In industrial production, the use of chemical pumps is more common, in the installation of chemical pumps, pipeline valves are essential, for the identification of the valve DN, inches, φ what does it represent? In the design or procurement of pipelines, pipes, fittings, valves and pumps, we often encounter units such as DN, inch, φ, and so on. There are also a lot of users, who are not clear and can not be compared with the model. The following is to introduce some marks:
Diameter symbol is "φ", belongs to a Greek letter, pronunciation is "FAI", and it has a very close relationship with the first two, because it can replace the above two identification units, the use of THE PIPE or pipe identification is a clear one, without conversion direct, such as φ 219, φ 508, φ 1020 and so on, This identification method is also a more extensive one.
DN is mistaken for inner Diameter by many friends. Indeed, DN and inner Diameter are somewhat close, but only close, its real meaning is the Nominal Diameter of pipelines, pipelines and accessories. Nominal Diameter, also known as Mean Outside Diameter, is almost an average outer Diameter.
The value of DN is basically very common in China, but it can only represent a part of the pipeline, pipe and pipe valve fittings. Why is it a part of it? Because in the domestic pipeline system, there can be two kinds of outer diameter (φ is the outer diameter of the pipeline or pipe, we will explain in detail later), such as DN100, there are domestic I series and II series (also useful to mark A series and B series), DN100 I series and A series are φ 114.3, The DN100's SERIES II and B are φ 108. So behind the present plan and detail how much DN if no Φ indicate the pipe diameter, when you use the DN marked need is clear I series (A series) or series II (B) series, so in the process of purchasing and inquiry is very clear, no need for communication and confirm you know is what kind of outside diameter of pipe or fittings.
"Inch" is an English unit, more commonly used in America and Europe, and it is also a unit. Of course, it is divided into pipes and tubes. Today, we will elaborate on the pipes and fittings of the Pipe class.
In the Pipe Pipe, the inch does not distinguish the outside diameter of the two kinds of pipes like the DN unit. It belongs to a specific unit. For example, 4" clearly indicates that the outside diameter is 114.3, while 10" is φ 273.