American multinational oilfield services company Halliburton has released Stega™ advanced drill bit, to optimise the placement of backup cutters to improve bit durability without decreasing drilling efficiency or rate of penetration (ROP)
Halliburton explained that Stega™ bit focuses on avoiding some limitations that traditional backup cutters on polycrystalline diamond bits may have, including increased heat and wear, poor bit cleaning and reduced ROP.
In order to overcome these challenges, the company has designed the Stega bit with offset back-up cutters placed 180 degrees or more from the primary cutter. As a result, the new layout increases durability with less cutter wear and maximises drilling efficiency in contrast to traditional dual row or single row cutting structures.
“The development of Stega provides operators with the latest energy-efficient layout methodologies for targeted applications,” said Scott Regimbald, vice-president of drill bits and services at Halliburton.
Some of the advantages include an extended bit life with no loss of ROP to help operators drill longer and faster while reducing costs, Regimbald added.
With wearing of cutters, more engagement area is exposed to rock which, in turn, reduces cutting efficiency. A large portion of energy is wasted as friction from the increased contact area takes away from the bit’s ability to shear rock.
“Stega breaks this cycle by taking advantage of the bottom-hole pattern already created and removing load from the primary cutter before rapid acceleration of wear begins,” said Halliburton.
The oilfield company further explained that an operator in West Texas deployed the Stega bit in a harsh drilling application that historically used traditional non-Stega bit designs. The Stega bit drilled approximately 40 per cent further at an ROP that was 19 per cent per hour faster, thus resulting in valuable rig-time savings.
