Carbon Steel Flange — Factory Direct Supplier | Huaxia-Steel
Carbon steel flanges are the connection points of pipelines, pressure vessels, and equipment. They provide a bolted, gasketed joint that is easy to assemble, inspect, and maintain. Huaxia-Steel supplies forged and plate carbon steel flanges in common pressure classes and facing types, directly from Chinese manufacturers with ASME, EN, and JIS certifications.
Product Overview
Our carbon steel flanges are produced by forging, machining, or plate cutting depending on size, pressure class, and standard. Forged flanges offer the best mechanical properties and are preferred for high-pressure and high-temperature service. Plate flanges are economical for low-pressure applications. We supply slip-on, weld neck, blind, threaded, socket weld, and lap joint types to match your piping specification.
Carbon Steel Flange Specifications
| Parameter | Range / Standard |
|---|---|
| Size | 1/2″ (DN15) to 80″ (DN2000) |
| Pressure class | Class 150, 300, 600, 900, 1500, 2500 |
| PN rating | PN6, PN10, PN16, PN25, PN40, PN63, PN100 |
| Standards | ASME B16.5, B16.47, EN 1092-1, JIS B2220, GOST, DIN |
| Facing | RF, FF, RTJ, TG |
| Surface finish | Black, galvanized, anti-rust oil |
| Coating | Black paint, yellow paint, epoxy, zinc primer |
Available Grades
| Grade | Standard | Common Application |
|---|---|---|
| A105 / A105N | ASTM A105 | High-pressure oil & gas piping |
| A350 LF2 / LF3 | ASTM A350 | Low-temperature service |
| A181 | ASTM A181 | General industrial flanges |
| A694 F52–F65 | ASTM A694 | High-yield pipeline service |
| Q235B | GB/T 700 | Water, air, low-pressure systems |
| 20# | GB/T 699 | General pressure piping |
| St37-2 / S235JR | DIN / EN | European structural piping |
Manufacturing Standards
We manufacture flanges according to ASME B16.5 for NPS 1/2 to 24, ASME B16.47 for large-diameter series, EN 1092-1 for European projects, and JIS B2220 for Japanese and Asian markets. Dimensional inspection, surface finish check, and pressure testing are performed before release. Material certificates and heat treatment records are available on request.
Applications
- Oil and gas pipelines and refineries
- Petrochemical and chemical plants
- Power generation and boiler systems
- Water treatment and desalination
- Shipbuilding and offshore platforms
- General industrial piping and HVAC
- Fire protection and sprinkler systems
Quality Assurance
Each flange is visually inspected for surface defects, dimensional deviations, and marking accuracy. Forged flanges are checked for grain flow and heat treatment hardness. We offer hydrostatic testing, PMI testing, UT, and MT inspection. For critical projects, EN 10204 3.2 certificates and third-party inspection by SGS or BV can be arranged.
Packaging and Shipping
Flanges are packed in wooden crates or pallets, separated by cardboard or rubber to protect facing surfaces. Bolts, nuts, and gaskets can be supplied as a kit. For long sea voyages, we apply VCI bags or anti-rust oil. Each package is labeled with size, rating, standard, heat number, and quantity for easy customs clearance and inventory management.
Why Buy Carbon Steel Flanges from Huaxia-Steel?
- Direct factory pricing on forged and plate flanges
- Full range of ASME, EN, JIS, and GOST standards
- Material certificates and heat treatment records
- Kit packaging with bolts, nuts, and gaskets available
- Third-party inspection and project documentation support
Request a Quote
Send us your flange specification: type, size, pressure class, standard, grade, quantity, and destination port. We will provide a factory-direct quotation with lead time and full documentation.
