What does the nominal diameter DN of a valve mean?
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This post was last edited by flute6 on 2010-9-24 08:51. What does the nominal diameter DN of a valve refer to, and what does it mean? Nominal pressure?
DN refers to the size of the flange.
DN refers to the diameter size; for example, DN50 means a diameter of 50
DN denotes the diameter of the valve; for example, DN80 indicates a valve with a diameter of 80 mm. The nominal pressure is the maximum operating pressure specified for the valve, denoted as PN. However, in China, there is confusion regarding the unit used to express PN – some use a value that is 10 times the actual pressure (in Mpa); for instance, PN16 means 1.6 Mpa. Others directly indicate the actual pressure in Mpa; for example, PN6.3 (Mpa) means an actual pressure of 6.3 Mpa. This lack of uniformity in units poses significant difficulties in making selection decisions. It is necessary to determine the correct unit based on the customer’s specific requirements or to ask the customer about it, in order to avoid errors
The nominal diameter refers to the inner diameter, but it is in imperial units, with a value that is slightly larger than millimeters
The nominal diameter is expressed in imperial units using inches, while in China it is expressed in mm; 1 inch is equal to 25.4 mm
This post was last edited by flute6 on 2010-10-3 02:42. It should be like this; this is a **standard title**. The above are my personal opinions
Agree with the 4th floor post; it was very detailed
The nominal diameter is only a nominal size; the actual inner diameter must be checked in relevant data.
The full name of DN, the nominal diameter, is also known as the outside diameter. It represents the standard diameter for various pipes and pipe fittings. It is not the actual outer or inner diameter of the pipe, although its value is often very close to or equal to the pipe’s inner diameter. In simple terms, it is just a set of standards for pipeline connections. The full name of PN, nominal pressure, refers to the pressure difference across the valve, rather than the maximum pressure that the valve can withstand. During operation, the valve is subjected to the pressures P1 and P2 of the media on its two ends, and the PN value represents ΔP. Its international unit is bar, with 1 bar = 0.1 MPA.
The nominal diameter is a value used in engineering, and it is the same as the nominal diameter of the pipe