The process of hole enlargement consists of positioning a hole enlarger tool above the drill bit to increase the diameter of the hole, either while it is drilled or in a successive operation.
Hole enlargement operations can be challenging. As the drill bit and enlarger drill through different rock types, their drilling speeds can vary. As a result, the loads on both the bit and the enlarger are constantly changing in different proportions, impacting on their combined performance.
Using two NeoTork tools on the drill string will help balance the loads.
Located in the BHA, the first NeoTork will reduce slip and stick, compensating for any slack in the BHA caused by an increase in the speed of the enlarger.
Positioning the second NeoTork above the enlarger will stop it from stalling or vibrating when it encounters a load peak, for example due to the bit drilling faster, a too large slack from the surface or from going through a change in the nature of the formation.
NeoTork smoothens torque and weight transfer, which reduces vibrations and protects both bit and hole enlarger, as well as all other drill string components.