Use of Hole OpenersA hole opener is a fixed diameter bore hole enlargement tool that is utilized to expand the well bore beyond the original hole size drilled by the bit. HOC has many different types of hole openers to meet the various applications.
Function of Hole OpenersThe hole opener is generally used after the pilot bit has drilled the original hole. A hole opener consists of a body with roller cones or it could be a fixed blade that would be dressed with PDC or crushed Carbide.
Typical Application of Hole OpenersA hole opener is then tripped into the well bore to the beginning depth and then utilized to enlarge the pre-drilled pilot hole. This is the most typical, however, hole openers may be also utilized to ensure that the gauge of the pilot hole is intact, this method is generally known as a wiper trip. Wiper trips are best for deviated holes where trying to run the bit back to the end of the section could actually case a side track scenario in softer formations. Hole openers may also be utilized in the same drill string as the bit to perform a function of actually enlarging the well bore or ensuring that the bit gauge is maintained and clean up any formation beds that may accumulate throughout the section being drilled.
Key Features of Hole OpenersA hole opener is a cost effective way to enlarge a pre-drilled pilot hole or to ensure that the gauge is maintained in a deviated hole. A hole opener with a bull nose below helps to mitigate any potential side track issues in wiper trip applications.