What is a forged pipe fitting? Where is it used?
Forged pipe fittings have high quality and exceptionally high strength that can withstand high-pressure flowing gases and liquids. It has a thicker wall compared to several other types of fittings. The ASME B16.11 contains pressure and temperature ratings along with dimensions, markings, ratings, tolerances, and requirements of materials for forged fittings.
Forged pipe fittings are used in power generation, oil and gas, and chemical industries where fittings that can withstand extremely high pressure and can withstand corrosive media are a requisite.
How are forged pipe fittings manufactured?
The collar portion of the fitting is engraved with the required identification. This is a permanent mark engraved on all fittings. This helps the user of the fitting to identify the specifications and features of a particular fitting.
The marking includes:
- Trademark of manufacturer
- Country of origin
- Specification standard
- Size
- Working pressure
- Class pressure
- Material identification
- Heat number
Class pressures 3000 and 6000 are often labeled as 3M and 6M. M indicates 1000. 3M or 3000 indicates that a forged fitting can take on or withstand 3000 Psi.
What do the symbols of the forged pipe fittings such as 3M and 6M indicate?
Forged pipe fittings are designed in a variety of classes such as 2000, 3000, 6000, and 9000. The most commonly used ones are 3000 and 6000. Often it is seen that 3000 is denoted by 3M and 6000 as 6M. Here, the suffix M stands for or signifies 1000. It indicates the amount of gas and fluid pressure the fitting can withstand. For example, 6000M can take on 6000 Psi worth of pressure.
Major differences between 3000 and 6000:
3000 or 3M:
- Has a smaller body size.
- Thinner wall
- Light in weight
- Lower working pressure.
6000 or 6M:
- Larger body size
- Thick wall
- Heavy body weight
- Higher working pressure
What are the various types of forged pipe fittings available?
The types of forged fittings used commonly and that are widely available are 90D elbow, 45D elbow, straight coupling, 3-piece union, 3-way tee, end cap, end plug, hex nipple, etc.