Overview
When pipe diameters exceed 24 inches (NPS 24 / DN 600), flange design moves from ASME B16.5 into ASME B16.47 territory. Large diameter flanges — spanning NPS 26 through NPS 60 — present unique engineering challenges: ring rolling limitations, bolting torque distribution, RTJ groove machining precision, and multi-ton shipping logistics.
JIAJI FORGING operates ring rolling mills capable of producing seamless forged rings up to 2,200mm OD, enabling us to manufacture ASME B16.47 flanges without circumferential welds. This cluster covers the full lifecycle of large diameter flanges:
MSS SP-44 vs API 605 — Series A has larger OD, thicker, heavier, and uses fewer larger bolts. Not interchangeable!
Seamless forged rings with circumferential grain flow. How ring rolling works and why it matters for large flanges.
Precision groove machining for metal-to-metal seals. Octagonal vs oval R-type ring gaskets per ASME B16.20.
Multi-ton flange logistics: ISPM 15 wooden crates, container vs flat-rack vs break-bulk, and export documentation.
Articles in This Cluster
ASME B16.47 Series A vs Series B: Large Diameter Flange Comparison
MSS SP-44 (Series A) vs API 605 (Series B): dimensional differences, bolt count, thickness, weight, and interchangeability for NPS 26-60.
Read Full Guide →Large Diameter Weld Neck Flanges: NPS 26-60 Design Guide
Ring-rolled WN flanges for large bore piping. Hub dimensions, welding end preparation, and weight calculation for NPS 26 through NPS 60.
Read Full Guide →Large Diameter Blind Flanges: Design & Pressure Calculation
Blind flange thickness calculation per ASME B31.3 304.5.3. Material selection, stiffened vs un-stiffened designs, and handling considerations.
Read Full Guide →RTJ Groove Design for Large Diameter Flanges
Ring Type Joint groove dimensions for ASME B16.47 flanges. Octagonal vs oval ring gaskets, hardness requirements, and machining tolerances.
Read Full Guide →Shipping & Logistics for Oversized Forged Flanges
Container loading, break-bulk shipping, weight limits, crating requirements, and documentation for flanges over 2 tons. Export packaging standards.
Read Full Guide →Need Expert Guidance on Large Diameter Flanges?
JIAJI FORGING's engineering team brings 15+ years of experience in forged flange design, material selection, and international standards compliance.