Pipe Flanges are widely used as a popular category of pipe fittings. A flange is used to mechanically connect two pipes together. It can also be used to mechanically connect a pipe to a tee, valve, choke or any other piece of equipment. Flanges are available in round, square, and rectangular shapes. In some cases, flanges are usually in the shape of a ring or a plate to form a rim at the end of a pipe when fastened to the pipe. This is an example of closet flange.
A flange can also be a plate for covering or closing the end of a pipe. This is a blind flange. Thus, flanges are considered to be projecting or internal components which are used to support mechanical parts. They are like rims which are used to strengthen the mechanical part or they are a means of attaching that part to another part or surface.
Designs of flanges:
Various materials used in the making of flanges are as follows:
Pipe flange measurements:
- Stainless Steels
- Cast Iron
- Galvanized steel
- Carbon Steel
- PVC etc.
- Flange’s outside diameter (OD): which is measured
from outer edge to opposing outer edge.
- Thickness: which measures only the thickness of the
attaching outer rim, and does not include the part of the flange
that holds the pipe.
- Bolt circle diameter: which is measure from the center of
a bolt hole to the center of the opposing hole.
- Pipe size: Pipe flanges also have a corresponding pipe
size, generally according to accepted standards.
- Nominal bore size: All pipe flanges are sized according
to their nominal bore size. It is important when manufacturing and
ordering any type of pipe connector to match the bore size of the
piece with the bore size of the mating pipe.
To buy pipe flanges, the buyers should keep in
mind certain factors like:
- Type (Standard): Weld-neck, Blind, Slip-on,
- Standard facings: Ring-type joint, Raised face, Flat
face, Male/female, Tongue/groove
- Material: Selection of materials for pipe flanges
depends on the piping material and the nature of the
application. Material selection depends on certain factors like:
- Atmospheric corrosion
- Strength and
- Other features
- Should be light in weight
- Should be quick to assemble
- Can hold high pressures
- Can be repeatedly disassembled and resealed
- Heavy wall thickness
A wide variety of flange designs are available. They are available in
various shapes and sizes. Some of the popular designs are as follows:
- Butt weld
- Socket weld
- Rectangle etc.
Custom shapes and sizes are also manufactured by numerous
manufacturers. Various pipe flanges include machining details such as
gasket surfaces, facing details, non-standard drilling, bevel and radius
edges, o-ring grooves and raised or recessed faces. Some typical designs
on flanges faces are shown below.
How is a flange attached to a pipe?
The flange is attached to the pipe by:
Uses of pipe flanges:
- Welding: Welding is a process of fabrication that joins
materials, usually made of metals or thermoplastics, by causing
- Brazing: Brazing is a process of joining similar or
dissimilar metals whereby a non-ferrous filler metal or alloy is
heated to melting temperature (above 450°C; 800°F).
- Screwed fittings: Screwed fittings are like bolts and
nuts which are used almost exclusively in smaller pipe sizes and at
Flanges are used for variety of purposes. The main purpose is to
connect pipes but they are also used for connecting other equipments.
Flanges are fit to a variety of other components besides pipes. They are
fitted to bellows, ducts, wheels, and cameras. We give below the various
uses of pipe flanges:
- Flanges are also placed on beams to provide additional strength.
- They prevent the beam from failing.
- They are used for guide, as the flange of a train wheel.
- Flanges are used for attachment to another object like for
example, the flange on the end of a pipe, steam cylinder, etc.
- They are fixed on the lens mount of a camera.
- A flanged rail is a type of rail with a flange on one side to
keep wheels from running off.
Applications of pipe flanges:
Pipe flanges are widely used in pipe fittings of various industrial,
commercial and residential applications. Pipe flanges can be customized
to suit your application with various machining details. These pipe
flanges have been used extensively in:
Types of pipe flanges:
- UHV applications
- Hydraulic control systems for turbine generators
- High pressure ground support missile systems
- Nuclear and conventional power plant applications etc.
There are basically eight types of pipe flanges. Let us get to know
more about these flanges:
The points mentioned below will be a guide for the buyers: