Questions about the classification of pipeline materials in GB50316?
Thread Content
According to the classification of petroleum products in the GB50316 Code for Design of Industrial Metal Piping, Category A2 fluids refer to toxic fluids; exposure to such fluids can lead to poisoning to varying degrees, but recovery is possible once exposure is ceased. Toxins equivalent to Grade II and below (high, moderate, low hazard) as specified in GB 5044 \"Classification of Hazards from Occupational Exposure to Toxic Substances\". Class B fluids refer to those fluids that, under environmental or operational conditions, are gases or liquids that can vaporize to form gases; such fluids can be ignited and burn continuously in air. Question: Toluene is moderately toxic, can be ignited and burn continuously in air – is it a Class A2 or Class B fluid? Gasoline has low toxicity, can be ignited and burn continuously in air; is it a Class A2 or Class B fluid?
Pressure pipelines are subject to GBZ 230-2010, while pressure vessels are subject to HG/T20660-2017
Pressure vessels in accordance with HG/T20660-2000
Generally, the principle is to go with the higher value rather than the lower one. Class A is classified based on toxicity, while Class B is classified based on flammability. The design and manufacturing requirements are basically similar for Classes A2 and B.
The owner needs to understand that the fundamental purpose of such classification is to determine the grade of industrial pipelines. For substances like toluene, which are both toxic and flammable, they should be classified according to the category that results in a higher pipeline grade. Currently, the GBZ 230-2010 standard no longer lists the toxicity levels of common substances; the person in question needs to make judgments based on the specifications for the characteristics of the substance in question, in accordance with the standard.