Bench tests for milling 4 windows from one level in the section of casing with a diameter of 139.6 mm made of high-quality steel (C95) were carried out. During the tests, the Perfobur layout with a 75 mm mill and a special slim mud motor were used.
The length of the milled “window” is up to 800 mm;
The average milling time is 7.5 hours;
The average penetration rate is 8.1 cm / h.