Floating casing technology is a technique specifically designed for casing operations in large displacement wells and horizontal underground wells. This technology utilizes floating couplings to act as temporary barriers throughout the entire casing string. Due to the sealing of the casing between the floating coupling and the floating shoe with air or low-density drilling fluid, the positive pressure of the lower pipe string (below the floating coupling) on the wellbore is reduced, thereby reducing the frictional resistance during the descent. By injecting drilling fluid into the casing above the floating coupling to increase the weight of the upper string and push the string downwards, the entire string can be safely and smoothly lowered
Characteristics of floating coupling technology:
Simple structure, easy to install, effectively isolating floating section and grouting section
The rupture disk adopts a pressurized crushing working mode, with a relatively accurate rupture pressure (± 2MPa), and the rupture pressure can be adjusted
After the rupture disk is broken, the degree of fragmentation is high, and the broken particle size is less than 8mm, which is easy to pass through the float hoop and float shoe
