Flange – Blind Flange

What is blind flange?

A blind flange is a connecting device for two large diameter pipes, usually two flange plates and a number of fastening bolts. Moreover, It without a hole in the middle, which is usually used for blocking the pipe opening and is a detachable sealing device.

There are many types of blind sealing surface for it, including flat surface, convex surface, concave and convex surface, tenon and groove surface, ring connecting surface.

product categories

Our company mainly supplies the following two blind flanges, the main materials are carbon steel, stainless steel, alloy steel.

plate blind flange

 It is a solid circle with a handle and is used in systems that are normally isolated.

Spectacle Blind Flange

It is shaped like a figure 8, one end is a blind flange, and the other end is a throttling ring, but the diameter is the same as the diameter of the pipe, which does not have throttling effect.

In short, it is easy to use. Use blind flange ends when isolation is required. When normal operation is required, use the throttle ring end. It can also be used to fill the installation gap of the blind flanges on the pipeline. Another feature of it is the obvious identification, easy to identify the installation status.

function:

The blind flanges play the role of isolation and cutting, which hasand the same function as the head, pipe cap and welding plug. Due to its good sealing performance, it is generally used as a reliable means of isolation for systems that require complete isolation.

Matters needing attention

• Firstly, under the premise of meeting the process requirements, as few blind flanges as possible.
• Secondly, the blind flanges must be indicated as normal opening or normal closing.
• Thirdly, the part of the blind flanges set in the cutting valve, upstream or downstream, should be determined according to the cutting effect, safety and process requirements.

Industry standard:

• Ministry of Chemical Industry standards: HG20592-2009、HG20615-2009、HG20601-97.
• Mechanical Department standard：JB/T86.1-94、JB/T86.2-94.
• Power line standard: D-GD86-0513.

National standard:

• Steel pipe flange cover: GB/T 9123-2010.
• Marine blind steel flange: GB/T4450-1995.

Pressure range:

•  European Monetary System: PN2.5Bar、PN6Bar、PN10Bar、PN16Bar、PN25Bar、PN40Bar、PN63Bar、PN100Bar、PN160Bar、PN250Bar、PN320Bar、PN400Bar.
• The American System: 150LB(PN20Bar)、300LB(PN50Bar)、600LB(PN110Bar)、900LB(PN150Bar)、1500LB(PN260Bar)、2500LB(PN420Bar).