In its first run in the Haynesville shale, Ulterra’s 6.75-in. UD511 bit set a new same-rig record for drilling a curve section, drilling the curve in 35 hours at a rate of penetration (ROP) of 23.4 ft/hr. The UD511 saved $33.5/ft compared to the fastest competitor offset.
The 5-bladed bit with 11 mm cutters was a departure from the typical drilling
program, in which 7-bladed, 11-cutter bits and 2-plus-degree bend motors have
been used to ensure steerability while achieving build rates necessary to hit the
target. Average penetration rates for the 7-bladed bits has been 12-15 ft/hr, although an Ulterra UD711 bit achieved a penetration rate of 20 ft/hr.
According to Chris Hearn, Application Engineer for Ulterra, the steel-body design
and short-gage configuration of the UD511 bit contribute to its superior performance.
“This bit was designed specifically for Haynesville curve and build sections,” he said. The 4.38-in. make-up length provides the shortest bit and ultimately the shortest bit-to-bend length currently available for Haynesville slim hole drilling.
The directional driller was enthusiastic about the UD511 bit’s performance and
commended its ability to hold toolface while achieving both necessary build rates
and record-setting ROP.
Ulterra is a leading provider of premium drill bits and downhole tools for the oil
and gas industry. Ulterra’s strength resides in the experience and wisdom culled
from industry veterans, designing high-quality, high-performance PDC bits for
global markets. Its small footprint, focused exclusively on drilling tools, provides
Ulterra the ability to respond quickly to customer’s specific applications with