Haihao Group Supplies LF2 Forged Steel Flanges to Kazakhstan Oil & Gas Project
Haihao Group has completed another international delivery, providing a set of ASTM A350 LF2 forged steel flanges to a customer in Kazakhstan. The order contains welding neck flanges, blind flanges, and RTJ-type welding neck flanges, all engineered for low-temperature and sour-gas environments.
Every flange is produced in compliance with ASME B16.5 and supplied with EN 10204 3.1 inspection certificates, ensuring full material traceability and quality assurance.
Overview of Supplied Flange Types
● 3″ Class 150 Welding Neck Flange, Raised Face (RF)
These LF2 low-temperature welding neck flanges feature a raised-face sealing surface and hub dimensions produced to SCH40. The controlled surface roughness of 125–250 µin ensures reliable gasket performance.
Designed for pipelines that require both low-temperature resistance and sour-service capability, this ASME B16.5 Class 150 RF flange is widely used in upstream and midstream facilities.
Blind flange ASTM A350 LF2 Class-1 raised face CL150
● 1½” Class 150 Blind Flange, RF Type
The shipment also includes ASTM A350 LF2 blind flanges used for pipeline closure, pressure testing, and system isolation.
Their raised-face design provides stable sealing contact, while LF2 carbon steel ensures excellent toughness in cold environments.
This sour-service blind flange meets the requirements of NACE MR0175, making it suitable for H₂S-rich production fields.
● 12″ Class 600 Welding Neck Flange, RTJ Facing
The order’s largest component is the 12-inch, Class 600 RTJ welding neck flange, manufactured to SCH80 hub thickness (17.48 mm).
The ring-type joint (RTJ) groove, machined to 1.6 μm (63 µin) surface roughness, delivers premium sealing in high-pressure, high-temperature applications.
Such high-pressure RTJ welding neck flanges are commonly used in demanding oil and gas installations where reliability is critical.
Material & Compliance
All the supplied flanges are produced from ASTM A350 Grade LF2 Class 1, known for its outstanding performance in low-temperature service.
Compliance Summary:
- Material grade: ASTM A350 LF2 CL1
- Standard: ASME B16.5
- Service condition: Sour-gas pipelines
- NACE requirement: MR0175 / MR 01-75 compliant
- Certification: EN 10204 Type 3.1
These specifications make the flanges suitable for pipelines transporting hydrocarbons containing H₂S, CO₂, and other corrosive compounds.
Supporting Kazakhstan’s Harsh Operating Conditions
Kazakhstan’s oil and gas sector operates in environments where winters are severe and sour-gas corrosion poses significant risk.
Haihao Group’s LF2 carbon steel flanges offer the required mechanical strength, impact resistance, and sour-service durability to support long-term operation in such conditions.
From forging to machining to quality inspection, each flange undergoes strict procedures to meet the expectations of international energy and construction companies.