Blind Flange

Blind Flange

A flange is widely utilized in several systems to join pipes, tubes, valves, and other modules across various piping systems. These components provide support to the pipe through various high-pressure and elevated temperature systems. There are different types of flanges each of them has a unique function that is, suited for particular applications.

A flange, which doesn’t have a hub or a face, can be termed as a blind flange. They are components, which are used to eliminate the flow within the system. The items can also be used as a barrier for pipe repairs or provide time to make modifications in the existing pipe design. The modules have to be extremely strong and possess good corrosion resistance as they are exposed to corrosive media all the time. They can be easily welded or bolted. If they are bolted they, allow for a passage that enables the operator to inspect and maintain the entire system.

What is a high Hub blind flange?

The component is made of a circular shape having no hub or a boring center. This high hub enables it to create a positive closure to the pipeline. They don’t require any machining and are very heavy. The items are available in various sizes and material types according to their requirements.

Do blind flanges have raised face?

There are two types within this component range namely raised face and a flat-faced. The RF module is the most commonly used item between the two. It can been seen above the bolting circle where the gasket will be placed. The raised face helps in putting pressure on the seal to make it strong and impenetrable. They can be utilized in several low and high-pressure systems across several industries.

What is a paddle blind?

A paddle blind is a part of a spectacle blind, which is installed between two flanges as a safety device. The blind paddle is a solid device with a solid metal surface. These components are fitted in systems, which don’t require constant maintenance. These paddles are used as devices that temporarily block the flow to fix any issues within the system. Once the maintenance is complete, a paddle spacer is installed to the assembly. This enables the system to continue its operations smoothly.

The function

The main function of these flanges is to eliminate the flow within the entire system. They facilitate repairs and new fittings to be installed on the line with ease. The items are also employed to check the pressures within the piping network. They provide an opening that helps in checking the integrity and maintain the entire component in an evenly order.


All flanges and piping instruments are carefully produced following several industrial standards. Each of these standards possesses its own identity and requirement, which separates it from the other. Both ANSI and ASME flanges follow different amendments and principles.

  • The flanges manufactured by American National Standards Institute are developed by organizations, while the American Society of Mechanical Engineers flanges is based on abbreviations and codes from several mechanical devices.
  • ANSI modules are designed using 9500 approximate standards, while the other is designed using standards of 600 codes based on different mechanical units.
  • ASME flanges work to improve and find an existing solution to problems while the other is aimed at improving the strength of their country in the global markets.

What is a blind tapped flange?

A bind tapped flange is made with an NPT tapped threaded hole in the middle. It has ½ npt tapped thread comprising of special threads and holes allowing it to connect different types of fittings.

How do I know what size blind flange I need?

The flanges of this grade are designed to match the specific bolt hold measurements of several other devices. This makes it very essential to choose the appropriate size of components able to meet the material specifications, dimensions, and pressure classes.

The most commonly used bind flange material is steel and stainless steel. Both these elements can be used in several conditions. However, stainless steel is slightly better due to its superior corrosion and oxidation resistance properties along with enhanced strength characteristics.

The items are available in the same specifications as other flanges but, they are slightly thicker. It is thereby important to measure the outer diameter, bolt hole circle, diameter, and thickness to get the right size. The thickness of the flange will also be very critical in selecting the right module. Apart from this, each flange has specific pressure ratings. Understanding and selecting a product range with the correct class is of utmost importance.


These components are used to terminate the flow of fluids or gases within the system. They act as a barrier that allows new structures to be built at the same time they help in performing fixes on the system.

Ramesh Steel Corporation