What should be considered when passivating steam pipes?
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Hello everyone, the steam pipeline system for the project I am currently working on is about to undergo pressure testing, purging, and acid cleaning and passivation. The system is mainly divided into two pressure grades: S8 and S4. The S8 pipes are made of 20# carbon steel, while the S4 pipes are made of S304 stainless steel. For the pressure testing, it is planned to test and purge different types of pipelines separately; after purging, acid washing and passivation will be carried out. I have a few questions for everyone. 1. Is it necessary to purge steam pipes before acid cleaning and passivation? For purging, we plan to use compressed air or nitrogen, as steam may not be suitable. Is it better to use that kind of purge? 2. When pickling and passivating pipes, in addition to removing the bypasses from the steam flow meters and pressure reducers, should the bypasses of the drain valves also be removed? 3. Is it necessary to acid wash and passivate steam stainless steel pipes? Is there any difference from the pickling and passivation of carbon steel pipes?
Dismantle what needs to be dismantled, and connect the sections that need to be joined together~~~ Be careful when carrying out pickling; it’s best to hire a professional team for this task
It is safer and more reliable to find a professional construction team.
What is the diameter of the pipeline? Is it necessary to carry out acid cleaning and passivation? As many components as possible should be removed before purging; carbon steel and stainless steel are definitely different, and information on this can be found online
The pipes are not large; the largest size is DN150, and citric acid is used for pickling.