THE EFFECTS AND CAUSES OF BOILER TUBES FAILURES ON EFFICIENCY OF POWER PLANT

Abstract

In this study the failure of the boiler tubes of the (KNPS, 6x380MW) investigated, also analysis the effects of boiler tube failure on efficiency of (KNPS). The experimental methods used to test and analysis of boiler tubes samples, to knowing reasons of tubes failure frequent in (KNPS) and behavior of this samples, there are five experimental methods selected to inspection of boiler tubes (new samples and failed samples), and comparison the result by (ASME&ASTM Standard),The experimental result show that, differentiated values between these two specimens after test, from this method Visual examination (Naked eye, Digital camera),and Dimensional measurement(inside calipers, outside calipers), Show The outer diameter (OD) and Inner diameter (ID) and Wall Thickness (WT).And Chemical Composition examination and Mechanical Properties measurement show the mechanical property of the two samples tubes were examined by using tensile test and Hardness Test. The experimental results, of tensile test including yield stress (YS), ultimate tension stress (TS), and elongation (ε), while the Hardness Brinell test got the average value of hardness, And Bore scope inspection show internal surface of boiler tube All details of this result existed in chapter four The effect of forced outage of boiler by reason of boiler tubes failure ,leads to reduction in power generation and hence reduction in plant load factor(PLF) and increased oil consumption due to multiple cold start sup of boilers, and also effect on availability of units.