Cold-Climate Sealing Security: Haihao Group Delivers Class 300 A350 LF2 LM Flanges to Russia
Operating processing facilities in northern Eurasia requires specialized piping components engineered to handle severe sub-zero thermal stress without compromise. Large pressure fluctuations combined with arctic ambient conditions place heavy demands on flange sealing faces and weld hub transitions. Fulfilling a custom procurement contract for an industrial energy client in Russia, Haihao Group has manufactured, non-destructively tested, precision-machined, and shipped a targeted consignment of low-temperature forged carbon steel weld neck flanges.
Forged strictly in accordance with ASME B16.5 standards, this shipment includes 1” and 10” Class 300 weld neck flanges fabricated from normalized ASTM A350 Grade LF2 Class 1 steel. Every flange features a precision Large Male (LM) facing paired with specific bore schedules designed to match exact line pipe dimensions.
ASME B16.5 ASTM A350 LF2 Class 300 Large Male face weld neck flange for low temperature Russian pipeline produced by Haihao Group
Delivery Technical Specifications & Matching Pipe Dimensions
To ensure zero internal flow disruption and optimal stress distribution across the welded hub, the bore dimensions were custom-machined to match the client’s seamless line pipe schedule:
| Nominal Flange Size (NPS / DN) | Pressure Class | Flange Face Configuration | Matching Line Pipe Dimensions (OD × WT) | Material Specification | Applicable Manufacturing Standard |
| DN25 (1”） | Class 300 | Large Male (LM) Face | 33.4 mm x 3.38 mm (SCH 40) | ASTM A350 LF2 Class 1 | ASME B16.5 |
| DN250 (10”) | Class 300 | Large Male (LM) Face | 273.0 mm x 9.27 mm} (SCH 40 / STD) | ASTM A350 LF2 Class 1 | ASME B16.5 |
Engineering Advantages: Large Male Facing & Low-Temp Forging Metallurgy
Procuring specialty low-temperature forgings through an established ASME B16.5 A350 LF2 flange exporter ensures that critical flanged joints maintain reliable gasket retention and structural toughness under intense freeze-thaw cycles.
Haihao Group incorporated several critical engineering measures into this delivery:
Large Male (LM) Facing Performance: Unlike standard Raised Face (RF) flanges, the Large Male (LM) facing works as part of a Male-and-Female (M&F) joint configuration. The raised section retains the gasket within a semi-enclosed groove, preventing gasket blowout under sudden line pressure surges and maintaining a tight seal in cold Russian operating conditions.
Low-Temperature Impact Ductility: All A350 LF2 Class 1 forgings underwent normalizing heat treatment to refine the steel grain structure. Verified through Charpy V-notch testing at -46°C (-50°F), the metal maintains high notch toughness and resists brittle fracture during sub-zero operational shutdowns.
Exact Matching Pipe Bore Alignment: By machining the weld neck hub ID to match 33.4 mm x 3.38 mm for 1” and 273.0 mm x 9.27 mm for 10”, the transition from pipe to flange hub is completely flush. This minimizes internal flow turbulence, prevents localized erosion, and eliminates pockets where corrosive condensation could accumulate.
Precision Machining, Inspection & Export Protection
To reinforce our reputation as a trusted ASME B16.5 A350 LF2 flange exporter, every forging was audited through strict quality controls prior to dispatch:
Facing & Groove Dimensional Inspection: The height, diameter, and phonographic surface finish (Ra = 3.2–6.3μm) of the Large Male face were verified using digital profile gauges to ensure gasket compatibility.
Volumetric & Surface NDE: Magnetic Particle Examination (MT) was conducted across the hub taper and weld end, while Ultrasonic Testing (UT) confirmed zero internal forging voids or laminations.
Bevel End Protection & Rust Preservation: Butt-weld ends were machined with 37.5° bevels for field welding. All machined faces were treated with a heavy-duty anti-corrosion coating and capped with plastic end covers to safeguard against damage during transit to Russia.
Complete Quality Traceability: Delivered with EN 10204 Type 3.1 Material Test Certificates detailing chemical composition heat logs, mechanical tensile values, Charpy impact test data at -46°C, and heat treatment charts.
Relying on a professional ASME B16.5 A350 LF2 flange exporter streamlines site fit-up, speeds up line welding, and protects severe-environment processing plants from leakages.
Partner with Haihao Group for Russian Industrial Projects
In need of high-integrity ASME B16.5 low-temperature flanges, Class 300 Large Male/Female forgings, or custom-bored A350 LF2 weld neck components for your energy assets in Russia and the CIS region? Partner with an experienced ASME B16.5 A350 LF2 flange exporter. Contact the Haihao Group commercial sales engineering team today for technical support and rapid competitive quotes.