Procedure of annual inspection of boiler for renewal of certificate as per Indian Boiler Regulation
The preparation for annual statutory inspection is mainly consisting of gradual cooling and opening up of the boiler and thorough cleaning of the fire side and water side surfaces. If possible the boiler is allowed to cool down naturally and the water is removed only after the brickwork is sufficiently cooled to avoid any damage to the boiler due to temperature differentials. If the Boiler under inspection is working in battery with other boilers, it must be effectively disconnected of all steam and hot water communications with other boilers under steam. Effective disconnection shall be made either by removal of the boiler stop valve or of a length of piping, or by the insertion of substantial blind flanges between the boiler stop valves and piping.
Remarks mentioned in the certificate of the Boiler issued by the Government Inspector should be carefully perused and if there are any requirements for removal of lagging, brickwork etc. are mentioned, then the same should be complied with. Water must be drained through blow down system. After the boiler has cooled man hole covers of the main drum must be opened first. If the bottom man hole covers are opened first there is likelihood of injury to personnel due to escaping steam or hot air. All doors of man, mud and sight holes, cleaning plugs, all caps of headers and mud drums, fire bars and their bearers, fire bridge arches, oil or gas fuel burners, mechanical stoker attachment etc. is to be removed, and then the cleaning attended to.
Any horizontal tube from which water can be drained should be cleaned of water. All tubes cleaned internally by brushing or cleaned tool.
All boiler components must be cleaned thoroughly. If the scale from the boiler components can not be removed, by mechanical cleaning, chemical cleaning must be restored to, which must be attended to by experts. Before entering a boiler, it must be ascertained that it is isolated from other boilers under steaming condition. All steam drum internals are to be removed for cleaning.
After the boiler is thoroughly cleaned and attended, the boiler must be offered for inspection. A powerful torch or if available, a portable lamp of 24 volts or less should be made available for internal inspection.