Is this pipeline a pressure pipeline?

The Regulations on the Safety Supervision of Special Equipment define pressure pipelines as tubular devices that use a certain pressure to transport gases or liquids. Such pipelines are those with a maximum operating pressure of 0.1 MPa (gauge pressure) or more, handling gases, liquefied gases, steam, or liquid media that are flammable, explosive, toxic, corrosive, and have a maximum operating temperature equal to or higher than their standard boiling point; furthermore, their nominal diameter must be greater than 25 mm. Classification of pressure pipelines: Pipelines can generally be classified based on their main material, installation method, properties of the medium transported, and other characteristics related to their use. Pressure pipelines are classified into industrial pipelines, utility pipelines, and long-distance pipelines according to their uses. Industrial pipelines refer to the pipes used for transporting process media, utility pipes, and other auxiliary pipes that belong to enterprises and institutions. This includes process pipelines that extend beyond the factory boundaries but are under the jurisdiction of enterprises or institutions. Public pipelines refer to gas pipelines and heat pipelines used for public services or domestic purposes within a city or town. Long-distance pipelines refer to pipelines used to transport commodity media between production sites, storage facilities, and users.

It does not fall under the category of pressure pipes; it is a flammable liquid, and it should be classified according to the following criteria: 1. Pressure greater than 0.1 MPa, 2. Nominal diameter greater than 25 mm, 3. Maximum operating temperature equal to or higher than the liquid’s standard boiling point. The first two conditions are met, but the third one is not (operating temperature: 35 degrees)

According to the classification rules set out in the \"Rules for Permitting the Design of Pressure Vessels and Pressure Pipelines\" TSG R1001-2008 issued by the General Administration of Quality Supervision, Inspection and Quarantine, the situation described by the poster falls under the category of pressure pipelines. Industrial pipelines that meet one of the following conditions are classified as GC1 grade: (1) Pipelines that transport media with an extreme hazard level as specified in GB5044‑85 \"Classification of Hazards from Occupational Exposure to Toxic Substances\", highly hazardous gaseous media, and highly hazardous liquid media whose operating temperature is above their standard boiling point ； ⑵Pipelines that transport flammable gases of Class A or B, or flammable liquids of Class A (including liquefied hydrocarbons), as specified in the Fire Protection Design Code for Petrochemical Enterprises GB50160－1999 and the Fire Protection Design Code for Buildings GB50016－2006, and whose design pressure is 4.0 MPa or higher ； ⑶Pipelines that transport liquid media and have a design pressure of 10.0 MPa or more, or a design pressure of 4.0 MPa or more together with a design temperature of 400°C or more. Industrial pipelines that meet one of the following conditions are classified as GC2 grade: pipelines other than GC3 grade, with a toxicity level of the medium, fire hazard (flammability), design pressure, and design temperature that are all lower than those specified for GC1 grade pipelines. Industrial pipelines that meet one of the following conditions are classified as GC3 grade: pipelines that transport non-toxic, non-flammable liquid media, with a design pressure of less than or equal to 1.0 MPa, and a design temperature greater than –20°C but less than 185°C. This post was last edited by mfjxg on 2009-2-2 09:29]

It belongs to pressure pipelines! :) This is a flammable liquid, and it should be handled in accordance with the rules for pressures greater than 0.1 MPa

My opinion: This is a pressure pipeline; please refer to the definition of pressure pipelines given on the second floor. According to the provisions of the \"Rules for Design Approval of Pressure Vessels and Pressure Pipelines\" TSG R1001-2008, it should be classified as GC2 category. The download address for the rule above is: http://bbs.hcbbs.com/viewthread. ... D%BF%C9%B9%E6%D4%F2 This post was last edited by WSL01218 on 2009-2-11 09:45]

I think there is a problem with this analysis. In the definition, \"liquid media that are flammable, explosive, toxic, corrosive, and have a maximum operating temperature equal to or higher than their standard boiling point,\" these various conditions should be considered as parallel to each other rather than in a hierarchical relationship. Therefore, based on what the original poster has provided, it should be considered a flammable liquid, and thus falls under the category of pressure pipelines. The specific classification, in accordance with the classification rules provided on the 4th floor, can be defined as GC2.

According to the classification rules set out in the \"Rules for Permitting the Design of Pressure Vessels and Pressure Pipelines\" TSG R1001-2008 issued by the General Administration of Quality Supervision, Inspection and Quarantine, the situation described by the poster falls under the category of pressure pipelines. By definition, what was said on the 2nd floor makes it clear that the following three conditions must be met simultaneously: (1) Pressure. The maximum operating pressure is greater than or equal to 0.1 MPa (gauge pressure). This pipe is 3 kilograms, which certainly meets the requirement. (2) Medium. Gases, liquefied gases, vapor media, or liquid media that are flammable, explosive, toxic, corrosive, and have a maximum operating temperature equal to or higher than their standard boiling point. Vinyl acetate is flammable and explosive; of course, this condition is also met. (3) Pipe diameter. Pipes with a nominal diameter greater than 25 mm. The pipeline is a DN50 pipeline. Therefore, this pipeline meets all three of the above conditions and is considered a pressure pipeline.

I would also like to share my opinion on whether this pipeline is a pressure pipeline. Over many years of working on the design of pressure pipelines, I have identified a pattern: when transporting a certain substance and determining whether the pipeline in question is a pressure pipeline, if two conditions are met (as mentioned above), then the other condition should be adjusted to a higher level; if it can be adjusted to such a level, the pipeline must be designed as a pressure pipeline. Of course, pipelines with a diameter of 25 DN or less do not qualify as pressure pipelines. This is because what we consider usually are foreseeable situations, whereas accidents often occur as unforeseen events. For example, as mentioned earlier, the boiling point of vinyl acetate is 73°C and the operating temperature is 35°C; however, a malfunction in the pump or exposure of the pipes to sunlight can cause the temperature to reach or exceed the boiling point, leading to an accident. Therefore, for safety reasons, this pipeline must be designed and installed as a pressure pipeline.

It certainly belongs to pressure pipelines, transporting media at a pressure of 0.3 MPa

It certainly falls under pressure pipelines, according to the definition of pressure pipelines