What Are Pipe Flanges
What Are Pipe Flanges? The Essential Connectors in Piping Systems
Flanges are critical components in industrial piping systems, serving as the connecting points that join pipes, valves, pumps, and other equipment. These circular or rectangular fittings with bolt holes ensure secure, leak-proof connections, making them indispensable in industries such as oil and gas, chemical processing, power generation, and shipbuilding.
Why Flanges Matter in Industry? Flanges enable modular assembly, maintenance flexibility, and system scalability. They are manufactured under strict standards (ASME, ANSI, DIN, BS4504,GOST33259,EN1092-1, JIS, AS) to ensure safety and durability. Leading flange manufacturers, such as Zhejiang Chengjiu Pipeline Co., Ltd. , provide high-quality products with certifications including ISO 9001 and CE&PED4.3 EN10204 TYPE3.1 approvals.
With advancements in materials (stainless steel,super duplex steel, special alloys, titanium) and smart manufacturing, flanges are evolving to meet extreme conditions in renewable energy and deep-sea exploration.
For more details on flange solutions, visit www.cncjflange.com or contact our engineering team.
Slip-On Plate Pipe Flanges are designed to slide over the pipe. The flange's inside diameter is slightly larger than the pipe's outside diameter, ensuring a snug yet easy fit. These flanges are secured to the pipe with fillet welds at both the top and bottom. Slip-on pipe flanges are categorized into two types: Ring Flanges and Hub Flanges. Both types slip over the pipe, but hub flanges feature a raised hub for added strength. Available in sizes ranging from ½" to 80", slip-on flanges comply with industry standards and are offered in all material grades and specifications. CNCJ Flanges supplies high-quality slip-on plate pipe flanges to meet diverse industrial needs.
SLIP ON HUB (BOSSED) FLANGE RAISED FACE / FLAT FACE
A Slip-On Flange with Hub, also known as a Raised Face Slip-On Flange, is a type of pipe flange designed for easy installation and alignment. It features a slightly raised face around the bore, which provides a sealing surface for gaskets. The hub, or neck, extends from the flange body, offering additional strength and support. This design allows the flange to be slipped over the pipe and then welded in place, both on the inside and outside, ensuring a secure and leak-proof connection. Commonly used in low-pressure applications, Slip-On Flanges with Hub are valued for their simplicity, cost-effectiveness, and ease of assembly, making them a popular choice in various industrial piping systems.
Weld neck flanges are designed for high-pressure applications, offering superior strength and stress distribution. The pipe is welded to the flange's neck, allowing stress to transfer smoothly from the flange to the pipe. This design minimizes high-stress concentration at the hub's base, enhancing durability. The flange's inside diameter is precision-machined to match the pipe's inner diameter, ensuring optimal flow and alignment. Available in sizes from ½" to 80", weld neck flanges meet industry standards across all material grades and specifications. CNCJ Flange supplies high-quality weld neck pipe flanges for demanding industrial applications.
BLIND FLANGE (BLANK FLANGE) RAISED FACE / FLAT FACE
Blind pipe flanges are sealing components designed to close off piping systems or pressure vessels, effectively preventing flow. Primarily used in high-pressure applications, they facilitate system testing and allow easy internal access for maintenance. Available in standard sizes ranging from 1/2" to 80", these flanges meet industry specifications. CNCJ offers a comprehensive selection of blind pipe flanges in all materials, sizes, and pressure ratings.
Lap Joint Pipe Flanges slide over the pipe and are primarily paired with Stub End Fittings. The pipe is welded to the Stub End, while the flange remains free to rotate, eliminating bolt hole misalignment issues. This design makes them ideal for applications requiring frequent disassembly.
Available in standard sizes from ½" to 24", Lap Joint Flanges follow published specifications. For sizes exceeding 24", they are manufactured to Slip-On dimensions. CNCJ Flange supplies Lap Joint Flanges in all material grades, specifications, and sizes.
THREADED (SCREWED)FLANGE (ANSI NPT, BSPT etc)
Threaded Pipe Flanges feature a tapered threaded bore, allowing them to mate with externally threaded pipes. Unlike slip-on flanges, they require no welding, making them ideal for small-diameter, high-pressure applications.
CNCJ Flange supplies threaded pipe flanges in all material grades, specifications, and sizes, ensuring compatibility with diverse piping requirements.
Socket Weld Pipe Flanges are designed for high-pressure applications in smaller pipe sizes. The installation process involves inserting the pipe into the flange's socket and applying a fillet weld around the top, creating a secure connection while maintaining a smooth bore for optimal fluid or gas flow.
CNCJ Flange offers a complete range of Socket Weld flanges, available in all standard material grades, specifications, and sizes to meet diverse industrial requirements.
