Does the relevant department have the ultimate authority to define pressure pipelines? Those with very clear concepts, please join the discussion
Thread Content
Example 1: Recently, I had to prepare new drawings for the sulfuric acid pressure pipeline at the pump outlet, as the owner was informed by the relevant authorities that such drawings were needed. The problem is that the nitric acid pipeline nearby doesn’t seem to qualify as a pressure pipeline; according to the definitions, it should also be considered a pressure pipeline, so why isn’t it required to have drawings for it? Is it up to a certain department to decide whether something counts as a pressure pipeline? Example 2: Could an asphalt pipeline be a pressure pipeline? Since liquid asphalt is considered a flammable liquid, it falls under the category of pressure pipes according to the definition of such pipes. But the owner informed a certain department that asphalt could be omitted. Is it really possible to do this? Am I wrong? Summary: There are generally no disputes regarding the classification of pressure pipelines for gases, but there are significant controversies regarding those for liquids. According to Definition 1, liquids are classified as follows: 1 flammable, 2 explosive, 3 toxic, 4 corrosive, 5 with a maximum operating temperature equal to or higher than the standard boiling point. A liquid that meets any one of these 5 conditions is eligible to be used in pressure pipelines. But many of these conditions have been ignored. After all, there are few things that satisfy everyone; what’s done only ends up annoying the owners of the pressure pipelines. Please ask an expert to give a final decision
Sulfuric acid, nitric acid, and asphalt pipelines – all are included as long as the pressure and nominal diameter are specified; there is no doubt about this
But in reality, all these pipes aren’t taken into account; you still can’t do anything about it
Both our sulfuric acid and sodium hydroxide are transported through pressure pipelines; there is no asphalt involved, so it’s not clear.
This post was last edited by lzhrain on 2016-12-16 09:31. Well, it’s not exactly the case; owners should manage them as pressure pipelines (although in practice this isn’t done). The “Catalogue of Special Equipment” defines a pressure pipeline as a tubular device that uses certain pressure to transport gases or liquids. Such devices are considered to fall under this category when their maximum operating pressure is 0.1 MPa (gauge pressure) or more, when the medium is a gas, liquefied gas, steam, or a liquid that is flammable, explosive, toxic, corrosive, and whose maximum operating temperature is equal to or higher than its standard boiling point, and when the nominal diameter is 50 mm or more. Except for pipes with a nominal diameter of less than 150 mm and a maximum operating pressure of less than 1.6 MPa (gauge pressure), as well as the pipes that form part of the equipment used for transporting non-toxic, non-flammable, and non-corrosive gases. Among them, the safety supervision and management of oil and gas pipelines shall also be carried out in accordance with laws and regulations such as the Work Safety Law and the Oil and Gas Pipeline Protection Law.
Just focus on managing design-related matters; stay out of other things, as you can’t manage them anyway
If institutional norms aren’t implemented, as long as you can carry them out, it doesn’t matter what others do.