Zafar , Our Fertilizer Plant Annual Turnaround started. We have got lot of jobs including the two 90mm thick Carbon Steel blind flanges. 24 number of holes . The final hole size is 50mm. Holes being drill in 04 steps:
1- Centre Drill
2- 20mm Drill
3- 40mm drill
4- 50mm drill
The step one and two completed in 3hours... The third round in progress..I hope i will get all hole drilled in night shift.. I sent you zip file of videos and pictures.. i will post the final pictures of finished part tomorrow.