Standard Technical Features of BTG System for Supercritical 660 ...

Standard Technical Features of BTG System for Supercritical 660/800 MW Thermal Units8.6.7 Calculated static loading of each support of the PC pipes shall be increased byat least 25% to arrive at the design load, to take care of the shock loadingoccurring in the pipe work under abnormal conditions of operation.8.6.8 The guide plates, wherever provided in the coal pipe, shall be removable, andaccess to them shall be obtained through detachable cover. The guide platesshall be made up of suitable abrasion resistant material.8.6.9 Coupling and toggle section arrangement for fuel piping shall be provided totake up the furnace expansion.8.6.10 The following PC pipe portions shall be ceramic lined with ceramic thicknessof not less than 15 mm:i) From mill outlet to first bend and two times pipe diameter straight lengthdown stream of first bend.ii) All bends between 15 0 & 30 0 angle and straight length downstream of thebends equivalent to one pipe diameter.iii) All bends of 30 0 and higher angle and two times diameter straight lengthdownstream of the bend.iv) The burner inlet elbow and the pipe piece after the elbow. PF pipe frommill to the classifier (in case of separate classifier).8.6.11 The pipe/ bend base material thickness, wherever ceramic liners are provided,shall not be less than 8 mm.8.6.12 The straight unlined PC pipe length shall be of mild steel having a thicknessnot less than 13 mm with a minimum wear allowance of 4 mm.8.6.13 Ceramic material shall be Alumina content of not less than 90% andguaranteed life 25000 hrs (minimum).8.6.14 Suitable devices shall be provided in each pulverized coal pipes to enable onloadadjustment for equalizing flow.8.6.15 Purge air connections shall be provided after the mill outlet valve to cleanpulverized coal pipes of any deposits etc.8.7 Coal Burners8.7.1 Coal burner designi) Turn down ratio of coal firing system 2:1 (minimum).69