Requirements for unloading mobile pressure vessels

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Regarding the requirements for unloading mobile pressure vessels: According to 1.5.4 Loading and Unloading Accessories in TSG R0005-2011, the loading and unloading accessories for mobile pressure vessels include loading and unloading valves, pipes for loading and unloading, quick-connect fittings, etc. 6.3 Pipes for Loading and Unloading: These pipes must meet the following requirements: (1) The connection between the pipes for loading and unloading and the mobile pressure vessel must be reliable； (2) There are safety measures to prevent the loading/unloading pipes from being pulled out ； (3) The material of the piping used for loading and unloading must be compatible with the filling medium; the inner surfaces of such piping that come into contact with oxidizing media such as liquid oxygen require degreasing treatment as well as measures to prevent grease contamination ； (4) The pipe materials used for loading and unloading frozen liquefied gas media can meet the low-temperature performance requirements ； (5) The nominal pressure of the loading and unloading pipes shall not be less than 2 times the operating pressure of the loading and unloading system, and their minimum burst pressure shall be greater than 4 times the nominal pressure ； (6) The filling unit or the using unit must conduct a pressure resistance test on the loading and unloading pipes every six months; the test pressure shall be 1.5 times the nominal pressure of such pipes, and the results of the test along with the signature of the person who conducted it must be recorded ； (7) The pipes for loading and unloading must be marked with the date of commencement of use, and their service life shall be strictly adhered to in accordance with relevant regulations. 6.4.2 Control of loading and unloading processes The work quality and safety during loading and unloading operations must meet the following requirements: (1) Personnel responsible for loading and unloading must hold relevant certificates and operate in accordance with the prescribed procedures; safety officers from the loading and unloading units shall conduct regular inspections ； (2) Park at the designated location; the engine of the tank truck must be turned off, the main power supply of the vehicle must be disconnected, and effective measures must be taken to prevent the vehicle from sliding ； (3) Before loading or unloading flammable and explosive materials, connect the static discharge device on the mobile pressure vessel to the grounding wire of the loading/unloading platform ； (4) The blind flange or equivalent device at the loading/unloading interface must be removed after the internal pressure has been released ； (5) Filling shall be carried out using the filling pipes dedicated to the filling unit; the filling pipes carried on the vehicle shall not be used for filling ； (6) The connection between the loading/unloading pipe and the mobile pressure vessel shall meet the requirements of the filling procedure, and such connection must be safe and reliable ； (7) Before loading or unloading media that cannot mix with air, perform pipeline purging or displacement ； (8) During loading and unloading operations, the operator must be in the designated position ； Where an emergency shut-off device is installed, the operator must be located at the remote control system for that device ； If a safety interlock alarm device for loading and unloading is installed, such device must be in good working condition ； (9) The pressure, temperature, and flow rate during loading and unloading must meet the requirements of the technical specifications and relevant standards applicable to the medium being handled; effective measures must be taken promptly if these parameters exceed the specified limits ； (10) The filling volume (or filling pressure) of mobile pressure vessels shall not exceed the approved maximum allowable filling volume (or filling pressure); overfilling or incorrect filling is strictly prohibited. I understand that the accompanying hose is a necessary safety accessory, but it cannot be used during filling; it can be used during unloading (when transferring from a mobile to a fixed pressure vessel). The entity using the vehicle is responsible for carrying out regular pressure tests on this hose. I’m not sure if my understanding is correct – please advise me, experts