Must a pressure vessel be equipped with a safety valve? Which standard specifies it?

They’re all called pressure vessels – how can there be any without safety valves? Lol; the regulations are more stringent than you think

B1.2 For the relief devices installed on the connection pipelines of pressure vessels, is it possible to omit safety valves on the pressure vessel itself?

Generally, for pressure vessels that do not come equipped with safety devices, a clause is added to the technical specifications in the drawings stating that the safety accessories shall be installed by the user within the system； For example: Technical requirements 1. The pressure-bearing components and welding materials must come with quality certificates and comply with the relevant material standards ； 2. The welding materials shall comply with NB/T 47018-2017 \"Technical Requirements for Ordering Welding Materials for Pressure Equipment\"; 3. The types and dimensions of welding joints shall be in accordance with those specified in HG/T 20583-2011. The size of the fillet welds where not specified shall be based on the thickness of the thinner plate, and the welding of flanges shall follow the provisions of the relevant flange standards ； 4. For the AB-type joints contained within the circles with the center of the opening as the center and the diameter of the opening as the radius at each outlet, 100%-RT testing shall be carried out in accordance with NB/T47013.2-2015, and a grade II result is considered acceptable. 5. The medium used for the hydraulic test is clean water, and the temperature of this medium must be at least 5°C. The specific requirements are specified in clause 11.4.9 of GB/T150.4-2011. 6. The inner surfaces of the equipment must be smoothly polished, without any edges or burrs, to ensure cleanliness inside the equipment ； 7. After rust removal from the external surface of the equipment, apply red epoxy resin as an anti-rust coating ； 8. The flange bolt holes are evenly distributed across the mid-span. 9. The nameplate is installed by the manufacturing unit; 10. Safety accessories are configured uniformly by the user within the system ； 11. Lugs are intended only for lifting the empty weight ；

1. In LZ’s question, there is a keyword called “must”; this word indicates a negative outcome, meaning that domestic regulations (such as the Safety Technical Inspection Regulations for Fixed Pressure Vessels) and standards (GB150) do not impose any mandatory requirements in this regard. 2. The appendix to GB150 provided by the friend on the second floor contains clear explanations in the underlined sections that answer the question. 3. As for whether safety devices such as safety valves should be installed on the vessel, the official wording is “install overpressure relief devices in accordance with design requirements”; in simpler terms, it depends on the design specifications. 4. There are conditions under which safety valves need not be installed on the pressure vessel itself; the following conditions must be met simultaneously: 4.1. The pressure source comes from outside the pressure vessel; 4.2. The external pressure can be reliably controlled. 5. Of course, using a vessel designed for ultra-high pressures in a low-pressure environment means that there is no need to consider installing safety valves at all

Is Article 1 of Clause 5.5.1 of the Petrochemical Regulations considered a basis for requiring pressure vessels to be equipped with safety valves? ?

1 I don’t have any relevant information available; please provide the specific name so that I can look it up and then discuss it with you. 2 There is a hierarchical system of standards for pressure vessels in China, which is divided into several levels: 2.1. The first level is the Special Equipment Safety Law, which represents the legal framework. 2.2. Second level: Regulations on the safety supervision of special equipment. 2.3. Third level: Rules and regulations issued by the General Administration of Quality Supervision, Inspection and Quarantine. 2.4. Fourth level: Technical regulations for the safety of special equipment, such as the commonly used \"Technical Regulations for the Safety Supervision of Fixed Pressure Vessels\". 2.5. Fifth level: Standards or industry norms cited by relevant laws and regulations, such as \"GB150 Steel Pressure Vessels\", which is a core standard in the pressure vessel standard system. 3. The references cited in this topic fall under the fourth and fifth levels; as for whether there are higher-level standards that contain specific details, it is recommended to check those as well.

Code for Fire Protection Design of Petrochemical Enterprises, 5.5.1: Under abnormal conditions, safety valves shall be installed on the following equipment that may experience overpressure: 1. Pressure vessels with a maximum operating pressure at the top of ≥0.1 MPa

1. According to the description in clause 5.5.1 provided, a maximum pressure at the top exceeding 0.1 MPa means that the equipment meets one of the conditions for being considered a pressure vessel; however, whether it is necessary to install such a device is indicated as \"possible overpressure\" in the preceding text. What if it has been determined that overpressure is impossible during use? 2. The terminology used in standard specifications is precise; it is necessary to read the entire content when using such specifications. 3. I just saw the answer provided by a friend on floor 8, which used the word “must” – quite interesting. 4. In fact, if people are using petrochemical-based materials in construction, it is quite common to see heat exchangers, which are one type of pressure vessel, without safety valves installed on them. 5. To understand one sentence in the specifications: if the pressure source is external to the pressure vessel and the pressure is controllable, it is possible to determine whether it is necessary to install a safety valve on the vessel itself