What are blind pipe flanges? Despite the fact that these pipe flanges are incredibly important for a wide variety of piping systems, many remain unaware of exactly how they work and what makes them unique. With that in mind, we’re exploring below a quick guide to blind pipe flanges — what they are, how they function, and what needs to be understood before an order is made for these specific types of flanges.

What Makes Blind Pipe Flanges Different?

Blind pipe flanges are generally different from other types of weld fittings. This is because they do have the typical bolt holes around the perimeter, but they don’t have the typical hole that moves through the center of pipe flanges. This means that they block the flow of a pipeline, which allows simple access to the interior of the line when it has been closed and must be reopened.

They also are known for their durability compared to other types of flanges. If the temperature or type of product at the closures of the pipe fittings is a significant factor to consider, or when variable or cyclical forces may be applied, blind pipe flanges should be considered heavily.

Blind pipe flanges can be made from a variety of different materials, depending on the environmental conditions they will be exposed to. If they are going to be exposed to moderate temperatures, carbon steel should work. Extreme temperatures and pressures will require the use of alloy steels, while nickel, chromium, and molybdenum should be used if the product being transferred is corrosive. These materials are all far cries from the bamboo that was used to create the earliest hydrocarbon pipelines, recorded in ancient China in 500 B.C.

Why Do We Use Blind Pipe Flanges?

On a very general level, blind pipe flanges are most often used when the ends of pipes or pressure vessels need to be closed or sealed off. Usually, they are utilized in high pressure situations, to cut off the flow of liquids or gases. This is why they need to be able to withstand high stress situations, as the flange must not only withstand the pressure building up in the pipe itself, but stress caused by the traction of the bolts as well.

Usually, blind pipe flanges are used in the petrochemical industries, the pharmaceutical industry, the solar plant industry, and food and wastewater treatment plants. Therefore, the demand for blind pipe flanges will not be minimized in the near future.

There is much to consider regarding blind pipe flanges. It’s important that those ordering blind pipe flanges understand the materials their flanges are made from in particular. This will highly affect the performance of the flanges, as well as their longevity. Always work with a trusted distributor of goods like this to ensure you get the right materials for your next project. Lynco Flange & Fitting has been serving these industries since 1982, and we stand ready to provide expert assistance to your team.