Stainless Steel Flanges Supplier to Vietnam

Leading Manufacturer & Exporter of
Stainless Steel Flanges to Vietnam

Werner Flanges stands as Vietnam's trusted partner for premium stainless steel flanges, serving the nation's rapidly expanding oil and gas, petrochemical, and power generation industries. With over two decades of manufacturing excellence and deep expertise in corrosion-resistant piping solutions, we supply ASTM A182 stainless steel flanges that meet the demanding requirements of PetroVietnam projects, offshore gas fields in the Cuu Long Basin, and petrochemical complexes from Dung Quat to Long Son.

Vietnam’s industrial transformation—driven by the Block B-Ô Môn gas development, Nghi Son refinery expansion, and ambitious LNG infrastructure projects—demands piping components that deliver exceptional corrosion resistance, mechanical strength, and longevity. Our stainless steel flanges meet ASME B16.5, DIN, and BS standards while providing the material traceability and quality documentation required by international project specifications.

We manufacture a comprehensive range of stainless steel flanges in grades including ASTM A182 F304/F304L, F316/F316L, and F321, available in pressure classes from 150# to 2500# and sizes from 1/2″ to 60″. Every flange is precision-forged, heat-treated, and thoroughly tested to ensure performance in Vietnam’s challenging industrial environments, from corrosive offshore applications to high-purity pharmaceutical processing.

With strategic shipping partnerships to Hai Phong Port, Cat Lai Port, and Da Nang Port, we deliver stainless steel flanges to project sites across Northern, Central, and Southern Vietnam within 20–25 days via sea freight, with expedited air freight options available for urgent requirements. Our technical team provides comprehensive support for material selection, pressure class determination, and custom manufacturing solutions tailored to Vietnamese industry standards and project specifications.

Vietnam Stainless Steel Flanges | 20–25 Days Sea Freight | Hai Phong, Cat Lai & Da Nang Delivery | Technical & Custom Manufacturing Support

Specifications

Specification	Details
Pressure Rating	Class 150 to Class 2500
Flange Type	Plate Flange
Facing Type	Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ)
Size Range	½” to 24” (DN 15 to DN 600)
Temperature Range	-29°C to +593°C (Depending on Material & Pressure Class)
Applications	Oil & Gas, Petrochemical, Power Generation, Water Treatment, Marine & Industrial Sectors
Manufacturing Process	Forged / Machined
Certification	EN 10204 3.1 / 3.2, IBR, NACE MR0175 / ISO 15156 (as applicable)

Matel and Grade

Type of Materials	Common Specifications / Customization Available on Request
Duplex Steel	ASTM/ASME A182 F51, F60, F61, UNS S31803, UNS S32205
Super Duplex Steel	ASTM/ASME A182 F53, F55, UNS S32750, UNS S32760, F44 (6Mo)
Stainless Steel	ASTM/ASME A182 F304, F304L, F316, F316L, F310, F317L, F321, F347
Carbon Steel	ASTM A105, A350 LF1, LF2, LF3, A266 Class 1/2, A694 F42 to F70, A765 Gr. II
Alloy Steel	ASTM/ASME A182 F1, F5, F9, F11, F12, F22
Non-Ferrous Alloys	Titanium, Brass, Admiralty Brass, Copper Nickel, Nickel Alloys, Hastelloy
Titanium	ASTM/ASME B381 Gr.1, Gr.2, Gr.5, Gr.7, Gr.12, Gr.16
Copper Nickel	ASTM B151 UNS C70600 (Cu-Ni 90/10), C71500 (Cu-Ni 70/30)
Brass, Al-Brass	ASTM B152 UNS C26000, C27200, C28000; ASTM B111 for Al-Brass
Nickel Alloys	ASTM B160, B161, B564 – UNS N02200, N02201, N04400, N08800, N08825, N06600, N06601, N06625, Monel K500
Alloy 20	ASTM B462 UNS N08020
Hastelloy	ASTM B564 UNS N10276 (Hastelloy C276), N06022 (Hastelloy C22)
Cladded Materials	ASTM B898, B265, B424 or custom explosion/clad bonding using dissimilar metals
Cladded Materials	Titanium-Steel, Nickel-Steel, Titanium-Copper, Stainless Steel-Carbon Steel, Bimetallic/Trimetallic Combinations

Types of Flanges

Slip On Flanges	Weld Neck Flanges	Blind Flanges	Socket Weld Flanges	Threaded Flanges
Lap Joint Flanges	Reducing Flanges	Orifice Flanges	Long Weld Neck Flanges	Plate Flanges

Industries and Applications We Supply

Industry	Applications
Oil & Gas Industry	Vietnam’s oil and gas sector, dominated by the state-owned PetroVietnam group, represents the largest consumer of stainless steel flanges in the country. The industry’s expansion into offshore fields, development of marginal reserves, and emphasis on gas monetization creates sustained demand for corrosion-resistant piping components. Offshore Production Platforms: The Nam Con Son Basin, Cuu Long Basin, and Block B-Ô Môn developments feature production platforms where stainless steel flanges provide critical connections in highly corrosive environments. Duplex and super duplex grades (F51, F53) resist chloride stress corrosion cracking from seawater spray while providing the strength required for compact topside piping layouts. Subsea wellhead connections, production manifolds, and riser connections utilize super duplex flanges for their combination of mechanical strength and resistance to sour gas containing H2S and CO2. These flanges must maintain integrity despite continuous exposure to corrosive produced water, thermal cycling from production variations, and dynamic loading from platform motion. Gas Processing Facilities: Vietnam’s transition toward natural gas as primary energy source drives investment in gas processing infrastructure. The Ca Voi Xanh (Blue Whale) gas field development and associated processing facilities require extensive stainless steel piping for amine treating units, dehydration systems, and gas compression. Stainless steel flanges in amine regeneration systems resist the corrosive nature of activated amine solutions, particularly at elevated regeneration temperatures where carbon steel corrosion rates become unacceptable. Grade 316L provides adequate resistance for most amine services, while duplex grades offer enhanced resistance in high-chloride environments. Mercury removal systems, increasingly common as Vietnam exploits offshore gas reserves containing natural mercury, utilize specialized stainless steel materials to resist liquid mercury corrosion that destroys aluminum alloys and carbon steel. Super austenitic or nickel-based alloy flanges provide long-term reliability in these specialized applications. Crude Oil Refineries: The Dung Quat refinery (Quang Ngai Province) and Nghi Son refinery (Thanh Hoa Province) incorporate stainless steel flanges throughout their complex process units. Hydrotreating and hydrocracking units utilize Grade 321 and 347 flanges for their resistance to high-temperature hydrogen attack and sulfidation. Fluid catalytic cracking (FCC) units require stainless steel flanges in regenerator flue gas systems where temperatures exceed 650°C and flue gas contains sulfur compounds that corrode carbon steel. The titanium-stabilized Grade 321 maintains mechanical properties and corrosion resistance under these demanding conditions. Sour water stripper systems, which remove H2S and ammonia from process water, use Grade 316L flanges for their resistance to this corrosive environment. The combination of hydrogen sulfide, ammonia, and water creates conditions that cause rapid corrosion of carbon steel and stress corrosion cracking of some stainless grades. LNG Import Infrastructure: Vietnam’s first LNG import terminal at Thi Vai (Ba Ria-Vung Tau Province) marks the country’s entry into LNG importation to supplement declining domestic gas production. The regasification facility requires extensive use of 316L and 304L stainless steel flanges for cryogenic service (-162°C) where low-temperature toughness is critical. Cryogenic piping systems from LNG storage tanks through vaporizers demand materials that maintain ductility at -162°C without brittle fracture. Austenitic stainless steels retain their face-centered cubic crystal structure at cryogenic temperatures, providing the toughness required for safe LNG service. Charpy impact testing at -196°C verifies adequate toughness. Seawater warming systems that vaporize LNG use titanium or super duplex stainless steel flanges on the seawater side due to the combination of high chloride content, biofouling organisms, and elevated design pressures. Conventional stainless steels experience accelerated corrosion in warm seawater (above 30°C) containing sulfate-reducing bacteria.
Power Generation	Vietnam’s electrical power industry represents the third-largest consumer of stainless steel flanges, with applications spanning thermal, combined-cycle, and renewable energy facilities.Gas-Fired Combined Cycle Plants: PetroVietnam Power operates multiple gas-fired power stations where stainless steel flanges serve in high-temperature steam systems and gas turbine fuel systems. The high-pressure steam superheater and reheater sections require Grade 321 or 347 flanges for creep resistance and oxidation resistance at 540-565°C operating temperatures.Gas turbine exhaust systems transitioning to heat recovery steam generators (HRSG) utilize stainless steel expansion joints and flanges to accommodate thermal expansion while resisting the corrosive products of natural gas combustion. Chromium-nickel stainless alloys resist oxidation and hot corrosion in these applications.Coal-Fired Power Plants: Although Vietnam is transitioning away from coal, existing facilities in Hai Phong and other industrial zones use stainless steel flanges in flue gas desulfurization (FGD) systems and selective catalytic reduction (SCR) systems. The combination of sulfurous acid, chlorides, and elevated temperatures in FGD scrubbers requires duplex or super austenitic stainless steel for adequate corrosion resistance.Boiler feedwater systems utilize Grade 316L flanges in high-purity water service where even trace contamination from carbon steel corrosion causes boiler tube failures. The entire condensate and feedwater train from condenser through deaerator to economizer uses stainless steel to maintain water purity. Biomass and Waste-to-Energy: Vietnam’s growing renewable energy sector includes biomass combustion and municipal waste incineration facilities where stainless steel flanges resist the highly corrosive combustion products. Biomass ash contains alkali metals, chlorides, and sulfur compounds that cause rapid high-temperature corrosion of carbon steel.
Petrochemical Processing	Vietnam’s rapidly expanding petrochemical sector, exemplified by the Long Son Petrochemicals complex in Ba Ria-Vung Tau, creates significant demand for stainless steel flanges resistant to a wide array of chemicals.Olefins Production: The Long Son complex’s steam cracker produces 1,350,000 tons annually of ethylene and propylene feedstocks for downstream plastic production. High-temperature cracking furnaces utilize Grade 321 stainless steel flanges for transfer line connections operating at 800-850°C where thermal cycling and oxidation resistance are critical.Quench water systems that rapidly cool cracked gas require stainless steel flanges resistant to corrosive condensate containing organic acids, hydrogen sulfide, and chlorides. The combination of thermal shock, corrosive environment, and high velocities demands robust materials and design.Compression systems that pressurize cracked gas for downstream processing use Grade 316L flanges for their resistance to condensing organic acids in interstage coolers. The repeated thermal cycling from startup and shutdown operations requires materials that resist thermal fatigue cracking.Polymerization Plants: Polyethylene and polypropylene production facilities utilize stainless steel flanges in catalyst preparation systems, reactor feed systems, and polymer finishing operations. The high-purity requirements of these processes demand stainless steel to prevent contamination from corrosion products that degrade polymer properties. High-pressure polyethylene reactors operating at 1,500-3,000 bar pressure and 150-300°C temperature require Class 1500 or 2500 stainless steel flanges capable of containing these extreme conditions safely. The combination of pressure, temperature, and corrosive monomer requires careful material selection and joint design. Aromatics Production: BTX (benzene, toluene, xylene) extraction and purification facilities use stainless steel flanges in solvent recovery systems where aromatic hydrocarbon compatibility is required. Carbon steel suffers hydrogen attack in these applications, while stainless steel provides long-term reliability. Terephthalic acid production facilities, key to Vietnam’s growing polyester industry, require stainless steel flanges throughout the oxidation, purification, and crystallization sections. The combination of acetic acid solvent, corrosive oxidation byproducts, and elevated temperatures (150-250°C) makes stainless steel the only viable material choice.
Water & Wastewater Treatment	Vietnam’s investment in municipal water infrastructure and industrial wastewater treatment creates steady demand for stainless steel flanges resistant to chlorinated water, ozone, and various treatment chemicals.Desalination Plants: Central Vietnam’s water-scarce provinces are developing desalination capacity using reverse osmosis (RO) and multi-stage flash (MSF) technologies. Seawater intake systems require duplex stainless steel flanges (F51) for resistance to biofouling, pitting corrosion, and stress corrosion cracking in warm seawater.High-pressure RO membrane feed pumps operating at 55-70 bar pressure use Grade 316L flanges for their combination of chloride resistance and mechanical properties. The high-purity permeate water, though corrosivity low, still requires stainless steel to prevent any metallic contamination affecting drinking water quality.Brine discharge systems returning concentrated seawater to the ocean utilize duplex or super duplex flanges depending on brine temperature and concentration. Hot brine (above 60°C) with chloride concentrations exceeding 55,000 ppm (1.6× seawater) can pit conventional austenitic stainless steels, requiring higher-alloy materials.Wastewater Treatment Plants: Municipal wastewater treatment facilities in Hanoi, Ho Chi Minh City, and Da Nang use Grade 316L flanges in chlorination systems, ozone generation equipment, and aeration systems. The combination of chlorine, bacteria-containing water, and ambient temperature creates mildly corrosive conditions where stainless steel provides economical long-term service. Industrial wastewater pretreatment systems, particularly in Vietnam’s textile, food processing, and pharmaceutical sectors, require stainless steel for chemical dosing systems, pH adjustment equipment, and disinfection systems. The variety of chemicals encountered (acids, bases, oxidizers, organic solvents) makes stainless steel the versatile material choice

Frequently Asked Questions (FAQs)

q1: are your stainless steel flanges suitable for vietnam’s coastal marine environments?: yes. we manufacture flanges in grades suitable for marine service including astm a182 f316/f316l with molybdenum for enhanced chloride resistance, and duplex stainless steel grades f51, f53, and f55 providing superior resistance to chloride-induced pitting and stress corrosion cracking. duplex and super duplex grades are recommended for offshore oil and gas platforms, coastal refineries, and desalination plants. material selection guidance is available based on temperature, chloride concentration, and mechanical loading.
q2: what is the typical delivery time for stainless steel flanges to vietnamese project sites?: standard sea freight delivery to major vietnamese ports (hai phong, cat lai, da nang, cai mep-thi vai) requires 20-25 days from order confirmation, including manufacturing, quality testing, packaging, and ocean transit. air freight reduces delivery to 5-7 days for urgent requirements. lead times extend for custom specifications, large quantities, or non-standard materials requiring special procurement. we coordinate with vietnamese logistics partners for customs clearance and inland transportation.
q3: can you provide material certificates complying with vietnamese regulatory requirements?: yes. every shipment includes material test certificates (en 10204 type 3.1 or 3.2) documenting chemical composition, mechanical properties, heat treatment parameters, and test results. additional documentation including dimensional inspection reports, pmi results, ndt reports, and third-party inspection certificates can be provided. certificates are traceable and satisfy petro vietnam specifications and international project standards. documentation is in english, with vietnamese translation available if requested.
q4: do you supply duplex and super duplex stainless steel flanges for offshore applications?: yes. we manufacture duplex (f51, f52, f60) and super duplex (f53, f55) stainless steel flanges for vietnam’s offshore oil and gas sector. these grades offer higher strength-to-weight ratios than austenitic 316l, resist chloride stress corrosion cracking, pitting, and sour gas (h2s/co2), and are ideal for subsea pipelines, production manifolds, and topside processing equipment. nance mr0175/iso 15156 compliance documentation is provided.
q5: can flanges be manufactured to custom specifications for special vietnamese project requirements?: yes. custom manufacturing includes non-standard dimensions, special materials, unique facing configurations, enhanced testing and documentation, and project-specific requirements. our engineering team collaborates with vietnamese project engineers to meet technical requirements. lead time depends on complexity, typically 4-6 weeks beyond standard delivery times.
q6: what quality inspections and testing do you perform before shipment to vietnam?: all flanges undergo dimensional verification per asme b16.5, positive material identification (pmi) using xrf, visual inspection, verification of markings and documentation, and mechanical testing (tensile, impact, hardness). optional ndt includes liquid penetrant, magnetic particle, ultrasonic, or radiographic testing. third-party inspection by tuv, dnv, lloyd’s, bv, sgs can be arranged. complete documentation accompanies every shipment for customs clearance and project verification.
q7: are your stainless steel flanges suitable for pharmaceutical and food industry applications in vietnam?: yes. we manufacture sanitary-grade stainless steel flanges meeting food contact and pharmaceutical standards. grades f304l and f316l are fda-compliant. surface finishes range from standard machined (125-250 μm ra) to electropolished ≤0.8 μm ra. materials provide full traceability and resist bacterial growth, cip/sip cycles, and are used in vietnamese pharmaceutical and food production facilities. certificates of compliance with food contact regulations and gmp requirements are provided.