The job at hand
- To completely remove the industrial chimney stack that was running 150 feet tall from ground level, parallel to the building structure. In fact, the chimney was taller by 30 feet.
- To scrap the dismantled chimney, structure and fixtures that were attached to the building wall.
Challenges
The height of the industrial chimney stack was 150 feet and the total weight of the industrial chimney was approximately 8 MT, including a support structure. To scrap it down to zero was a challenge in itself.
The additional jetting out of the factory chimney stacks 30 feet above the parapet level was posing a serious access challenge.
Solutions
Three different work-at-heights system were used:
- Industrial Rope Access System
- Prefabricated Cantilevered Steel Structure (Canti-Structure) was created
- Terrace Jibs (TJ) were created
TJ systems with pulley arrangement were prefabricated at the factory level and installed at the site parapet level, so that all canti-structure materials required can be lifted and moved to the terrace at 120 feet level. Thereafter, the canti-structure was installed using MS fabricators.
The, Industrial Rope Access Professionals got down through the cantilevered structure and started rigging the industrial chimney stack at every 1 metre level and started cutting the chimney through gas cutting and wherever required through AG-4 machines.
The jetting out part was thus accessed using the canti-structure and chopped down through gas cutting and carefully lifted and lowered down through the pulley rigged to the canti-structure. The process continued till the entire factory chimney was taken down.
Then, the canti-structure was dismantled and scrapped at the site level itself. All brackets and anchors fastened to the walls were removed. The whole chimney and canti-structure were scrapped at the site level and residue value realized by the client. TJ system was brought back to our factory.
This is how the entire 150 feet and 8 MT Industrial Chimney stack along with the structure were chopped down by Team Glass Hoppers.