Pipeline classification issue!
Thread Content
Steam is to be supplied from the boiler room within the factory complex to the heat exchange station in the residential area, using one steam pipeline with a diameter of DN400. The pipeline running from outside the factory to the heat exchange station in the area falls under the GB category; so what about the pipelines inside the factory complex? By GC or GB. If it is in accordance with GC within the factory perimeter, then this steam pipeline is divided into two sections at the boundary of the factory wall, with two sets of design standards and acceptance criteria. Is that so?
In accordance with China’s current safety technical specifications, steam pipelines within factory premises shall be designed and inspected in accordance with GB. This is because steam pipelines belong both to thermal systems and to special equipment; their design, fabrication, installation, and use must all comply with **relevant safety technical specifications. From an engineering practice perspective, GB is more suitable for the properties of steam pipes. The GC category is mainly aimed at urban gas transmission and distribution pipelines, including those in factories and residential areas. Although the pipelines are bounded by the factory perimeter wall, this does not mean that two sets of design standards and acceptance criteria are required. This is because the steam pipelines inside and outside the plant actually form an integrated thermal system, and its quality and safety require consistency. Therefore, design and acceptance should be carried out using unified standards. .
The steam pipes within the plant are classified as GC category.
According to the instructions in the standard specification “********* Example Version 3”: (1) The pipeline from outside the factory to the district heat exchange station falls under Category GB2; (2) Pipelines within the factory area are generally designed as Category GC pipelines per the specifications. If it is in accordance with GC within the factory perimeter, then this steam pipeline is divided into two sections at the boundary of the factory wall, with two sets of design standards and acceptance criteria. (3) The pipes within the plant area leading to the edge of the equipment can also be designed in accordance with GB2. Thus, there are one set of design standards and acceptance criteria for steam pipelines.
GC refers to industrial pipelines, GB1 refers to gas pipelines, and GB2 refers to thermal pipelines. The scope of thermal pipelines is specified in GB-T 38942-2020 Code for Pressure Piping – Public Pipelines