Seeking advice on determining PP pipe specifications
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I’m not good at working with pipes, so I’m seeking advice here. :) PP pipes are used for: 1. Connecting the outlet of the reaction tank to the inlet of the centrifugal pump, with a pipe size of DN50; 2. Connecting the outlet of the centrifugal pump to the inlet of the filter press, also with a pipe size of DN40. Temperature requirement: capable of withstanding 100 degrees (maximum operating temperature is 80 degrees). Pressure requirement: 0.6 MPa. Questions: 1. What diameters and wall thicknesses should be chosen for the PP pipes? Is it necessary to use FRPP pipes that are reinforced with glass fibers? 2. A question from someone who is not very familiar with this topic: Is the diameter of PP pipes specified using the DN nominal diameter or the outer diameter? For example, for a DN50 connection, what outer diameter should the pipe have?
The pressure is 0.6 MPa, which classifies it as a low-pressure pipeline; pipes with conventional thickness are sufficient. The diameter should be determined based on the nominal diameter of the pipeline connections. When purchasing PP pipes, you can specify that the selection should be based on the nominal diameter, or you can indicate that it should be based on the outer diameter. For a DN50 connection, a pipe with a DN50 diameter is appropriate; the usual outer diameter in this case is φ63, though this may vary depending on the wall thickness
It can withstand a pressure of 0.6 Mpa and temperatures ranging from 80 to 100 degrees. In theory, PP can be used for this purpose, but this already represents the upper limits for temperature and pressure tolerance of PP. If the material is highly acidic or alkaline and poses a significant risk to human health, it is recommended to use a steel-lined PTFE version; although it is slightly more expensive, it offers greater reliability.
PP pipes are specified by their outer diameter; this is stated in the **standards. Pipes with a diameter of 50 need to be connected using flanges, and I think the installation process isn’t any easier than that of steel pipes. Additionally, if you use PPR pipes, your material design does not comply with the **standards, as the temperature exceeds the allowed limits
Can PP material be used at 100 degrees? It’s easy to run into problems; there are lessons to be learned
Reply to Floor 1: It is not recommended to use PP pipes at temperatures between 80 and 100 degrees, as problems can easily occur during operation; for safety reasons, it is suggested that the poster choose steel-lined PTFE pipes. 5# qazxsw119
The Vicat softening temperature is 90 degrees for PPH and 65 degrees for PPR. In China, PPR pipes are more commonly used; at temperatures above 60 degrees, it’s not advisable to use PPH pipes – instead, PVDF pipes should be used, as they can withstand temperatures up to 120 degrees. 1. If possible, use FRP/PVDF pipes; pure plastic pipes have poor mechanical properties, require many supports, and are costly. For pure plastic pipes, an old SDR11 standard is sufficient. 2. DN50 is the nominal diameter; the outer diameter should be 63, DA63