Parts
MC450 Coring Unit. Operator’s Manual
© 2020 Utilicor Technologies Inc.
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ATTENTION
1. Accuracy: The 2 3/8" diameter PDC central pilot bit, which is integral to the Utilicor coring
process, acts as a concentric guide for the coring drum, centering and stabilizing it to ensure a
fast and accurate cut. It is the same type of robust, high-performance bit that is used in the
drilling industry to quickly and accurately cut through rock and other tough materials.
2. Access and Handling: The central pilot hole, created by the pilot bit, provides a convenient
access for the core-puller by which the core or coupon is removed from the pavement and by
which it is repositioned back into the pavement during reinstatement after completion of the
repair. Other coring processes which do not employ an integrated central pilot bit must either
drill a separate bar hole in the core, insert a separate lifting ring into the core or use some
form of clamping mechanism or other device to lift the core out of the hole after cutting and
to accurately refit the core back into the hole after the repair. This involves an extra step and
adds more complexity to the coring process.
3. Strength and Stability: The central pilot hole, when filled with Utilibond™ increases the
bonding surface of a typical 12" deep 18" diameter core by almost 100 square inches (a 13%
increase in bonding surface area) and adds strength to the reinstatement process. In addition
to increased surface bond strength, this central column of Utilibond™ acts as a continuous
stabilizing link between the replaced core and the Utilibond™ impregnated bed of pea gravel
at the base of the hole, increasing the vertical stability of the core as well as adding to the
overall strength of the reinstatement process.
4. Coring Guidance: Because the pilot bit cuts slightly deeper than the coring drum, it can
provide the coring operator with an audible and sensory cue as to when the coring drum is
about to core through the bottom of the pavement. When the pilot bit breaks through the
pavement into the sub-grade there usually is a noticeable change in the sound and the feel of
the coring process, which can alert the operator to the fact that the coring drum is about to cut
through the full pavement depth.
Utilicor Process, Pilot Bit and Integral Center Pilot Hole
The central pilot bit and related pilot hole, are unique to the Utilicor process, and
perform four important functions in Rotary Coring and Reinstatement:
