86 PROjECT PRIDE
a six-week time period instead of the estimated repair time
of 8–10 weeks by suppliers.
Initially, it was planned to use a 750 T crane for pre-heater
top structure and RABH chimney with boom combination
of 220 mtr (120 mtr main boom and 100 mtr luffing). But
during this period all main civil structures around pre-
heater were completed and hence it was very difficult
to accommodate this crane for operation due to space
constraint as this required 24 mtr X 24 mtr space between
blending silo and LS shed for operation. Immediately we
along with M/s Ayoki expert team start exploring for
alternate option and after brainstorming finally decided to
mobilize 650 T crane with a combination of 180 mtr boom
(90 mtr + 90 mtr), which can accommodate in that area and
can erect up to +170 mtr. Above this with 25 T tower crane
further erection was possible till +182 mtr height with its
full height up to +184 mtr.
The 650 T crane mobilized and operation started on 11
June 2019 and erected RABH module and then pre-heater
items. During its operation, we came to know full boom
combination could not be utilized due to technical issues
and finally with a combination of 90 mtr + 82 mtr (172 mtr)
boom, crane could erect up to +162 mtr level.
To increase the height and stability of tower crane, a
new fixing arrangement was done at +139.214 mtr level,
for which special supporting structure was fabricated and
erected at the pre-heater top.
Another challenge was with a lifting capacity of tower
crane, though it was 25 T capacity (with 4-fall) but due to