Stainless Steel Metal Jacketed gaskets consist of a compressible soft filler core — typically flexible graphite, ceramic fibre, compressed non-asbestos fibre (CNAF), or PTFE — enclosed within a formed Stainless Steel outer jacket. The SS jacket provides mechanical protection, chemical resistance, and structural rigidity to the gasket assembly, while the soft inner filler provides the compressibility and conformability required to seal against flange surface imperfections at moderate bolt loads.
Sunflex Metalloy manufactures SS Metal Jacketed gaskets in single-jacketed and double-jacketed configurations, in SS 304, SS 316, SS 316L, and SS 321 jacket grades.
Stainless Steel Solid Metal gaskets are manufactured entirely from solid SS bar or sheet stock — no composite layers, no filler material, no bonded components. This all-metal, single-material construction delivers the highest mechanical strength and the broadest temperature range of any gasket form in the stainless steel range.
Sunflex Metalloy manufactures solid SS gaskets in flat ring, lens ring, oval ring, octagonal ring, and fully custom machined profiles. High-temperature grades — SS 321, SS 347, SS 310, and SS 310S — are particularly specified for furnace, kiln, and high-temperature process applications. Duplex and Super Duplex grades are available for aggressive offshore and chemical service environments.
Stainless Steel Lens Ring gaskets are precision CNC-machined solid metal sealing rings with a distinctive convex spherical cross-section profile. The SS lens ring gasket seals through line contact — the convex spherical outer surface contacts the matching concave conical seat machined into the flange face at a single circular line, concentrating the entire bolt load onto a very narrow contact area to generate extremely high sealing stress even at relatively modest bolt loads.
This concentrated line-contact sealing mechanism makes SS Lens Ring gaskets exceptionally capable at very high operating pressures — often specified in high-pressure gas pipeline systems, compressor station flanges, and high-pressure instrumentation connections where pressures may reach several hundred bar.
Stainless Steel Octagonal and Oval Ring gaskets are solid metallic sealing rings designed for use with Ring Type Joint (RTJ) flanges in high-pressure oil and gas, petrochemical, and offshore process applications. Both profiles seat into the precision-machined trapezoidal groove of an RTJ flange and create a metal-to-metal seal through the controlled plastic deformation of the SS ring under bolt loading.
Sunflex Metalloy manufactures both profiles in SS 304, SS 316, SS 316L, SS 321, Duplex 2205, and Super Duplex 2507 across all API standard ring numbers and custom dimensions.
Stainless Steel Kammprofile gaskets are the premium engineered sealing solution for critical flanged joints in process industry heat exchangers, pressure vessel nozzles, and column flanges. The Kammprofile design features a solid SS metal core with precision-machined concentric serrated grooves on both faces, typically covered with a bonded soft overlay of flexible graphite or PTFE. Under bolt compression, the sharp SS serration ridges cut through the soft overlay, creating multiple high-stress sealing lines across the gasket face.
The solid SS core gives Kammprofile gaskets outstanding blowout resistance, dimensional stability under thermal cycling, and resistance to gasket relaxation. The practical advantage is reusability — the solid machined SS core can be re-overlaid with fresh graphite or PTFE at maintenance, significantly reducing long-term sealing cost per joint.
Match your operating conditions, flange type, and pressure class to the right SS gasket form:
| Gasket Type | Pressure Class | Temp Range | Flange Face Type | Reusable | Best Application |
|---|---|---|---|---|---|
| Ring Type Joint (RTJ) | Class 600–2500 | Cryogenic to 600°C | RTJ Groove | No | Petrochemical, offshore, wellhead |
| Spiral Wound | Class 150–2500 | Cryogenic to 600°C | RF, FF, T&G | No | Process piping, refineries, power plants |
| Corrugated Metal | Class 150–900 | Up to 350°C | RF, FF | No | Process vessels, low bolt load flanges |
| Metal Jacketed | Class 150–900 | Up to 400°C | FF, RF, MF, T&G | No | Heat exchanger covers, large flanges |
| Solid Metal | Class 150–2500 | Cryogenic to 600°C | All types | No | Extreme service, high-temp furnace flanges |
| Lens Ring | Ultra-high pressure | Up to 400°C | Concave conical seat | No | High-pressure pipelines, compressors |
| Octagonal / Oval Ring | Class 600–2500 | Up to 400°C | RTJ Groove | No | Oilfield, offshore, sour service |
| Kammprofile | Class 150–2500 | Cryogenic to 600°C | RF, FF, MF, T&G | Yes (core) | Heat exchangers, process vessels |
Selecting the correct stainless steel grade for your gasket is just as important as selecting the correct gasket type. The wrong grade can result in premature corrosion, stress corrosion cracking, or mechanical failure. The following guidance covers the most common application scenarios:
Use SS 304 / SS 304L when: Operating in non-chloride environments with mild process fluids, water, or atmospheric conditions. SS 304L is preferred when the gasket will be used in or near welded assemblies where sensitization resistance is important.
Use SS 316 / SS 316L when: Operating in chloride-containing environments, marine-adjacent conditions, or acidic process media where the additional molybdenum content of SS 316 is required for pitting and crevice corrosion resistance. SS 316L is specified for welded service.
Use SS 321 when: Operating at elevated temperatures between 425°C and 900°C where standard SS 304 or SS 316 would be susceptible to sensitization. The titanium stabilization of SS 321 prevents carbide precipitation and intergranular corrosion at high temperatures.
Use SS 347 when: Operating at high temperatures in aggressive petrochemical or power generation service where the niobium stabilization of SS 347 provides superior weld stability and creep resistance compared to SS 321.
Use SS 310 / SS 310S when: Operating at extreme temperatures above 900°C — furnace components, kiln flanges, high-temperature heat treatment equipment — where maximum oxidation resistance is the primary requirement.
Use Duplex 2205 when: Operating in chloride-containing process environments, offshore or coastal locations, or chemical processing where higher mechanical strength and superior resistance to stress corrosion cracking and pitting are required compared to standard austenitic grades.
Use Super Duplex 2507 when: Operating in the most demanding offshore, subsea, or chemical environments — highly concentrated chloride media, high-pressure aggressive process streams, or where the highest available combination of strength and corrosion resistance in the duplex family is needed.
Every SS gasket manufactured and certified to international standards.
