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Preface: Pressure pipelines are one of the items subject to supervision and inspection in the manufacturing of special equipment (hereinafter referred to as supervision and inspection of special equipment). So, what are pressure pipelines? Under what scope of pressure pipelines is supervision and inspection by special equipment authorities required? 1. Definition of pressure pipelines 1.1 Definition of pressure pipelines in the “Catalogue of Special Equipment” On October 30, 2014, the General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China (as a result of institutional reforms by the State Council in 2018, this administration was merged into the newly established General Administration of Market Regulation) issued Announcement No. 114 of 2014 regarding the revision of the “Catalogue of Special Equipment”. According to the provisions of the “Law of the People’s Republic of China on Safety of Special Equipment” and the “Regulations on Safety Supervision of Special Equipment”, the General Administration of Quality Supervision, Inspection and Quarantine revised the “Catalogue of Special Equipment”; with the approval of the State Council, it is now promulgated and put into effect. At the same time, the \"Notice on Publication\" (Guo Jian Zhi Guo (2004) No. 31) and the \"Notice on Adding to the Catalogue of Special Equipment\" (Guo Jian Zhi Te (2010) No. 22) are repealed. The “Catalogue of Special Equipment” is interpreted by the General Administration of Quality Supervision, Inspection and Quarantine. This is to announce. In item 8000 of the catalog of special equipment attached to the announcement, the definition of pressure pipelines has been revised as follows: Pressure pipelines refer to tubular devices that use a certain pressure to transport gases or liquids. They are defined as those with a maximum operating pressure of 0.1 MPa (gauge pressure) or more, where the medium is a gas, liquefied gas, steam, or a liquid that is flammable, explosive, toxic, corrosive, and has a maximum operating temperature equal to or higher than its standard boiling point; furthermore, such pipelines must have a nominal diameter of 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. 1.2 In Part 1: General Provisions of the Code for Pressure Piping • Industrial Piping GB/T20801.1-2020, the definition of pressure piping includes the criterion that the nominal diameter is greater than or equal to 50 mm; however, this criterion does not apply to the internal pipes of boilers, pressure vessels, and heating furnaces, as well as to the external pipe connections of such equipment. 1.3 The industrial metal pressure piping referred to in this part (hereinafter referred to as “pressure piping”) includes those belonging to process units, auxiliary units, and utility systems within the designated area. This section applies to pressure pipelines that meet the following conditions: a) those with a maximum operating pressure of 0.1 MPa (gauge pressure) or more, in which the medium is gas, liquefied gas, steam, or a liquid that is flammable, explosive, toxic, corrosive, and has a maximum operating 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. b) Pressure pipelines other than those listed in 1.5. 1.4 This section does not cover the following areas: a) specific requirements for the modification, inspection, testing, maintenance, and repair of pressure pipelines in service; b) pipelines with a nominal pressure of PN420 or higher; c) non-metallic pipelines or their lining layers. 1.5 The areas where this section does not apply are as follows: a) Piping in equipment and nuclear facilities; b) Piping in devices used for the exploration and extraction of oil, natural gas, geothermal energy, etc.; c) Pressure piping in mobile equipment such as railway locomotives, automobiles, ships, and aerospace vehicles; d) Long-distance pipelines of type GA; e) Utility pipelines of type GB; f) Power pipelines of type GCD; g) Internal piping in boilers, pressure vessels, and heating furnaces, as well as external connection ports of equipment; h) Piping used for transporting non-toxic, non-flammable, and non-corrosive fluids, with a design pressure of less than 0.1 MPa (gauge pressure) but not lower than atmospheric pressure. 2. Pressure pipelines that require inspection 2.1 Article 2 of the Regulations on the Safety Supervision of Special Equipment, which came into effect on May 1, 2009, specifies that pressure pipelines subject to safety supervision under these regulations are those that are “related to life safety and pose a high degree of risk.” Article 2: The special equipment referred to in these regulations includes boilers, pressure vessels (including gas cylinders, the same hereinafter), pressure pipelines, elevators, lifting machinery, passenger cableways, large-scale amusement facilities, and specialized motor vehicles used within factories or premises, all of which are related to life safety and pose a high degree of risk. 2.2 The scope of application for supervision and inspection as specified in the \"Rules for Supervision and Inspection of Pressure Pipelines\" TSG D7006-2020 2.2 Scope of Application 2.2.1 Manufacturing supervision and inspection These rules apply to the supervision and inspection of the manufacturing process of the following pressure pipeline components within the scope specified in the \"Catalogue of Special Equipment\": (1) Submerged arc welded steel pipes, polyethylene pipes (Note 1-1); (2) Gas pressure regulating devices, temperature and pressure reducing devices, prefabricated pipe sections manufactured in factories (Note 1-2), flow meters (housings) (Note 1-3) that are part of component assembly systems. Note 1-1: Does not include polyethylene pipes with metal skeletons and fiber-reinforced polyethylene pipes. Note 1-2: Factory-prepared pipe sections refer to pipe components that are welded and assembled by the manufacturing unit in a factory according to the construction design drawings before being shipped as complete units; this does not include pipe preparation carried out by the installation unit at the construction site. Notes 1-3: The temperature and pressure reduction devices used in the pipes within the boiler area, the prefabricated pipe sections, and the flow meters (housings) can be manufactured and inspected in accordance with the relevant regulations for boilers. 2.3 Document No. [2018] 515 issued by the Market Regulation Authority provides a clear definition of \"pipes within the scope of power station boilers\"; such pipes include the boiler’s main feedwater pipes, main steam pipes, reheat steam pipes, etc. The main feedwater pipeline refers to the main feedwater pipeline from the outlet isolation valve of the boiler feedwater pump (valves are not included, the same below) to the economizer inlet header, as well as the branch pipelines up to the primary valves. The main steam pipeline refers to the main steam pipeline from the outlet of the final superheater in the boiler (or from the steam collection box, if one is present) to the high-pressure main steam valve of the turbine, as well as the branch pipelines within the primary valves. For power station boilers operating with a main steam header, this refers to the branch pipes up to the main steam header and the primary valves. The reheat steam pipeline includes the reheat steam cold section pipeline and the reheat steam hot section pipeline. The reheat steam cold section pipes refer to the reheat steam pipes from the turbine exhaust check valve to the reheater inlet header, as well as the branch pipes up to the primary valves. The reheat steam hot-section pipes refer to the reheat steam pipes from the outlet of the boiler’s final stage reheat steam header to the medium-pressure main steam valve of the turbine, as well as the branch pipes within the primary valves. In other words, the ‘Special Equipment Manufacturing License’ cannot be abused just because it involves pressure pipelines, especially by users on the external network who are not ‘primary valves’. Summary: The components that come into frequent contact with our products and require supervision and inspection fall within at least the following categories: (1) Those specified in the \"Catalogue of Special Equipment\" ； (2) Within the scope of power station boilers, it is not subject to the restriction that the nominal diameter of the pipeline must be 50 mm or greater ； (3) In other cases, pipes with a nominal diameter of 50 mm or greater.