Confused about PN and MPa pressure ratings? This guide breaks down their differences (PN=nominal pressure, MPa=megapascals), explains where each is used (e.g., pipes vs. industrial systems), and helps you avoid selection mistakes. Read now to master pressure standards! Read now"
Two pressure terms: What is the difference between PN and MPa?
In daily work, PN and MPa are often used to express pressure, but what is the difference between the two and what is the relationship between them? I wonder if you all understand? Before writing this article, I was very confused. Now I will share what I have sorted out with you.
1. The difference between PN and MPa
● Different definitions:
—— PN: PN is the abbreviation of "Nominal Pressure", which means nominal pressure. It is a standardized nominal value. It is not the actual measured pressure, but a reference value for easy classification and identification. Note: PN is defined based on the pressure resistance of standard temperature (generally 20°C) and standard materials (such as steel). In design and use, PN not only reflects the pressure resistance, but also comprehensively considers the material strength and temperature effects.
—— MPa: MPa is the abbreviation of "Megapascal", which means the pressure unit "Megapascal" (1 MPa = 10⁶ Pa). It is an actual pressure value that describes the real force applied per unit area.
● Different uses:
—— PN: Mainly used for pressure grading and matching of pipes and accessories (such as flanges and valves), mostly used in Europe and Asia (American standards are represented by Class). The unit of PN is bar, 1 bar = 0.1 MPa. For example: PN10 means the nominal pressure is 10 bar, that is, 1.0 MPa.
—— MPa: Commonly used to measure actual working pressure, such as: fluid pressure in a pipeline, pressure output by a pump or pressure equipment. MPa is an internationally used engineering unit that directly represents a physical quantity and is related to the actual operating status of the equipment.
For easy understanding, let's make a table for comparison:
Item PN
(Nominal pressure) MPa (Megapascal) Essence Nominal value (for classification and grading) Actual pressure value (describes the operating status) Unit bar (1bar=0.1MPa) MPa (International System of Units) Purpose Used to identify the pressure level of pipes and accessories Description The actual pressure or working pressure of the fluid Relationship with temperature is related to the material temperature Not directly dependent on temperature, the actual measurement value range and change Fixed level (such as PN6, PN10, etc.) can change continuously
2. The relationship between PN and MPa
In practical applications, PN and MPa are interrelated:
● Selection of pipes and accessories When the actual pressure (MPa) of the fluid is known, select the appropriate PN level to ensure safety. For example: the working pressure of a pipeline is 0.8 MPa, select PN10 (1 MPa) pipe accessories.
● The impact of temperature on PN PN is usually the nominal value at 20°C. When the temperature rises, the strength of the material will decrease, and the corresponding actual pressure resistance value may be lower than the PN value. For example: the actual pressure resistance value of a PN40 flange at 200°C may be only about 2.5 MPa (need to check the standard table).
● Safety factor When selecting pipelines and equipment, a certain safety margin is usually left for the PN value. For example: if the actual working pressure is 1.2 MPa, PN16 accessories can be selected.
You should be able to understand it. Simply put, PN is a concept defined by humans to facilitate the classification of pipelines and fittings. The unit is bar, which is mostly used in the standard system of Asia and Europe; and MPa is a unit that describes the actual pressure size.
If there is anything wrong, please discuss it.
One-stop supply of various ISO ASTM PVC/PPR/HDPE water supply Drain Rain pipe and fittings: flange/valve/elbow/tee/reducer Drinking water, agriculture, industry, chemical industry
Whatsapp:+86 18388080854 Mail:kevinchen940205@gmail.com
#pvcpipe #hdpepipe #pprpipe #pvcpipefittings #hdpepipefittings #pprpipefittings #zhongcaipipe #HDPEDripTape #Agriculture #WaterEfficiency #CustomSolutions #SoutheastAsia #Farmers #LimitedTimeOffer
Contact Us:
Whatsapp/wechat:+86 18388080854
Email:kevinchen940205@gmail.com
Web:hengcaipipe.com