1, what is the nominal pressure PN (MPa)?
The reference value related to the pressure resistance of piping system components is the design pressure that gives mechanical strength to piping components. Nominal pressure is generally expressed in PN.
(1) Nominal pressure ---- product compressive strength at the reference temperature, expressed in PN, unit: MPa.
(2) Reference temperature: different materials have different reference temperatures. For example, the reference temperature of steel is 250 ℃
(3) Nominal pressure 1.0Mpa, recorded as: PN 1.0 Mpa
2. What is the working pressure?
It refers to the maximum pressure specified for the safe operation of piping systems at all levels of piping maximum operating temperature. Working pressure is generally expressed in Pt.
3. What is the design pressure?
Is the maximum instantaneous pressure of the water piping system acting on the inner wall of the pipe. Generally use the working pressure and residual water hammer pressure and the sum. Design pressure is generally expressed in Pe.
4. What is the test pressure?
Used for compressive strength and air tightness testing of piping, vessels or equipment to achieve the pressure. Test pressure is generally expressed in Ps.
5. Nominal pressure, working pressure, the relationship between the design pressure
Nominal pressure is for the design, manufacture and ease of use and artificially specified nominal pressure. The unit of nominal pressure is actually pressure, commonly known as pressure in Chinese. Unit is "Pa" rather than "N".
Nominal pressure in English is nominal pres-surenomina: l in name or form but not in practice (nominal, nominal). The nominal pressure of a pressure vessel is the nominal pressure of the pressure vessel flange. The nominal pressure of pressure vessel flanges is generally categorized into 7 levels, i.e., 0.25, 0.60, 1.00, 1.60, 2.50, 4.00, and 6.40 MPa.
Design pressure = 1.5 x working pressure.
The working pressure is calculated by hydraulic calculation of pipe network.
1MPa = 10bar (bar) = 10.2kg/cm2 = 100N/cm2
Test pressure＞nominal pressure＞design pressure＞working pressure
Design pressure = 1.5 x working pressure (usual)
