What is “inch”: Inch (“) is a common specification unit for the American system, such as steel pipes, valves, flanges, elbows, pumps, tees, etc., such as the specification is 10″.
Inches (inch, abbreviated as in.) means thumb in Dutch, and one inch is the length of a thumb. Of course, the length of the human thumb is also different. In the 14th century, King Edward II issued the “standard legal inch”.
It is stipulated that the length of the three largest grains selected from the middle of the barley ear and arranged in a row is one inch.
Generally 1″=2.54cm=25.4mm
What is DN: DN is a commonly used specification unit in Chinese and European systems. It is also a specification for identifying pipes, valves, flanges, pipe fittings and pumps, such as DN250.
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, called the average inner diameter.
What is Φ: Φ is a general unit, which refers to the outer diameter of pipes, elbows, round steel and other materials. It can also be said to be diameter. For example, Φ609.6mm refers to the outer diameter of 609.6mm.
Now that we have figured out what these three units represent, what is the connection between them?
First of all, “The meaning of “DN” is almost the same as that of DN, basically it means the nominal diameter, indicating the size of this specification, and Φ is to combine the two.
For example: if a steel pipe is DN600, and the same steel pipe is marked with inches, it becomes 24″. Is there any connection between the two?
The answer is yes! The general inch is the direct multiplication of the integer by 25, which is equal to DN, such as 1″*25=DN25 2″*25=50 4″*25=DN100 and so on.
Of course, there are also different ones, such as 3″*25=75, rounded to the nearest DN80, and some inches with semicolons or decimal points, such as 1/2″ 3/4″ 1-1/4″ 1-1/2″ 2-1 /2″ 3-1/2″, etc., these cannot be calculated like that, but the calculation is roughly the same, basically the specified value:
1/2″=DN15 3/4″=DN20 1-1/4″=DN32 1-1/2″=DN40 2-1/2″=DN65 3-1/2″=DN90
Post time: Mar-10-2022
