Regarding the classification of pressure pipelines
Thread Content
A 50% ethylene glycol aqueous solution used as a hot and cold medium, with a pressure greater than 0.1 MPa and a pipe diameter larger than DN50 – does this constitute a pressure pipeline?
It belongs to. Ethylene glycol is a flammable liquid. Announcement by the General Administration of Quality Supervision, Inspection and Quarantine on the Revision of the “Catalogue of Special Equipment” (No. 114, 2014). Pressure pipelines refer to tubular devices that use pressure to transport gases or liquids; they are defined as those with a maximum working pressure of 0.1 MPa or more (gauge pressure), where the medium is a gas, liquefied gas, steam, or a flammable, explosive, toxic, corrosive liquid with a maximum working temperature equal to or higher than its standard boiling point, and whose 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. Notice from the General Office of the Quality Inspection Administration on Issues Related to the Safety Supervision of Pressure Pipelines and Cylinders (Quality Inspection Office Special [2015] No. 675) “I. Issues Related to the Safety Supervision of Pressure Pipelines (1) Regarding the range of media used in pressure pipelines as specified in the new ‘Catalog’. The toxic, non-flammable, and non-corrosive gases referred to in the definition of pressure pipes in the new Catalogue – namely, pipes with a nominal diameter of less than 150 mm and a maximum operating pressure of less than 1.6 MPa (gauge pressure) that transport such gases – do not include liquefied gases, steam, and oxygen. ”
In the explanations on the 4th floor, if the conditions are met, it is considered a pressure pipeline. The several conditions mentioned by the original poster are definitely within the scope of pressure pipelines.
Do you also determine whether it belongs to the category of pressurized pipeline media from a toxicity perspective?
Condition 1: The maximum operating pressure is greater than or equal to 0.1 MPa (gauge pressure), and the medium is a gas, liquefied gas, steam, or a liquid that is flammable, explosive, toxic, corrosive, with a maximum operating temperature greater than or equal to its standard boiling point. Condition 2: The nominal diameter of the pipeline is greater than or equal to 50 mm. The working environment of the medium in question clearly meets these two conditions, so it constitutes a pressure pipeline.
I was wondering if the original poster has reached a conclusion regarding this last question. Our company is also conducting inspections of pressure pipelines, and I think that ethylene glycol solution is a toxic substance, so it should be classified as a pressure pipeline.