Explore our factory-direct precision forged piping solutions engineered for high-pressure, severe-corrosion, and critical industrial fluid systems worldwide.
A Stub End flange—frequently paired with a backing Lap Joint Flange—is a two-piece piping assembly designed to optimize installation speed, drastically lower material expenditure in high-alloy systems, and eliminate bolt-hole alignment issues in complex piping spools.
Manufactured to mate specifically with standard Lap Joint Flanges. Type A features a machined lap face with a smooth, radiused outer corner that perfectly mirrors the inside radius of the lap joint backing flange, ensuring uniform pressure loading across the gasket surface.
Designed to be utilized with standard Slip-On Flanges serving as backing flanges. Type B possesses a smaller outside radius, preventing interference with the slip-on flange’s internal chamfer while delivering reliable seal dynamics in medium-pressure fluid systems.
Fabricated from seamless or welded pipe sections or pressed plate with a flared lap. Type C provides a versatile, cost-efficient solution suitable for low-pressure, light-duty commercial piping, water treatment facilities, and HVAC systems.
Headquartered in Dingxiang County, Shanxi—recognized globally as China's Hometown of Forging—our integrated mill provides complete metallurgical control from raw billet to finished CNC flange machining.
Full compliance with MSS SP-43 (for light-weight corrosion-resistant fittings) and ASME B16.9 (factory-made wrought butt-welding fittings) in both Short Pattern and Long Pattern configurations.
Every heat of steel undergoes positive material identification (PMI), ultrasonic flaw detection (UT), magnetic particle testing (MT), dynamic impact testing at sub-zero temperatures, and hydrostatic evaluation.
Direct factory exporting to over 40 countries across North America, the European Union, the Middle East, Southeast Asia, and South America, maintaining 100% project compliance.
For international procurement directors, EPC contractors, and stocking distributors, sourcing Stub End flanges directly from Shanxi Yuxin Casting & Forging Co., Ltd. provides distinct structural, logistical, and technical advantages.
Located in the heart of Dingxiang's industrial forging cluster, Yuxin maintains strategic partnerships with top-tier Chinese steel mills (TISCO, Baosteel, Shougang). Bulk procurement of raw carbon, alloy, and stainless billets allows us to buffer against global steel market volatility, delivering stable, highly competitive direct factory pricing to international buyers.
Unlike trading agencies or regional machine shops that outsource forging, every step of our manufacturing—billet cutting, gas furnace heating, open/closed die forging, hydraulic ring rolling, solution annealing heat treatment, CNC flange face serration, and automatic bolt drilling—takes place under one roof with strict quality controls.
Our products are engineered to fulfill stringent global standards: EU Pressure Equipment Directive (PED 2014/68/EU), AD 2000-Merkblatt W0, German TUV certification, and NACE MR0175/ISO 15156 for sour oilfield service. Mill Test Certificates (MTC) conforming to EN 10204 3.1 are supplied with every order, detailing full chemical analysis and mechanical values.
Stub end sealing faces are precision-machined and protected with rust-preventive varnish, plastic end caps, and heavy-duty ISPM-15 compliant fumigation-free wooden cases or steel-framed crates. Custom branding, heat number hard-stamping, color-coding by alloy grade, and barcoded inventory labels are standard services for OEM distributors.
Compare standard dimensional ranges, material grades, and international pressure class mappings engineered at Shanxi Yuxin Casting & Forging Co., Ltd.
| Standard Ref. | Nominal Size (NPS / DN) | Wall Thickness / Schedules | Common Material Grades | Facing & Serration Finish |
|---|---|---|---|---|
| MSS SP-43 (Type A/B) | 1/2" to 24" (DN15 - DN600) | Sch 5S, Sch 10S, Sch 40S | ASTM A403 WP304/304L, WP316/316L, WP321 | Smooth Finish (125-250 AARH), Concentric/Spiral Serrated |
| ASME B16.9 (Long/Short) | 1/2" to 48" (DN15 - DN1200) | Sch 40, Sch 80, Sch 160, XXS | ASTM A234 WPB, A420 WPL6, A860 WPHY52/60/65 | Stock Finish (250-500 AARH), Machined Bevel to ASME B16.25 |
| EN 1092-1 Type 33 | DN15 to DN1000 | PN6, PN10, PN16, PN25, PN40 | P245GH, P280GH, 1.4301, 1.4404, 1.4462 (Duplex) | Type A Flat Face, Type B1 Raised Face (Ra 3.2 - 12.5 µm) |
| Custom OEM Drawings | Up to 120" (DN3000) | Non-Standard Custom Thickness | Inconel 625, Hastelloy C276, Titanium Gr 2, Monel 400 | RTJ Ring Groove, Male-Female, Tongue & Groove, Custom O-ring |
From extreme marine environments to high-purity pharmaceutical piping, Stub End flanges provide essential structural advantages.
High-salinity seawater systems require Super Duplex (2507) or Titanium stub ends welded to pipe spools. Pairing them with epoxy-coated carbon steel backing flanges protects against severe pit corrosion while keeping vessel fabrication budgets balanced.
Aggressive acid lines demand Hastelloy C276 or 316L wetted surfaces. Stub end assemblies facilitate fast disassembly during scheduled plant turnarounds for cleaning, inspection, or rapid pipe section replacement.
Modular skid manufacturers rely on the rotational flexibility of lap joint stub ends to assemble complex pre-fabricated piping modules in tight spatial envelopes, eliminating field re-welding due to bolt-hole misalignment.
Gain immediate insights into technical standards, material matching, tolerance limits, and procurement processes for custom Stub End flanges.
Discover our wide spectrum of complementary forged pipe flanges, tube sheets, and specialized fittings manufactured to international standards.
Work directly with Shanxi Yuxin Casting & Forging Co., Ltd.'s metallurgical engineering team. Send us your drawings, standard specifications, or bill of materials for a comprehensive technical quote within 24 hours.
