In piping systems, PN (Pressure Nominal) indicates a component's pressure rating (in bars), showing its safe working pressure, while DN (Diameter Nominal) specifies the standard metric size (in millimeters) for pipe fittings, valves, and flanges, acting as a reference for connection compatibility, not exact dimensions. For example, a "DN50 PN16" valve fits a 50mm pipe and is rated for up to 16 bar.
Nominal diameter (DN) and nominal pressure (PN)
PN is an abbreviation for “Nominal Pressure,” which is a standardized unit of measurement used to express the maximum working pressure a valve can withstand without compromising its structure or functionality. In other words, PN is a measure of the valve's internal pressure resistance.
DN stands for 'Diameter Nominal'. Put simply, it is a rough translation of mm from imperial sizes, assuming that an inch is 25mm. We refer to a 12″ flange as DN300, when in fact it is 304mm. Please use the table below for your reference and if you have any other questions, please ask the Just Valves team.
A part number (often abbreviated PN, P/N, part no., or part #) is an identifier of a particular part design or material used in a particular industry. Its purpose is to simplify reference that item. A part number unambiguously identifies a part design within a single corporation, sometimes across several corporations.
RNs are trained to handle more complex medical situations and often work in fast-paced environments like hospitals, emergency rooms, and specialized clinics. PNs provide essential bedside care, monitor patient conditions, assist with daily activities, and report changes to supervising staff.
What Do DN and NPS Stand For? DN stands for diametre nominal, which denotes the size of a pipe (specifically, its inside diameter) in millimeters (mm). NPS, or nominal pipe size, is merely the non-metric equivalent in which the diameter is measured in inches (in.).
PN Is the nominal working pressure rating. The number used to describe PN is 10 times the value of the maximum allowable operating pressure (MAOP) at 20°C (MPa x10) based on a design factor of 1.25.
PN stands for "Pressure Nominal," which is a term used to describe the pressure rating of an HDPE pipe. It is a measure of the maximum pressure that an HDPE pipe can withstand at a specific temperature.
PN stands for "Pressure Nominal," and it is a designation used to denote the pressure rating of a material. It does not directly correlate to pressure in bars but is a standardized way to classify materials based on their pressure-handling capacity.
PN10: Designed for a maximum pressure of 10 bars (approximately 145 psi). Suitable for lower pressure applications like water lines, compressed air systems, and low-pressure heating systems.
The acronym PN stands for Pressure Nominal. When a pipe has a rating of PN16, it is designed to handle 16 Bar internal pressure. Poly pipe comes in a range of pressure ratings: PN10 which has a maximum pressure rating of 1000kpa. PN12.5 which is for a maximum of 1250kpa.
MEANING OF DN 400 IS Nominal Diameter 400mm/16"
The markings PN 40 and DIN 80 on the valve refer to its pressure rating and size specification, respectively. PN 40 means the valve can handle a maximum pressure of 40 bar (approximately 580 psi) at a reference temperature (typically 20°C). DIN refers to the standards set by the German Institute for Standardization.
It is common to identify pipes by inches using NPS or “Nominal Pipe Size“. NPS is often incorrectly called National Pipe Size, due to confusion with national pipe thread (NPT). The metric equivalent is called DN or “diametre nominel“.
In other words, for every NPS number there is a DN number; for example NPS 3/4" is equivalent to DN20. This means that a pipe having NPS 3/4" can also be defined as DN20, where 3/4 (0.75 inches) approximates the nearest standard size in millimeters which is DN20 since there is no DN19.
In the context of DN and PN of flanges, “DN” is an abbreviation for “Diameter Nominal” and refers to the size of the flange. The “PN” stands for “Pressure Nominal” and refers to the pressure grading of the flange.
PN (Pressure Nominal) is indicated in bar; for example, PN25 is 25 bar. 1 bar equals 14.5 psi. Sometimes manufacturers will include the psi rating as well. Flanged or lug-style valves are categorized by ANSI flange classes covered under ASME B16 standards.
PN 25 is a high-pressure rating used for high-pressure applications, including: 1. Power Generation: PN 25 pipes are used in power generation plants, as they can withstand pressures up to 25 bar.
The calculation formula of PN value is: PN = 2 × MRS / (C × (SDR-1)), where SDR (Standard Dimension Ratio) is the ratio of the outer diameter of the pipe to the wall thickness. From this formula, it can be seen that the PN value is proportional to the material strength and inversely proportional to the SDR value.
Understanding PPR Pipes PN 20 Meaning
The PPR pipes PN 20 meaning is simply that the pipe can safely handle up to 20 bar (2.0 MPa) of internal pressure at 20°C.
Definition of nominal diameter (DN)?
Defining this term in the simplest terms, we can say that the nominal diameter DN roughly defines the diameter inside the pipe given in millimetres. It is therefore given in the metric system, rather than in the commonly used imperial system.
DN is defined by the European standard ISO 6708 and is based on millimeters. It represents the approximate internal diameter of a pipe.
DN50 is a common standard specification, which represents the inner diameter of the steel pipe. DN is the abbreviation of Deutsches Institut für Normung (German Standardization Institute), which means "German Standard". 50 means that the inner diameter of the steel pipe is 50 mm.