The meaning of diameter Φ, diameter DN, inch these specification units

What is an inch ": Inch (") is a common specification unit of the American system, such as steel pipes, valves, flanges, elbows, pumps, tees, etc. If the specification is 10 ".

What is DN: DN is a standard unit commonly used in Chinese and European systems. It is also the specification for marking pipes, valves, flanges, fittings, and pumps, such as DN25.

DN refers to the nominal diameter of the pipe (also known as the nominal diameter). Note: This is neither the outer diameter nor the inner diameter. It is the average of the outer diameter and the inner diameter, which is called the average inner diameter.

What is Φ: Φ is a universal unit, which refers to the outer diameter of pipes and / or elbows, round steel and other materials. It can also be said to be the diameter, such as Φ609.6mm refers to the outer diameter of 609.6mm.

"Inch" has the same meaning as the DN label, basically it means the nominal diameter, indicating the size of this specification, Φ is a combination of the two.

The general inch is an integer directly multiplied by 25 to equal DN, such as 1 "* 25 = DN25 2" * 25 = 50 4 "* 25 = DN100, etc.

1/2 "= DN15 3/4" = DN20 1-1 / 4 "= DN32 1-1 / 2" = DN40