Weld Neck Flanges Supplier to Thailand

LEADING MANUFACTURER & EXPORTER OF
WELD NECK FLANGES TO THAILAND

With over 20 years of specialized experience in precision flange manufacturing, Werner Flanges has established itself as a trusted supplier of weld neck flanges to Thailand's dynamic oil & gas, petrochemical, and power generation sectors. Our manufacturing facility combines advanced CNC machining technology with rigorous quality control processes, enabling us to deliver flanges that exceed the demanding standards of Thailand's major industrial operators including PTT, Thai Oil (TOP), PTTGC, and IRPC.

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Thailand’s thriving industrial base—particularly in the Map Ta Phut petrochemical complex in Rayong province and the Bangkok metropolitan region—requires reliable piping solutions for complex fluid handling systems. Weld neck flanges are critical components in these applications, engineered for the extreme pressures and temperatures encountered in oil refining, gas processing, and power generation industries. Our comprehensive product range covers all ASME B16.5 pressure classes (150#, 300#, 600#, 900#, 1500#, 2500#) in sizes from 1/2″ to 60″, manufactured in carbon steel, stainless steel, alloy steel, and duplex materials.

Our Thailand-focused logistics network ensures delivery to major industrial hubs within 18-22 days via sea freight to Laem Chabang Port (Thailand’s primary deep-sea gateway) or Bangkok Port, with expedited 5-7 day air freight options for critical shipments. Every flange exported includes comprehensive documentation: Material Test Certificates (MTC), PMI reports, dimensional inspection data, and heat treatment charts—ensuring full compliance with Thai industrial standards and international regulations.

Weld neck flanges feature a tapered hub transitioning into a cylindrical neck, which is welded directly into the pipe. This design creates an exceptionally strong connection distributing stress evenly across the flange diameter, making them the preferred choice for high-pressure, high-temperature, and critical applications.

Weld Neck Flanges | Tapered Hub Design | High-Pressure & High-Temperature Applications | Superior Stress Distribution

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

Weld Neck Flanges	Raised Face Weld Neck Flanges	Flat Face Weld Neck Flanges	RTJ Weld Neck Flanges	Long Weld Neck Flanges
High Pressure Weld Neck Flanges	Forged Weld Neck Flanges	Reducing Weld Neck Flanges	Industrial Weld Neck Flanges	Custom Weld Neck Flanges

Industries and Applications We Supply

Industry	Applications
Oil & Gas Industry	Thailand’s offshore platforms in the Gulf of Thailand, integrated refineries (Thai Oil, PTTGC, IRPC), and midstream pipeline operations depend on ASME B16.5 weld neck flanges: Upstream Production: Wellhead connections at 500-3,000 PSI require 600#-1500# flanges in A105 (general crude) or F11 (hydrogen service >500 PSI H₂). Subsea pipeline terminations use 300#-600# A105 flanges, with F51 duplex specified for subsea corrosion exposure. Refining Operations: Crude distillation units operate at 600-900°F and 50-200 PSI using 300# A105 inlet/outlet flanges. Hydrotreating units (500-3,000 PSI with >500 PSI H₂) exclusively specify ASME B16.5 weld neck flanges in ASTM A350 LF2 or A182 F11 with full NACE MR0175 certification. Hydrogen generation via steam methane reforming (1,500-1,800°F, 300-400 PSI) uses 900#-1500# A182 F91 flanges with specialized thermal protection. Midstream & Distribution: Product pipelines to Laem Chabang and Bangkok Ports use 150#-300# A105 flanges, 4″-36″ diameters. Marine terminals feature 150#-300# flanges for tank nozzles and 600# for bottom-loading pressure control systems. Petrochemical Industry Map Ta Phut Petrochemical Complex (one of Asia’s largest) utilizes weld neck flanges throughout operations: Cracking Furnaces: Ethane/naphtha cracking at 1,500°F+ uses 900# ASME B16.5 weld neck flanges in A182 F91 with thermal protection systems. Polymerization Reactors: 250-500°F, 500-3,000 PSI operation uses 600#-1500# flanges in A105 (general service) or F11 (hydrogen-containing processes). Specialty Chemical Synthesis: MMA, PO, and acrylonitrile production in 2,000-3,000 PSI autoclaves requires 2500# small-diameter (1″-4″) flanges with full ASME B31.3 and Section VIII certification.
Power Generation	Thailand’s electricity infrastructure transition includes natural gas CCGT plants, coal-fired facilities, and renewable energy:CCGT Plants (Songkhla, Rayong, Bangkok metro): Gas turbine outlets at 1,100-1,300°F connect via 900# A182 F91 flanges, 6″-12″ diameter. HRSG high-pressure superheaters at 1,000-1,050°F and 1,200-1,800 PSI use 1500#-2500# A182 F91 small-diameter flanges.Coal-Fired Plants: Boiler outlets at 2,500+ PSI and 1,050°F+ require 1500#-2500# A182 F91 flanges with complete ASME Section I certification.
Petrochemical Processing	Map Ta Phut Petrochemical Complex (one of Asia’s largest) utilizes weld neck flanges throughout operations:Cracking Furnaces: Ethane/naphtha cracking at 1,500°F+ uses 900# ASME B16.5 weld neck flanges in A182 F91 with thermal protection systems.Polymerization Reactors: 250-500°F, 500-3,000 PSI operation uses 600#-1500# flanges in A105 (general service) or F11 (hydrogen-containing processes).Specialty Chemical Synthesis: MMA, PO, and acrylonitrile production in 2,000-3,000 PSI autoclaves requires 2500# small-diameter (1″-4″) flanges with full ASME B31.3 and Section VIII certification.
Water & Wastewater Treatment	RO Desalination: 800-1,000 PSI membrane vessels use 600#-900# A182 F316L flanges, 1″-3″ diameters. Product water delivery at atmospheric pressure uses 150#-300# A105 flanges.Wastewater Treatment: Chemical feed systems for chlorine/ozone at up to 300 PSI use 300# stainless steel flanges.

Frequently Asked Questions (FAQs)

Q: weld neck vs. slip-on flange differences?: weld neck flanges feature a cylindrical neck welded directly into the pipe—tapered hub provides superior stress distribution and strength, ideal for high-pressure/high-temperature critical applications. slip-on flanges slide over the pipe with dual-side fillet welds—less robust, suitable only for non-critical systems. thai petrochemical and refinery applications standardize weld neck for critical piping.
Q: what pressure class should i specify?: selection depends on maximum system pressure. common classes: 150# (285 psi), 300# (740 psi), 600# (1480 psi), 900# (2220 psi). apply a 1.5× safety factor. for example, a 500 psi system would typically use 300# flanges.
Q: what material for corrosive service?: carbon steel a105 for non-corrosive service, type 304l for mild corrosion or seawater, type 316l for enhanced chloride resistance, duplex f51/f53 for extreme environments. thailand’s coastal petrochemical facilities typically specify 316l or duplex due to chloride and humidity corrosion risk.
Q: delivery time to thailand?: standard sea freight: 18-22 days to laem chabang plus 1-3 days local delivery. expedited air freight: 5-7 days total.
Q: custom sizes/specifications available?: yes. we can manufacture non-standard sizes, specialty materials (hastelloy, monel, inconel), custom coatings, and integrated instrumentation. custom projects typically require 6-8 weeks.
Q: suitable for hydrogen processing?: yes. asme b16.5 weld neck flanges in astm a350 lf2 or a182 f11, nace mr0175 verified, are standard for hydrogen processing plants in thailand, including pttgc and irpc facilities.