A few questions about non-metallic pipes?
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1. Can PP pipes or FRPP pipes be used with a pressure of 16 kilograms? 2. Which standard should be used for selecting pp pipe fittings: HG 20539-1992 or GB/T 18742-2017? 3. For exhaust pipelines in hydrogen fluoride and hydrochloric acid media, standard specifications for outer diameter and wall thickness are not provided in HG 20539-1992 for diameters larger than DN500; nor are there any standards for the outer diameter and wall thickness of pipes with PN16 rating. In GB/T 18742-2017, specifications apply only to pipes with diameters greater than DN200, and no details are given for PN16 pipes – is this meant to indicate that these standards do not apply? 4. The size and thickness table in the GB/T 4219-2008 standard for PVC pipe fittings does not provide specifications for the outer diameter and wall thickness of fittings larger than DN400; is there any applicable standard? I’m a beginner in the chemical industry; I hope experts can give me some guidance.
1. The pressure that PP pipes or FRPP pipes can withstand depends on factors such as their diameter, wall thickness, and material; generally, they can handle up to 16 kilograms of pressure. However, the specific applicability still needs to be determined based on the specific parameters of the pipeline. 2. For the selection of pp pipe fittings, it is recommended to use the latest version of the GB/T 18742-2017 standard, which is more comprehensive, standardized, and detailed compared to HG 20539-1992. 3. For exhaust pipelines in hydrogen fluoride and hydrochloric acid media, it is recommended to select appropriate **standards for design and selection. If the relevant standards do not specify the parameters for the pipeline you need, you can seek advice from professional technicians. 4. For the selection of PVC pipe fittings, it is recommended to refer to the GB/T 4219-2017 standard. If the standard does not contain the parameters for the required piping fittings, it is also possible to consult professional technicians to find a suitable standard. -
Thank you for your reply. Regarding the selection of PP pipe fittings for the second point, the GB/T 18742-2017 standard you recommended is only applicable to cold and hot water piping systems in buildings. I did not explain my question clearly enough; it concerns PP pipes used in the chemical industry. I was wondering whether GB/T 18742-2017 is also applicable in such cases.
I’m very sorry; I misunderstood. For the selection of PP pipe fittings used in the chemical industry, you can refer to the HG 20539 standard for plastic pipe fittings in the chemical industry. This standard sets out detailed requirements regarding the material, structure, dimensions, and connection methods of pp pipe fittings, and is suitable for use in the chemical industry. In the actual selection process, it is recommended to conduct an evaluation and make a decision based on specific circumstances. Thank you again for your corrections and reminders. -
There is still a difference between the pressure theoretically achieved and the pressure actually used; you also need to take into account the safety factor. It’s like a rubber band stretched to its limit; it may not break right away, but who knows how long it can hold.
Design pressure: In actual production, the pressure is relatively low, at around 3 kilograms only at the outlet of the magnetic pump.
QB/T 5099-2017 \"Industrial β-crystalline homopolypropylene (β-PPH) piping systems\", dn≤800, PN≤1.6.
Thank you for sharing. QB/T 5099-2017 provides specifications only for fittings of DA500 and above with PN10 or lower; it does not cover fittings with DN500 or above and PN10 or higher.
With such large pipes and high pressures, using non-metallic pipes is no longer suitable; it is recommended to switch to steel-lined pipes.