Here are the reminders and explanations regarding the key provisions of the \"General Specifications for Industrial Equipment and Pipeline Projects in Plant Areas\" (draft for comments)!

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Recently, the mandatory national standard for the entire industry, the \"General Specifications for Industrial Equipment and Pipeline Projects in Plant Areas\" (draft for comment), was released. There was strong reaction from within the industry, and some opinions were also shared in the 25 WeChat groups dedicated to pressure pipeline professionals; let’s take a look. This article is not a full excerpt or analysis of the entire text; rather, it highlights certain provisions that are useful for practical work and are not included in the standard guidelines, while also offering our suggestions and opinions. The writing was done in haste; please understand. Please cite the source when reproducing it. Chapter 1 1.0.4. This specification does not apply to long-distance pipelines, municipal gas pipelines and municipal heat pipelines, etc., nor to the pipelines associated with equipment or machinery designed as complete sets by manufacturers. Reminder: This article outlines the scope of application, which is limited to the design, construction, acceptance, modification, and demolition of GC-class pipelines (including non-metallic pipelines) as defined in the safety technical specifications for special equipment. It does not apply to GA, GB, and GD-class pipelines specified in the regulations, nor to the pipelines associated with equipment or machinery designed as complete units by manufacturers. 1.0.6. The design, construction, acceptance, operation and maintenance, as well as demolition of industrial equipment and pipelines in the plant area must comply with these specifications. When these specifications conflict with the provisions of **laws and regulations, or are inconsistent with more stringent mandatory standards, the provisions of the relevant laws, regulations, and such more stringent mandatory standards shall prevail** ； When the fire protection provisions in other special project construction standards conflict with or are lower than those in this specification, the provisions of this specification shall prevail. Chapter 2 2.0.1. The design, construction, acceptance, operation and maintenance, as well as demolition of industrial equipment and pipelines in the plant area shall meet the requirements for safe production and environmental protection. 2.0.2. The design, construction, acceptance, operation and maintenance, as well as demolition of industrial equipment and pipelines in the plant area shall follow the principles of advanced technology, economic rationality, and resource conservation; the use of materials that are explicitly prohibited or phased out is strictly forbidden. 2.0.3. During the design service life, the industrial equipment and pipelines in the plant shall comply with the following requirements: 1. The functional specifications and operating conditions specified for the equipment and pipelines shall not be altered without design approval or technical evaluation ； 2. When equipment and pipelines fail to meet the design requirements, they should be replaced, modified, or repaired promptly ； 3. In the event of disasters such as earthquakes, explosions, and fires, the equipment and pipelines used for post-disaster response should be inspected and evaluated, and actions should be taken in accordance with the results of that evaluation. Chapter 3 3.1.7. For pipelines carrying liquefied hydrocarbons, flammable gases, flammable liquids, as well as corrosive and toxic substances, they shall not be installed in a manner supported by buildings, except within the building(s) in which such pipelines are used. Reminder: This aspect is often overlooked in practical design and should be given due attention. 3.1.8. Piping for flammable media, liquefied hydrocarbons, and toxic media shall not pass through buildings that are not related to them, nor shall it be installed in poorly ventilated factories, inside indoor ceilings, or in enclosed mezzanines of buildings. Reminder: The gas accident that occurred somewhere at the beginning of this year may be an important factor in the formulation of these regulations. 3.1.10. For pipelines in environments free from explosion and fire hazards, static grounding shall be implemented if static electricity generated by them hinders production operations, affects product quality, or poses a risk of electric shock to humans. Reminder: Which pipelines require static grounding/bonding? Here’s why! This article written by us, who work in the field of pressure pipelines, is worth reading. 3.2.1. The design of pipelines for highly hazardous media shall comply with the following requirements: 1. When burial is required by the process, safety measures shall be in place to monitor for leaks, prevent corrosion, and collect harmful media ； 2. Manual valves installed on pipes carrying highly hazardous media within safety partitions or barriers should be equipped with valve extension rods, which lead to outside the partition or barrier for operation ； Reminder: Essentially, extreme caution should be exercised when laying any hazardous materials underground; the relevant standards should be reviewed repeatedly to ensure that safety measures are implemented. 3.2.16. When pipes carrying toxic, flammable, or asphyxiating media are laid in ducts, the following requirements shall be complied with: 1. Pipes carrying extremely hazardous and highly hazardous media shall not be installed in ducts that are accessible ； 2. Pipelines for flammable and asphyxiating media should not be installed in service trenches in the absence of reliable ventilation and safety measures ； Reminder: Essentially, extreme caution should be exercised when laying pipelines for any hazardous media, and the relevant standards should be reviewed repeatedly to ensure that safety measures are implemented. 3.2.18. Fracture-prone materials shall not be used for pipelines carrying extremely hazardous media. 3.2.19. The selection of pipeline components for pipelines carrying extremely hazardous media shall comply with the following provisions: 1. Valves with a reliable sealing design shall be used ； 2. When the valve cover of the valve is connected by flanges, at least four bolts shall be used. When a straight-thread connection with sufficient mechanical strength is used, the metal-to-metal contact sealing structure must be sealed by welding ； 3. Sliding sleeve flanges should not be used ； 4. The nominal pressure of the flange should not be lower than PN20 ； 5. When using a structure with straight threads and gaskets for sealing, a design should be chosen in which the sealing surfaces of the components do not undergo relative rotation either during tightening or after it ； 6. Brazed joints, bonded joints, expansion jointed joints, and filler-sealed joints shall not be used ； 7. Segmented gaskets should not be used inside the butt weld joint ； 3.2.20. The selection of pipeline components for pipes carrying toxic media shall comply with the following provisions: 1. High-silicon cast iron shall not be used ； 2. Valves that employ a reliable sealing design to prevent leaks at the valve stem packing should be used ； 3.2.21. The selection of pipeline components for pipes carrying flammable media shall comply with the following provisions: 1. High-silicon cast iron, lead, tin, and their alloy materials shall not be used ； 2. The selected soft-sealed valves should have a fire-resistant design ； 3. Brazed joints and bonded joints should not be used ； 3.2.22. Compensators with packing seals shall not be used for pipelines carrying toxic and flammable media. Suggestion: Given that GB/T20801-2020 and General Administration Document No. 2019-6 have been issued and are accepted by the industry, it is recommended that the definitions of highly hazardous media and toxic media should follow those in the 2015 version of the \"Catalogue of Hazardous Chemicals\"; clearly, the requirements here are copied from the 2000 (2008) version of GB50316. Regarding the standards for industrial pipelines, GB50316 constitutes a system, with earlier versions of ASME B31.1/31.3 serving as the main reference ； The SH (including GB50517) / DL (including GB50764) codes represent another separate system ； GB50235/50236 and the corresponding acceptance specifications represent an even newer system ； Of course, there is also GB/T20801, which was developed in conjunction with TSG. The author believes that, although each industry has its own characteristics, different industry standards serve unique purposes and have distinct goals. However, basic consistency should still be maintained in some fundamental definitions. Otherwise, in pressure pipeline projects, for a given medium, one should first refer to GBZ230, then the old standard GB5044, and possibly HG/T20660 as well; finally, the catalog of hazardous chemicals should be checked. Isn’t it exhausting for those working directly with pressure pipelines? Chapter 4 4.4.7 The pneumatic pressure test of pipelines shall comply with the provisions of relevant standards: 1. For pipelines in which it is not possible to fill them with liquid due to structural or support reasons, or where the operating conditions do not permit the retention of test liquid, a pneumatic pressure test is permitted, provided that the consent of the design unit and the construction unit is obtained. The pneumatic testing plan shall include effective and reliable safety measures, and must be approved by the technical supervisor of the construction unit. Warning: Pressure testing is extremely dangerous. It is still recommended to use the principle of \"who benefits shall bear the responsibility\" to clarify rights, obligations, and interests for this clause (replace \"and\" with \"or\"); otherwise, there will be many coordination issues. In other words, if the construction party believes there is an urgent need for a pressure test, then it only requires the consent and assumption of responsibility by that party; this approach helps to avoid the numerous disputes, delays, and decision-making difficulties that can arise during project construction. Chapter 5 5.3.2 Non-destructive testing can be carried out only after the visual quality of the pipe welds has been verified as satisfactory. Non-destructive testing shall comply with the following provisions: Article 3: The butt welds of the following pipelines shall be subject to 100% radiographic or ultrasonic testing, while the fillet welds shall be subject to 100% magnetic particle or penetrant testing: 1) Pipelines carrying fluids with an extremely hazardous toxicity level ； 2) Pipelines for flammable fluids and toxic fluids with a design pressure of 10 MPa or greater ； 3) Pipelines for flammable fluids and toxic fluids with a design pressure of 4 MPa or greater and less than 10 MPa, and a design temperature of 400°C or greater ； 4) Piping for non-flammable and non-toxic fluids with a design pressure of 10 MPa or greater and a design temperature of 400°C or greater ； 5) Pipes designed for temperatures below -20°C ； 6) Piping under severe cyclic conditions ； 7) Titanium and titanium alloys, nickel and nickel alloys, high-chromium-nickel-molybdenum austenitic stainless steels, zirconium and zirconium alloy pipes ； 8) Inner tube of the sleeve pipe ； 9) Other pipes specified in the design documents. Suggestion: Although GB/T20801-2020 also stipulates that high-chromium-nickel-molybdenum austenitic stainless steels require 100% radiographic or ultrasonic testing, and that fillet welds need to undergo 100% magnetic particle or penetrant testing, it is unclear whether such materials require a specific definition – even in the explanatory notes (for example, what percentage of alloy composition is required?) Perhaps there is; the author wrote in haste and didn’t see it), otherwise, haven’t you seen how many people ask on Baidu? Are the commonly used 316/316L/317/317L included?