Langfang Yongsheng Industrial Products Co., Ltd.
+86-13373362088

Top Flanges Supplier in China

As a leading manufacturer based in China, we are dedicated to engineering and producing high-performance forged steel flanges that set the industry standard. Our commitment to quality is absolute, with every flange meticulously crafted to meet stringent international specifications like ASME and EN. This guarantees unmatched reliability and safety for your critical systems. Partner with one of the most dependable flange suppliers and build your projects on a foundation of strength and precision.

Flanges
Decades of Expertise
Certified Quality Assurance
Advanced Forging & Machining
Global Standards Compliance
Flanges

What is a Flange?

A flange is a forged or cast ring, typically made of steel, that serves as a critical component for connecting pipes, valves, pumps, and other equipment to construct a comprehensive piping system. Unlike permanent welded joints, a flanged connection offers the significant advantage of easy assembly and disassembly. This modularity is essential for systems requiring periodic maintenance, inspection, or modification, saving significant time and labor. The joint is formed when two flanges are bolted together with a gasket compressed between them, creating a robust, leak-proof seal capable of withstanding specified pressure and temperature conditions. Flanges are manufactured in a wide array of materials and designs, each governed by strict international standards to ensure the integrity of the system.

What is a Flange Used For?

  • Equipment Connection: Provides a secure, serviceable joint for connecting pipes to critical equipment like pumps, valves, and vessels.

  • System Maintenance: Facilitates easy access to pipelines for routine inspection, cleaning, and repair, minimizing operational downtime.

  • Pipe-to-Pipe Joining: Creates strong mechanical joints between pipe sections, essential in areas where welding is hazardous or not feasible.

  • Line Termination & Isolation: Allows for the secure termination or isolation of a pipeline using a blind flange for pressure testing or future expansion.

Flanges

Why Choose Our Flanges?

Our manufacturing philosophy is centered on quality and precision. We combine controlled forging processes with advanced CNC machining to produce flanges that consistently meet strict industry standards for strength, accuracy, and long-term operational reliability.

Superior Material Strength

Our forging process enhances the metallurgical properties of the steel, resulting in flanges with superior strength and resistance to high pressure and temperature.

Precision Machining

Utilizing advanced CNC equipment, we guarantee precise dimensions and a perfect sealing surface on every flange, ensuring leak-free performance.

Exceptional Durability

From carbon and alloy steel to stainless flanges and nickel alloys, our products are built to withstand corrosion and wear for a long service life.

Customizable Flange Design

We offer tailored solutions based on your specific requirements, including custom dimensions, materials, and compliance with your unique flange design specifications.

What Is The Difference Between Forged And Cast Flanges?

How To Choose The Right Flange For Your Application?

Explore Our Types of Flanges

Plate flat welding flange

Plate flat welding flange

Designed to slide over the pipe, this flange is secured by two fillet welds, one on the exterior and one on the interior. It is a cost-effective and easy-to-align solution, commonly used for low-pressure and non-critical applications.

Socket Weld Flange Drain

Socket flange

Featuring a recessed socket for the pipe to rest in, this flange is joined with a single external fillet weld. This design creates a smooth bore and is ideal for smaller diameter pipes in high-pressure systems where leak resistance is crucial.

Neck flat welding flange

Neck flat welding flange

Also known as a Weld Neck flange, it features a tapered hub that is butt-welded to the pipe. This transfers stress from the flange to the pipe itself, providing superior strength for high-pressure, high-temperature, or volatile applications.

Butt welding flange

Butt welding flange

This flange (typically a Weld Neck type) is defined by its connection method. The beveled end is precisely matched to the pipe's bevel, creating a strong, continuous weld that becomes an integral part of the piping system, ensuring maximum structural integrity.

Threaded (Screwed) Flange

Threaded (Screwed) Flanges

This flange has internal threads that screw directly onto a threaded pipe, eliminating the need for welding. It is typically used for smaller pipe sizes in low-pressure service and in environments where welding is hazardous or impractical.

Blind Flanges

Blind Flanges

A solid disc with bolt holes, the blind flange is used to seal the end of a piping system or a pressure vessel opening. It provides easy access for future modifications or maintenance and is essential for hydrostatic pressure testing of a system.

Loose sleeve flange

Loose sleeve flange

A two-piece assembly consisting of a stub end welded to the pipe and a backing flange that rotates freely. This design simplifies bolt alignment and is perfect for systems that require frequent disassembly for maintenance or inspection.

Integral flange

Integral flange

An integral flange is not welded or attached but is forged or cast as a single unit with the component, such as a valve body or vessel nozzle. This one-piece construction offers the highest strength and reliability for severe service conditions.

Flange Size Specifications Chart: ASME B16.5 Class 150

NPS (inch)Flange OD (mm)Min. Thickness (mm)Raised Face Dia. (mm)No. of BoltsBolt Circle Dia. (mm)Bolt Hole Dia. (mm)
1/2"88.911.234.9460.315.9
1"108.014.350.8479.415.9
2"152.419.192.14120.719.1
3"190.523.9127.04152.419.1
4"228.623.9157.28190.519.1
6"279.425.4215.98241.322.2
8"342.928.6269.98298.522.2
10"406.430.2323.912362.025.4
12"482.631.8381.012431.825.4
The data above is for reference purposes. We manufacture a full range of flanges covering all schedules and pressure classes (150, 300, 600, 900, 1500, 2500) and comply with various international standards including EN 1092-1, DIN, BS, and JIS. For complete technical data sheets or custom requirements, please contact our engineering team.

Key Application Industries of Flanges

Oil & Gas / Petrochemical

Used for joining high-pressure pipelines, process vessels, and valves in upstream, midstream, and downstream operations.

Power Generation

Connects high-pressure steam lines, boiler systems, and turbine equipment in fossil fuel, nuclear, and renewable energy plants.

Shipbuilding & Marine

Applied in marine piping for ballast water, engine room cooling, and fuel systems, resisting saltwater corrosion and vibration.

Machinery & Metallurgy

Integral to hydraulic circuits, heavy machinery, and processing equipment in industrial manufacturing and metallurgical plants.

Why Choose Our Flanges?

  • Direct Manufacturing Expertise: As a manufacturer since 1983, we control the process from raw material forging to CNC machining, ensuring consistent product quality.

  • Comprehensive Quality Control: Our ISO 9000 certified system ensures full traceability, with in-house testing for mechanical properties and dimensional accuracy.

  • Broad Material & Standard Compliance: We produce flanges in carbon, alloy, and stainless steel, adhering to major international standards like ASME, EN, and DIN.

  • Custom Engineering Solutions: Our technical team delivers tailored solutions, manufacturing custom flanges from your specific drawings for unique project needs.

  • Proven Reliability & Service: With decades of experience, we are committed to delivering dependable products and professional service to support all your project needs.

Flanges

What Our Client Says

Understand from our clients what they say about doing business with us and the unique value addition we provide.

"We required a series of custom stainless flanges based on our own technical drawings. Their engineering team was highly competent, providing valuable feedback and delivering a final product that matched our specifications with exceptional precision. Their custom capabilities are first-class."
Markus Schmidt
Head of Engineering
"As an international buyer, clear communication is just as important as product quality. Their sales team was incredibly responsive and professional, handling all our technical queries and shipping arrangements efficiently. We are very satisfied with both the product and the service."
Customer reviews
Ahmed Al-Jamil
Project Manager

Comprehensive Guide to Flanges

Flanges

Latest Blog Posts

Maintain Inventiveness by Following The Blog for the Latest Best Practices, Techniques, Innovations, and Insights in the Field.

What are Flange Bolts Used For?

From large-scale construction projects to intricate machinery systems across every industry, flange bolts play a crucial role as heavy-duty fastening solutions. Unlike regular bolts, they feature an integrated washer-type...

Partner With a Trusted Flange Manufacturer

With decades of forging experience and a commitment to quality, we are ready to be your reliable partner for all your flange requirements. From standard orders to complex custom designs, our team is here to provide the expertise and products you need to succeed. Contact us today to discuss your project.

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