Flanges are projecting or internal components used to support mechanical parts. Let’s see here about different types of flanges.
The second mostly used joining method after welding is flange. Flanges are used when joints need dismantling. It provides flexibility for maintenance and connects the pipe with various equipment and valves. Breakup flanges are added in the pipeline system if regular maintenance is required during plant operation. A flanged joint is composed of three separate and independent but interrelated components; the flanges, the gaskets and the bolding and all these are assembled by the fitter. Special controls are required in the selection and application of all these elements to attain a joint which has acceptable leak tightness. However, it is not advisable to use flanges in underground piping where it requires to be buried. The flange is also a most common source of leak and fire in a process plant. There are varieties of flanges available through the flange supplier India to suit the requirements of the customers and they are as follows:
Threaded Flanges:
These are otherwise known as screwed flange. These are having thread inside the flange bore which fits on the pipe with matching male thread on the pipe. This type of joint connection is speedy and simple but not suitable for high pressure and temperature applications. These flanges are mostly used in utility services such as air and water.
Socket Weld Flanges: These flanges have a female socket in which pipe is fitted. Fillet welding is done from outside on the pipe. Generally, these are used in small bore piping and only suitable for low pressure and temperature applications.
Slip-On Flanges:
Slip-on Flange has a hole with matching outside diameter of pipe from which pipe can pass. The flange is placed on pipe and fillet welded from both inside and outside. Slip-On flange is suitable for low pressure and temperature application. This type of flange is available in large size also to connect big bore piping with storage tank nozzles. Normally, these are of forged construction and are provided with the hub. Sometimes these are fabricated from plates and are not provided with the hub.
Lap Joint Flanges:
These come with two components – a stub end and a loose backing flange. Stub end is butt welded to the pipe whereas backing flange freely move over the pipe. The backing flange can be of different material than stub material normally of the carbon steel to save the cost. Lap flange is used where frequent dismantling is required and space is constrained.
Weld Neck Flanges:
These are the most widely used flanges in process piping. These give the highest level of joint integrity due to butt welded with a pipe. These are used in high pressure and temperature application. These are bulky and costly when compared to other types of flanges.
Blind Flanges:
This is a blank disc with bolt hole. These types of flanges are used with another type of flange to isolate the piping system or to terminate the piping as an end. These are used as a manhole cover in the vessel.
All the forging products manufacturers will produce various types of carbon steel, alloy steel, stainless steel and duplex steel flanges as per customer specific requirements/drawings.
