pipe weld procedure
Repair welding, review and approval.Before welding, the work plan and safety measures shall be determined according to the specific content of the work, and the approval procedures (such as hot work approval, pot operation approval, etc.) shall be handled at the same time.
(1) most chemical production equipment and containers are connected by pipelines. When welding workers enter containers and pipelines without displacement ventilation or isolation, they will be poisoned.(2) the container pipeline for cleaning and replacement is a hypoxic environment. When welders work in it, suffocation will be caused by hypoxia.(3) when welding and cutting the equipment pipelines with degreasing, painting or polytetrafluoroethylene and polypropylene gaskets, these paint films, gaskets and residual materials evaporate or crack under high temperature, forming toxic gas and toxic steam, which are poisoned after inhalation.(4) due to the narrow working space on the maintenance site, more adverse factors for maintenance, and some welding processes produce more asphyxiating gases, or photochemical reactions due to arc light produce carbonyl nickel, phosphine, phosgene, etc., poisoning may occur due to poor ventilation.(5) toxic gas or steam emitted from the cracks to be repaired when pressure is not replaced when the container pipes containing or delivering toxic media are used, which may easily cause poisoning accidents if not properly protected.