1 Reduce the load to 300 MW & then remove from CMC
2 Keep 4 consecutive Mills in service. If required , take oil guns in service
3 Before Unloading PA Fan (to be stopped ),The following Permissive & Protection to be kept bypassed :
“PA Fan ON & Discharge Gate close” permissive to be given
“PA Fan ON & Discharge gate auto open” to be bypassed.
“PA Fan ON & Discharge gate close” protection to be bypassed
4 Start reducing slowly the blade pitch of PA fan to be stopped. Monitor its suction flow & current. While reducing blade pitch , PA header pressure is to be closely monitored.
5 Monitor loading of other PA Fan in auto. Monitor its current. (Rated current of PA Fan is 211 A)
6 If PA header pressure is not maintaining , one Mill can be stopped after taking oil gun at one elevation.(Only 3 Mills will be in service )
7 Raise PA header pressure to 950 mmwc
8 Reduce PA Fan (to be stopped ) blade pitch to minimum (< 5 % )
9 Give close command to discharge gate. As soon as discharge gate close feedback came ,Stop PA Fan. During Discharge gate closing , keep in continuous communication with local operator
10 Keep one Mill pop up ready to trip in case PA header pressure shows alarming downward trend.
11 Normalise the permissive & protection which is kept bypassed above in S.No 3
12 Keep watch on PAPH Air/Flue gas temperature due to flow imbalance
13 Take 5th Mill if PA header pressure is OK & raise load
2 Keep 4 consecutive Mills in service. If required , take oil guns in service
3 Before Unloading PA Fan (to be stopped ),The following Permissive & Protection to be kept bypassed :
“PA Fan ON & Discharge Gate close” permissive to be given
“PA Fan ON & Discharge gate auto open” to be bypassed.
“PA Fan ON & Discharge gate close” protection to be bypassed
4 Start reducing slowly the blade pitch of PA fan to be stopped. Monitor its suction flow & current. While reducing blade pitch , PA header pressure is to be closely monitored.
5 Monitor loading of other PA Fan in auto. Monitor its current. (Rated current of PA Fan is 211 A)
6 If PA header pressure is not maintaining , one Mill can be stopped after taking oil gun at one elevation.(Only 3 Mills will be in service )
7 Raise PA header pressure to 950 mmwc
8 Reduce PA Fan (to be stopped ) blade pitch to minimum (< 5 % )
9 Give close command to discharge gate. As soon as discharge gate close feedback came ,Stop PA Fan. During Discharge gate closing , keep in continuous communication with local operator
10 Keep one Mill pop up ready to trip in case PA header pressure shows alarming downward trend.
11 Normalise the permissive & protection which is kept bypassed above in S.No 3
12 Keep watch on PAPH Air/Flue gas temperature due to flow imbalance
13 Take 5th Mill if PA header pressure is OK & raise load
No comments:
Post a Comment