Industries we serve
HORIZONTAL DIRECTIONAL DRILLING EQUIPMENT
CENTER ROCK INC.® designs and manufactures reliable horizontal directional drilling (HDD) equipment and tooling built for rock conditions that stop conventional bores cold. Our HDD product lineup includes the HDD LP DRILL® pull-reamer, ranging from 12″ to 60″ (305mm–1524mm) with custom sizes available, and the HDD Mono-Hammer, a steerable rock hammer built for pilot-hole drilling from 4.75″ to 12″ (120.5mm–305mm).
HDD LP DRILL® and Mono-Hammer Systems for Trenchless Rock Crossings
Horizontal directional drilling exists because contractors need to cross roads, rivers, rail lines, and utility corridors without tearing up the surface. That advantage disappears the moment a bore hits rock the tooling can’t handle. As a manufacturer of purpose-built HDD hammers and reaming systems, Center Rock gives HDD contractors the ability to hold a bore path and finish the crossing without switching methods mid-job.
The HDD Mono-Hammer handles the pilot hole, steering through rock and clay with wireline compatibility and standard sonde housings, including Ditch Witch® transmitters. Once the pilot hole is set, the HDD LP DRILL® opens it to full diameter in a single pass. It’s built as a canister of individual hammers, each one pneumatically driven and impacting its own bit, pulverizing rock into cuttings that clear back through the annular space around the drill pipe. No second pass. No wasted rig time.
Key Equipment Features:
- Steerable pilot-hole drilling in rock, clay, sand, and cobble
- Single-pass reaming from pilot diameter to full bore diameter
- Capable of pulling or pushing
- Built-in canister stabilization for precise bore control
- Side protection carbide inserts for extended wear life
- Capable of trailing casing with swivel
- Low vibration operation, no shock sub required
- Low torque and low air requirements
- Wireline adaptable, accepts standard 15″ and 19″ sondes
- Easily adaptable to any HDD drill rig on the market
What Makes HDD Drilling Demanding
A pilot hole has to hold its line from entry to exit, and rock makes that harder to guarantee. Miss the trajectory and a contractor risks striking an existing utility, missing the planned exit pit, or coming up short on a river or road crossing that can’t simply be redone. A hammer that drifts off course in a mixed formation turns a planned crossing into a lost bit and a lost day. Steering has to stay just as predictable in rock as it does in clay, from the first foot to the last.
Geotechnical reports are estimates, not guarantees, and contractors frequently plan a bore through soil only to hit an unexpected rock lens halfway through. Tooling built for a single ground condition can’t finish that job. It either stalls out entirely or forces the crew to pull the string and switch methods mid-bore, both of which cost time nobody budgeted for. Equipment able to transition from soil to rock without a change in method is what keeps the crossing, and the schedule, intact.
Reaming a bore from pilot diameter to full diameter in multiple passes is inefficient by design. Every additional pass means another trip down the hole, more wear on the tooling, and more rig time billed against a job that was quoted assuming a clean run. A reaming system built to open the hole in a single pass, without sacrificing bore integrity, is what keeps a directional crossing profitable instead of a change order.
OUR PRODUCTS
Tools for All of Your HDD Drilling Requirements
Horizontal Directional DRILLING
Products and Services
Center Rock supports HDD contractors with purpose-built pilot hammers, reaming systems, technical expertise, and field support. Between our tooling and our engineering team, we can get your bore through rock without a change in method.
Drilling Equipment:
HDD LP DRILL® Pull-Reamers
HDD Mono-Hammer Pilot Drills
RF Series Valved Hammers
ROCK XTREME® RX Series Hammers
HDD-Specific Slant-Face Bits
Support Equipment:
Portable Compressors
Oil and Chemical Injection Systems
Water Injection Systems
Hydro-JAW® Breakout Systems
Repair, Reconditioning, and Technical Support
Hammer and Bit Service and Repair
DTH Hammer Reconditioning
Bit Reconditioning and Recarbiding
Drilling Solution Consultation
In-House and On-Site Training
On-Site Consulting and Technical Support
Three Major Challenges Define Horizontal Directional Drilling
STEERING ACCURACY:
A pilot hole that drifts off line doesn’t just miss the exit point. It risks striking an existing utility or missing the crossing entirely. Steering control through rock has to hold from entry to exit.
MIXED GROUND TRANSITIONS:
Soil bores that hit an unexpected rock lens stall out fast. Equipment built for one ground condition often can’t finish the job in another, forcing a method change mid-bore.
SINGLE-PASS REAMING:
Multiple reaming passes burn schedule, fuel, and margin. A bore that has to be opened in stages instead of one clean pass turns a one-day crossing into a three-day one.
Getting these three right is the difference between a bore that goes in clean and one that turns into a change order.