Flanges have been an integral part of the piping system. There are varieties of flanges that are in use in different industries. Every industry demands a unique set of flanges according to their requirements. Through this article, you will be familiar with the different range of flanges available; their sizes, shapes, advantages, demerits and use. Scroll down to know your flanges better. What is a flange? A flange is a metal disc used to join pipes or valves or tubes to form a piping network, thereby providing support and strength and prevent leakage. It becomes easy to access or clean or inspect a pipeline system as flanges are commonly welded or screwed into pipes or valves and joined with bolts.Flanges differ because of different metals used – Stainless Steel, Cast Iron, Ductile Iron, Carbon Steel, etc. thereby varying in ‘pressure classes’. Every flange is classified under a pressure class, depending on its capacity to withstand a particular amount of temperature. Also, the metal used determines how much force or heat a flange can face. If the temperature increases, the pressure rating of the flange decreases and vice versa. Browse this site listing about exhaust flanges
Now let’s take a look at the types of the flange.
Types of Flanges:
As noted earlier, different industries demand various kinds of flanges according to their usage and pressure classes. The most commonly used flanges are weld-neck, slip-on, socket, lap-joint, threaded and blind flanges.
- Weld-neck flanges:
Welded to the base of the pipe, the bore of the flange matches the bore of the pipe, thus allowing uninterrupted product flow and reduces turbulence and erosion at the joints too. High-pressure applications use them, with their ability to provide supporting strength along with stress distribution. Though these flanges can be radiographed for flaw detection and are highly durable, they are quite expensive.
- Slip-On Flanges:
They have bores with a diameter slightly larger than the pipe; this helps it to slideslip over the pipe. This flange is then welded inside and outside too, with fillet welding. They are thinner, cost-effective and are easy to use in fabricated applications.
- Socket weld flanges:
These flanges are counter-bored i.e. the bore of the flange and pipe, both are same, thereby providing a good flow of the product through the tube. Initially used for small-sized high-pressure pipes, they are now employed in powerful systems too. A demerit of socket weld flange is the gap created between the pipe and flange during the welding process, which may lead to corrosion of the metal.
- Lap joint flange:
Commonly provided with a stub end, Lap joint flanges swing over the pipe, reducing the need for welding. They are re-usable and inexpensive as they do not come in contact with the inner fluid. Besides, they can be easily assembled and dismantled for quick inspection.
- Threaded flanges:
Their bore contains threads which are easy to install to pipes that have external threads. They are low priced and fit best for small pipes and in low-pressure applications. They are very beneficial in highly combustible industries where welding is dangerous.
- Blind flanges:
They are mostly used to seal the end or opening of a pipe, which is why they come without a bore. Allowing quick access to the pipe these flanges come in handy for inspection and pressure tests.