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SMGI’s Flanges
A flange is a method of connecting pipes, valves, pumps and other equipment to form a piping system. It also provides easy access for cleaning, inspection or modification. Flanges are usually welded or screwed. Flanged joints are made by bolting together two flanges with a gasket between them to provide a seal.
SMGI’s Pipe flanges are protruding rims, edges, ribs, or collars used to make a connection between two pipes or between a pipe and any type of fitting or equipment component.

Flange Types
The most used flange types in Petro & chemical industry are as below.
All types except Lap Joint flange are provided with a raised face.
  • Welding Neck flange
  • Slip On flange
  • Socket Weld flange
  • Lap Joint flange
  • Theraded flange
  • Blind flange
Types of pipe flange include
Welding neck flanges - Butt welded onto the end of a pipe, providing a flange that is suitable for high temperature and pressure.

Threaded flanges - Have an internal (female) thread, a threaded pipe is screwed into it. This is relatively easy to fit but not suitable for high pressure and temperature.

Socket-welded flanges - Have a plain hole with a shoulder at the bottom. The pipe is inserted into the hole to butt against the shoulder and is then welded into place with a fillet weld around the outside. This is used for small diameter pipes operating at low pressure

Slip-on flanges - Have a plain hole but without the shoulder. Fillet welds are applied to the pipe on both sides of the flange.

Lap Joint flanges - Consist of two parts; a stubend and a backing flange. The subend is butt-welded to the end of the pipe and includes a small flange without any holes. The backing flange can slide over the stubend and provides holes to bolt to another flange. This arrangement allows disassembly in confined spaces.

Blind flanges - A form of blanking plate that is bolted to another pipe flange to isolate a section of piping or terminate piping.