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Comprehensive Guide to Flanges: Exploring Elite Piping’s High-Quality Solutions (Part 1)
Elite Piping Manufacture Co., Ltd is a renowned manufacturer of flanges and supplier of pipe fittings and line pipes. Located in Bazhou City, Hebei Province, our facility spans an impressive 100,000 square meters and boasts a registered capital of 50 million yuan, with capital assets amounting to 320 million yuan. Our strong technical force is supported by 380 employees, including 122 professionals, 16 senior engineers, and 28 engineers. We are equipped with 280 advanced processing machinery, capable of producing flanges according to international standards, including ANSI, ISO, API, JIS, DIN, BS, MSS, and GOST, as well as non-standard flanges customized to technical drawings.
Our dedication to quality is reflected in our choice of materials: Carbon Steel, Alloy Steel, Special Alloy, Stainless Steel, Duplex, and Super Duplex. These materials ensure that our products are suitable for a variety of industries, such as Oil & Gas, Power Plants, Fertilizers, Petrochemicals, Metallurgy, and Shipbuilding. Over the years, we have built an enviable reputation based on our commitment to quality, exporting our products to more than 25 countries worldwide.
In this article, we will delve into the details of six essential types of flanges, showcasing the quality and innovation that Elite Piping brings to the market. This is the first part of our comprehensive series on flanges, starting with the Weld Neck Flange, Anchor Flange, Orifice Flange, Compact Flange, Spectacles Blind Flange, and Reducing Flange.
Weld Neck Flange
A Weld Neck Flange, also known as a high-hub flange or tapered hub flange, is a type of flange designed to provide a secure connection in high-stress environments. There are two main designs: the regular type, which is used with pipes, and the long type, which is unsuitable for pipes and typically used in process plants. A weld neck flange consists of a circular fitting with a protruding rim around its circumference. Generally machined from a forging, these flanges are typically butt-welded to a pipe. The rim has a series of drilled holes that allow the flange to be affixed to another flange with bolts.
Weld Neck Flanges are ideal for use in hostile environments with extremes of temperature, pressure, or other sources of stress. Their design allows them to handle pressures up to 5,000 psi. The resilience of this type of flange is achieved by sharing environmental stress with the pipe to which it is welded. This makes it a preferred choice for critical applications where safety and reliability are paramount.
The Weld Neck Flange is an essential component for high-stress applications. Its robust design and ability to withstand extreme conditions make it a reliable choice for various industries.
Anchor Flange
An Anchor Flange is a device installed on a pipeline to counteract axial movement, preventing the pipeline from moving. Once the flange is welded to the pipe, it is usually anchored to a concrete foundation. The primary function of the anchor flange is to prevent axial movement, which is crucial when the pipeline crosses a bridge or river. Over long distances, pipes carrying large volumes of liquid tend to sink, making anchor flanges vital for maintaining the pipeline’s position.
Anchor flanges are commonly used in large diameter, high-pressure, and long-distance oil and gas pipelines. They act as important supporting elements, usually placed underground or buried. One of the common characteristics of a metal pipeline is the inherent movement caused by fluid flow and temperature changes. When a pipeline makes a sharp turn, the fluid flow attempts to push the pipe in the direction of the flow. By placing an anchor flange on the pipeline and securing it in place by locking it into a concrete pillar buried deep in the ground, the forces pushing against the pipe are transferred to the earth.
Anchor Flanges are essential for maintaining the stability and integrity of pipelines, especially in challenging environments where axial movement must be controlled.
Orifice Flange
Of the flanges discussed, the Orifice Flange is the only one that performs a specific function. Its primary function is to measure the rate of flow of the commodity through the piping system. Orifice flanges are easily recognizable due to the hole drilled through the face of the flange perpendicular to the pipe. They also have an additional set of bolts called jack screws, used to help separate the flanges for inspection or replacement of the orifice plate. The orifice flange is a single component of the orifice flange union assembly, which includes two orifice flanges, an orifice plate, bolts, nuts, jack screws, and two gaskets.
The orifice flange union measures the pressure drop through the orifice plate. The length of pipe where orifice flanges are installed and where measurements are recorded is known as a meter run. The orifice plate, which resembles a large ring washer with a handle, is sandwiched between the orifice flanges. Valve taps are inserted into pressure holes, allowing for the attachment of field monitoring equipment for accurate measurements. Orifice flanges can be either weld neck, slip-on, or threaded. Weld neck and threaded orifice flanges are manufactured in 300# and larger pound ratings, while slip-on orifice flanges are only available as 300# raised face flanges.
Orifice Flanges are crucial for measuring flow rates in pipelines, ensuring accurate monitoring and control in various industrial applications.
Compact Flange
Compact Flanges are designed to be space-efficient while maintaining high performance. They transfer almost all bolt load through metal-to-metal full face-to-face contact between the flanges. Only a small fraction of the bolt load is used to energize the seal ring, solving the problem of flange rotation without the need for a flange hub. The transition from the flange ring to the flange neck is made using an elliptic transition, reducing local stress concentrations.
Compact flanges are ideal for high-pressure applications. They minimize the end cap area and hence the end cap pressure force trying to separate the flanges by placing the bolts closer to the inner bore. This reduces the warping moment the flange must carry, contributing to further reduced dimensions. A bevel angle of the flange face maximizes the compression load at the inner diameter of the flange, ensuring efficient sealing even with extreme tension load in the piping system.
Compact Flanges offer significant advantages in terms of space efficiency and performance, making them suitable for high-pressure environments.
Spectacles Blind Flange
Spectacles Blind Flanges are a combination of a paddle blank (spade or slip blind) and a paddle spacer (spacer ring). One surface provides total closure for the piping systems, while the other includes a ring matching the inside diameter of the connected piping. Connected using a small nose piece or tie bar, they resemble a pair of spectacles.
Spectacles Blind Flanges allow for complete closure or full operation of a piping system by rotating the flange as needed. They are typically installed for long-term use due to their simple operation and durable design. Installation involves inserting one of the flange bolts through the hole on the central tie bar, reinforced with gaskets between the flanges and spectacle blind. Common locations for installation include bypass lines, inlets and outlets of rotary or static equipment, and inlets and outlets of storage and processing vessels.
Spectacles Blind Flanges provide flexibility during maintenance and system operations, ensuring positive shutoff in case of valve degradation or failure.
Reducing Flange
Like the reducer fitting, the Reducing Flange is used to reduce the diameter of the pipe. It is frequently used in installations with limited space due to its shorter overall length compared to a weld neck flange and reducer-fitting configuration. However, the flow should travel from the smaller size to the larger to avoid severe turbulence.
Reducing flanges are crucial in situations where space is limited. The pound rating and flange type are included in the callout. The reducing flange maintains all the dimensional characteristics of the larger end size, except for the internal bore, which is manufactured to match the smaller pipe size. This ensures a smooth flow transition and minimizes turbulence.
Reducing Flanges are essential for space-constrained installations, providing an efficient solution for reducing pipe diameter.
Conclusion
In this first episode, we have explored six essential types of flanges: Weld Neck Flange, Anchor Flange, Orifice Flange, Compact Flange, Spectacles Blind Flange, and Reducing Flange. Each flange type offers unique advantages and applications, showcasing the quality and innovation that Elite Piping Manufacture Co., Ltd brings to the market.
Stay tuned for the next episode, where we will continue to explore more about our advanced piping solutions. Thank you for joining us, and for more information, visit our website or contact us today.