Phanuphong Steel and Plates stands out as a top-notch manufacturer and supplier of Carbon Steel Weld Neck Flanges, proudly based in Bangkok, Thailand. With a strong focus on quality and engineering excellence, the company provides flanges that adhere to global standards like ASME, ASTM, and ANSI. Built for high-pressure and high-temperature scenarios, Phanuphong’s weld neck flanges deliver exceptional strength, reliable sealing, and durability. Supported by cutting-edge manufacturing processes and rigorous quality checks, Phanuphong caters to a diverse array of industries, including oil & gas, petrochemical, power generation, and construction, ensuring trustworthy flange solutions for both local and international markets.
When it comes to the composition and mechanical properties of Phanuphong’s Carbon Steel Weld Neck Flanges, they are generally crafted from carbon steel grades such as ASTM A105 or A350 LF2. The blend includes carbon (up to 0.35%), manganese (0.6–1.05%), along with phosphorus, sulfur, and a hint of silicon. These flanges undergo forging and heat treatment to boost their strength and toughness. Their mechanical properties showcase a tensile strength ranging from 485 to 655 MPa and a minimum yield strength of 250 MPa. The weld neck design is specifically engineered to ensure optimal stress distribution and resistance to fatigue, making these flanges perfect for high-pressure piping systems in demanding industrial settings.
| Specification | ASTM A105 / ASME SA105 |
|---|---|
| Size Chart | 1/2″ (15 NB) to 48″ (1200NB) DN10~DN5000 |
| Standards | ANSI/ASME B16.5, B16.47 Series A & B, B16.48, BS4504, BS 10, EN-1092, DIN, ANSI Flanges, ASME Flanges, BS Flanges, DIN Flanges, EN Flanges, GOST Flange, ASME/ANSI B16.5/16.36/16.47A/16.47B, MSS S44, ISO70051, JISB2220, BS1560-3.1, API7S-15, API7S-43, API605, EN1092 |
| Pressure Rating ANSI | Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS |
| Pressure Calculation in DIN | 6Bar 10Bar 16Bar 25Bar 40Bar / PN6 PN10 PN16 PN25 PN40, PN64 |
| UNI | 6Bar 10Bar 16Bar 25Bar 40Bar |
| EN | 6Bar 10Bar 16Bar 25Bar 40Bar |
| Coating | Oil Black Paint, Anti-rust Paint, Zinc Plated, Yellow Transparent, Cold and Hot Dip Galvanized |
| Test Certificates | EN 10204/3.1B Raw Materials Certificate 100% Radiography Test Report Third Party Inspection Report, etc |
| Production Technique | Forged, Heat treated and machined |
| Connect Type/ Flange Face Type | Raised Face (RF), Ring Type Joint (RTJ), Flat Face (FF), Large Male-Female (LMF), Lap-Joint Face (LJF), Small Male-Female (SMF), Small Tongue, Large Tongue & Groove, Groove |
| Special design | As per your drawing AS, ANSI, BS, DIN and JIS 15 NB (1/2″) to 200 NB (8″) Equal and Reducing Configurations |
| Test | Direct-reading Spectrograph, Hydrostatic testing machine, X-ray detector, UI trasonic flaw detector, Magnetic particle detector |
| Equipment | Press machine, Bending machine, Pushing Machine, electric bevelling machine, Sand-blasting machine etc |
| Manufacturer of | ANSI DIN, GOST, JIS, UNI, BS, AS2129, AWWA, EN, SABS, NFE etc. BS Flange, EN Flange, API 6A Flange, ANSI Flange, ASME Flange, DIN Flange, EN1092-1 Flange, UNI Flange, JIS/ KS Flange, BS4504 Flange, GB Flange, AWWA C207 Flange, GOST Flange, PSI Flange B.S: BS4504 , BS3293, BS1560, BS10 AS 2129: Table D; Table E; Table H ANSI B16.5, ANSI B16.47 Series A & B, MSS SP44, ASA, API-605, AWWA, Custom Drawings ANSI : ANSI B16.5, ANSI B16.47(API605), MSS SP44, ANSI B16.36, ANSI B16.48 ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48 American standard (ANSI) German (DIN) British standard (BS) DIN: DIN 2527, DIN 2566, DIN 2573, DIN 2576, DIN 2641, DIN 2642, DIN 2655, DIN 2656, DIN 2627, DIN 2628, DIN 2629, DIN 2631, DIN 2632, DIN 2633, DIN 2634, DIN 2635, DIN 2636, DIN 2637, DIN 2638 ASTM A105 Carbon Steel F42 Carbon Steel Flanges The other standard: AWWA C207; EN1092-1, GOST12820, JIS B2220; KS B1503, SABS1123; NFE29203; UNI2276 |
| Grades | Carbon Steel F65, A36, F42, F52, IS2062, F60, LF2, F70, F80, F56, A105 |
| Material Test Certificates (MTC) as per EN 10204 3.1 and EN 10204 3.2, Test Certificates certifying NACE MR0103, NACE MR0175 | |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
| ASME/ANSI B 16.5 | Welding Neck Flange |
| PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
| ASME/ANSI B 16.47 | Blind Flange [Series A & B],Welding Neck Flange |
| PRESSURE CLASS | 75, 150, 300, 400, 600, 900 |
| ASME/ANSI B 16.36 | Welding Neck Flange |
| PRESSURE CLASS | 300, 400, 600, 900, 1500, 2500 |
| PRESSURE CLASS | PN 2.5 TO PN 40 |
| BS 4504[PART 1] | Hubbed Slip-On |
| PRESSURE CLASS | PN 2.5 TO PN 400 |
| BS 1560 BOSS | Hubbed Slip-On Hubbed Threaded |
| PRESSURE CLASS | 150, 300, 400, 600, 900, 1500, 2500 |
| BS10 | Plate Slip-On Flange, Slip-On Boss Flange |
| TABLE | D, E, F, H |
| DIN FLANGES | DIN 2527, 2566, 2573, 2576, 2641,2642, 2655, 2656, 2627, 2628, 2629, 2631, 2632, 2633, 2634, 2635, 2636, 2637,2638, 2673 |
| PRESSURE CLASS | PN 6 TO PN 100 |
Phanuphong Steel’s Carbon Steel Weld Neck Flanges find their place in high-stress applications where robust strength and leak-proof connections are a must. They are commonly used in oil & gas pipelines, refineries, chemical plants, and power generation facilities, making them ideal for systems that deal with high pressure, temperature, or hazardous fluids. The long tapered hub not only reinforces the flange but also minimizes stress concentration at its base, making it a reliable choice for critical joints in process piping and steam lines.
Phanuphong Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Bangkok, Thailand.
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