PREPARATIONS
The uptakes should be checked; any dampers should be operated and then correctly positioned All vents, alarm, water and pressure gauge connections should be opened The superheater circulating valve or drains should be opened. All the other boiler drains and blow-down valves should be checked. The boiler should then be filled to slightly below the working level with hot de-aerated water. The various header vents should be closed. The economiser should be checked. The operation of the forced draught fan should be checked and exhaust gas air heaters if any should be bypassed.The fuel oil system should be checked for correct positioning of valves. The fael oil should then be circulated and heated, RAISING STEAM The forced draught fan should be started and air passed through the furnace for several minutes. The air slides (checks) at every register except " the lighting up" burner should then be closed. The operating burner should then be tit and adjusted. The fuel oil pressure and forced draught pressure should be matched. The superheater header vents may be closed once steam issues from them. When the drum pressure is about 210 К Pa (2: 1 bar) the drum air vent may be closed. The boiler must be brought slowly up to the working pressure. The main and auxiliary steam lines should now be wanned through and then the drains closed. The water level gauges should be blown through and checked for correct reading. When the steam pressure is about 300 k Pa (3 bar) below the normal operating value the safety valves should be lifted and released using the easing gear. Once at operating pressure the boiler may be put on load and the superheater circulating valves closed. All other vents, drains and bypasses should then be closed. The water level in the boiler should be carefully checked and the automatic water regulating arrangements observed for correct operation. (2300) TEXT 5 IRREGULARITIES IN OPERATION, CAUSES AND REMEDIES WORDS AND EXPRESSIONS
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