
Engineered for the most extreme large-diameter drilling programs in the 18"–24" / 457–610 mm bit range. Heavy-duty SD18 shank, 717 lb / 325 kg hardened piston — the most powerful in the Drill King lineup — at 1,100 blows per minute.

The HADK-185 is Drill King International’s ultra-class DTH hammer, engineered for the most extreme large-diameter drilling programs in the 18″–24″ / 457–610 mm bit range. Built on the heavy-duty SD18 shank standard, this single-model class delivers maximum impact energy at 1,100 blows per minute through a 717 lb / 325 kg hardened piston — the most powerful piston in the Drill King product lineup and purpose-built for formations that demand the highest energy per blow.
At 3,653 lbs / 1,657 kg and 16.30″ / 415 mm outer diameter, the HADK-185 operates in a class where drill string weight, compressor capacity, and rotary drive capability must all be matched to the hammer’s specifications. The 8⅝” API REG BOX top sub connection — a box-end configuration that distinguishes the HADK-185 from all smaller Drill King models — combined with a 12,000 lb·Ft make-up torque and 10,000 lb·Ft rotation torque rating reflects the extreme mechanical requirements of 18-inch class drilling assemblies.
Operating in a lower working pressure window (100–200 PSI / 7–14 Bar) than smaller-class hammers, the HADK-185 is optimized for compressor configurations typical of ultra-large-diameter programs. Premium alloy construction, a precision heat-treated hardened piston, and a dual-bearing design (upper and lower bearings) ensure sustained performance on the most demanding remote drilling sites worldwide.
Heavy-duty shank engineered specifically for the extreme torque, weight, and impact demands of 18-inch class drilling assemblies.
A 717 lb / 325 kg hardened piston — the heaviest in the Drill King lineup — delivers maximum energy per blow for penetration in the hardest, most competent rock formations.
18"–24" / 457–610 mm bit diameters — the widest bore range in the Drill King DTH series, covering ultra-large-diameter mining, geothermal, and civil drilling programs.
1,100 blows per minute of sustained high-energy impact across the full 18"–24" bit range.
12,000 lb·Ft / 16,272 N·m make-up torque and 10,000 lb·Ft / 13,560 N·m rotation torque for extreme mechanical demands.
Box-end top sub connection — unique among Drill King models — matched to heavy-duty large-diameter drill string configurations used in 18-inch class programs.
100–200 PSI / 7–14 Bar operation, matched to compressor configurations and rotary drive capabilities typical of ultra-large-diameter programs.
Dual upper bearings (×2, HPDK18520U) and dedicated lower bearing (HPDK18520L) for enhanced load distribution and extended bearing service life under extreme radial loads.
The 717 lb hardened piston, 1,100 BPM frequency, and 18"–24" bit range suit the widest blast-hole diameters, raise bore pilot holes, shaft sinking support, and deep hard-rock open-cut programs.
Penetration energy, dual-bearing durability, and matched air consumption for geothermal and deep municipal/industrial water wells requiring 18"–24" bore diameters.
Maximum energy per blow and sustained 1,100 BPM output for wide-bench quarry programs in granite, basalt, dolerite, and other high-strength aggregates.
Large-diameter foundation piles, bridge caissons, tunnel portal bores, culverts, and deep anchor programs requiring 18"–24" hole diameters.
| Specification | Value |
|---|---|
| Piston Weight | 717 lbs / 325 kg |
| Application Bit Range | 18" – 24" / 457 – 610 mm |
| Working Pressure | 100–200 PSI / 7–14 Bar |
| Outer Diameter | 16.30" / 415 mm |
| Hammer Weight | 3,653 lbs / 1,657 kg |
| Effective Length | 78" / 1,981 mm |
| Rotation Speed | 5–15 RPM |
| Frequency | 1,100 BPM |
| Top Sub Connection | 8⅝" API REG BOX |
| Make-Up Torque | 12,000 lb·Ft / 16,272 N·m |
| Rotation Torque | 10,000 lb·Ft / 13,560 N·m |
| Shank Connections | SD18 |
| Pressure (PSI) | Pressure (Bar) | CFM | M³/Min |
|---|---|---|---|
| 100 | 7 | 1,640 | 46.40 |
| 150 | 10.50 | 2,340 | 66.20 |
| 200 | 14 | 3,160 | 89.50 |
| No. | Part Name | Qty | Part Number |
|---|---|---|---|
| 1 | Top Sub | 1 | HPDK18502 |
| 2 | Washer – Top | 1 | HPDK18504 |
| 3 | Top Sub O-Ring | 1 | HPDK18503 |
| 4 | Check Valve | 1 | HPDK18507 |
| 5 | C.V. Spring | 1 | HPDK18509 |
| 6 | Spacer Ring | 1 | HPDK18505 |
| 7 | Disc Spring Set | 1 | HPDK18506 |
| 8 | Air Distributor | 1 | HPDK18510 |
| 9 | Air Dist. O-Ring | 1 | HPDK18511 |
| 10 | Cylinder | 1 | HPDK18512 |
| 11 | Piston | 1 | HPDK18514 |
| 12 | Wear Sleeve | 1 | HPDK18501 |
| 13 | Upper Bearing | 2 | HPDK18520U |
| 14 | Snap Ring | 1 | HPDK18515 |
| 15 | Bit Ret. Ring | 1 | HPDK18518 |
| 16 | Bit Ret. Ring O-Ring | 1 | HPDK18519 |
| 17 | Lower Bearing | 1 | HPDK18520L |
| 18 | Drive Sub Washer | 1 | HPDK18524 |
| 19 | Drive Sub | 1 | HPDK18522 |
| — | Choke Set | 1 | HPDK18508 |
| — | Complete Hammer | — | HADK-185 |
Contact Drill King International today — including compressor sizing guidance specific to 18-inch class programs.
Built tough enough for the unpredictability of job sites, our equipment minimizes costly downtime and re-drills.
Every hole counts, and our tools are built to keep penetration rates high even in unpredictable, mixed formations.
Engineered for open-pit and underground alike, our tools lower per-meter drilling costs without sacrificing performance.
Engineered for the rigors of well-site conditions, our hammers and bits extend service life while reducing per-foot drilling costs.
Less downtime, fewer bit changes, more material moved. That's the Drill King difference for quarry operators who can't afford to slow down.
From residential wells to large-scale geothermal fields, our tools are trusted to get the job done right the first time