Geothermal Drilling Rig Solutions: Deep, Ultra-Deep & Hot-Dry-Rock Wells
Geothermal Drilling: The Deeper, Hotter and Harder Challenge
Geothermal development pushes drilling into conditions that ordinary rigs were not built for. Targets run to 3,000-4,000 m and deeper; bottom-hole temperatures in hot dry rock can reach 158°C and beyond; and the formations themselves are hard granite, basalt, abrasive interbedded sediment and fractured fault zones that punish penetration rates, seal life and wellbore stability.
A geothermal drilling rig therefore has to solve three problems at once: hoisting heavy casing and long drillstrings at depth, breaking hard and abrasive rock fast enough to hold a schedule, and surviving high temperatures and unstable intervals without losing the hole.
CORTECH® fielded this exact combination. Geothermal work is a standard configuration across the whole CMD large-diameter series — the truck-mounted CMD100, the CMD130, the crawler CMD130L and electric CMD130DL, and the modular CMD150 and CMD180 platforms. The three models with the most recorded geothermal deployments are the CMD100 for hard-rock air DTH exploration holes, and the CMD150T and CMD180T modular variants for deep staged production wells and 160°C hot-dry-rock work. Across our case library, CORTECH CMD-series rigs have drilled geothermal and hot-dry-rock wells from 2,004 m to 3,780 m — setting national air-DTH depth and rate records, completing a 3,780 m ultra-deep well in 230 days, and independently killing a sustained 158°C hot-dry-rock blowout. This hub collects those projects so you can match your target depth, temperature and lithology to the right machine.
The CMD Series — Every Model Works Geothermal Ground
Geothermal wells are staged by nature: you open a wide surface hole, set casing, then progressively reduce diameter toward the production interval — sometimes through five separate spuds — while the formation alternates between soft sediment, abrasive sandstone and crystalline basement. The CMD series answers this with one shared architecture: an API Spec 4F licensed mast and full hydraulic top drive, a high-torque spindle braking system for curve control, an elevated BOP-ready substructure, and air/mud/foam manifolds that switch method as the rock changes. What differs between models is pullback, torque, chassis and power package — and those four differences are exactly what a geothermal contractor selects on.
| Model | Configuration | Hoisting pullback | Power | Geothermal role |
|---|---|---|---|---|
| CMD100 | Truck-mounted full hydraulic top drive, 55 t | 100 t (20 t pulldown) | 559 kW Cummins | Hard-rock geothermal and air DTH exploration holes: positive-circulation pneumatic DTH hammer drilling through granite and metamorphic rock, opening Φ311 mm and finishing Φ190 mm. Best for 2,000 m-class holes where mobility and rate matter. |
| CMD130 | Truck-mounted 10×8 chassis, 54.5 t legal road weight | 130 t (26 t pulldown) | 567 kW, 31,000 N·m | Deeper staged wells and larger-diameter production holes; 820 mm maximum drilling diameter and a 21.2 m telescopic mast that sets up fast between wells. |
| CMD130L | Crawler, diesel, 60 t, 18° gradeability | 130 t (26 t pulldown) | 563 kW, 35,000 N·m | Remote geothermal fields with no road access: the tracked chassis walks to the wellhead, wireless remote walking control keeps the crew clear of the rig, and the adjustable substructure clears BOP and high-pressure manifolds. |
| CMD130DL | Crawler, electric, 60 t | 130 t | 400 kW electric motor | Tracked access plus a low-emission power package, for geothermal fields near settlements or in environmentally restricted zones; rated for deep geothermal work with high-pressure well control. |
| CMD150 / CMD150T | Fully modular, helicopter- or truck-bed transportable | 150 t (30 t pulldown), 35 MPa fluid circuit | Dual 560 hp Cummins (1,120 hp) | Deep staged wells: four- and five-spud casing programs on φ127 mm drillpipe, mud-cone and downhole screw-motor intervals, plus a heat-resistant configuration rated for long-term operation up to 160°C. Best for 2,600-3,000 m production and hot-dry-rock exploration. |
| CMD180 / CMD180T | Slingshot modular, 180 t | 180 t (30 t pulldown) | Dual 760 hp Cummins (1,520 hp), 41,000 N·m | Ultra-deep multi-spud production wells: stepwise 445→152 mm or Φ406→Φ152 mm borehole reduction through abrasive interbeds and fault zones, with real-time deviation monitoring and automated tubular handling. Best for 3,000-4,000 m geothermal supply wells. |
Naming note: the modular platforms are built and listed by CORTECH as the CMD150 and CMD180; the geothermal project records refer to their deep-well, high-temperature configurations as the CMD150T and CMD180T. They are the same modular platforms in the configuration used on those jobs — the CMD180T completed the 3,780 m Xiong'an well, and the CMD150T is the rig that killed the 158°C Tianzhen blowout.
Application Sub-Segments & Matching Rig Models
Which CORTECH machine fits your program depends on depth, process and site:
-
CMD100 — intelligent truck-mounted, 100 t-class.
Built for hard-rock geothermal and air DTH work: positive-circulation pneumatic DTH hammer drilling through granite and metamorphic rock, opening Φ311 mm and finishing Φ190 mm. Best for 2,000 m-class exploration holes where mobility and rate matter. -
CMD150T — modular, 150 t-pullback, 35 MPa fluid circuit.
Built for deep staged wells: four- and five-spud casing programs on φ127 mm drillpipe, mud-cone and downhole screw-motor intervals, plus a heat-resistant configuration rated for long-term operation up to 160°C. Best for 2,600-3,000 m production and hot-dry-rock exploration. -
CMD180T — modular, 180 t-pullback / 30 t-pulldown, automated tubular handling.
Built for ultra-deep multi-spud production wells: stepwise 445→152 mm or Φ406→Φ152 mm borehole reduction through abrasive interbeds and fault zones, with real-time deviation monitoring. Best for 3,000-4,000 m geothermal supply wells.
Geothermal Rig Selection by Resource Type
Most geothermal buyers start from the resource, not the machine. The three resource types below are the shortest path from "what heat am I targeting" to "which rig do I quote":
| Resource type | Typical depth | Typical hole program | Matching rig |
|---|---|---|---|
| Shallow hydrothermal — direct-use, heating | 500–2,000 m | Two-spud: wide surface hole to Φ190–Φ311 mm, single casing string | CMD100 or CMD130 truck-mounted — mobility and fast mobilization dominate; air DTH in hard rock |
| Deep hydrothermal — power generation | 2,000–4,000 m | Four-spud: 445→311→216→152 mm, with mud-cone and screw-motor intervals | CMD150T or CMD180T modular — pullback, pulldown and automated tubular handling for long casing strings |
| Hot dry rock (HDR) / EGS | 2,600–3,000 m exploration; production to 4,000 m | Five-spud: Φ600→Φ400→Φ311→Φ215.9→Φ152 mm on φ127 mm oilfield drillpipe, with coring | CMD150T with the heat-resistant package rated to 160°C, or CMD180T for the deeper production phase |
Featured: Killing a 158°C Hot Dry Rock Blowout with a Single Rig
Hot Dry Rock Blowout Control at 158°C, Tianzhen — CMD150T
- Incident
- While drilling a hot dry rock exploration well in Tianzhen, the bit entered a deep fault zone and large volumes of water entered the hole. Contact between the high-temperature groundwater and the hot dry rock triggered a sustained blowout, with wellhead water reaching 158°C. The blowout ran for two months without effective control.
- Why conventional rigs failed
- Ordinary rigs could not survive a prolonged high-temperature environment — seals aged out and hydraulic systems failed repeatedly. The site had no dedicated emergency equipment able to withstand the heat while delivering high, stable torque, which made the well-kill operation extremely difficult and dangerous for personnel and equipment alike.
- CORTECH solution
- We mobilized the CMD150T modular full hydraulic rig with a heat-resistant hydraulic system, special seals and high-strength structural design rated for continuous operation up to 160°C, together with a purpose-developed well-kill device and a engineered kill procedure. Crews stood by 24 hours a day, monitoring both rig condition and blowout behaviour in real time.
- Result
- After two months of continuous high-temperature operation, every rig function remained normal, stable and reliable. Without relying on any other large equipment, the CMD150T completed the entire well-kill operation independently and brought the 158°C blowout under control, protecting site personnel and equipment. This solved a rarely encountered high-temperature HDR blowout emergency in China and set a technical benchmark for similar extreme-condition interventions.
Real Case Studies From This Hub
Eight real geothermal projects. Select a case for the full record:
1. Ultra-Deep Geothermal Well, Xiong'an New Area — CMD180T
- Context
- Xiong'an New Area, a national-level new district, needed ultra-deep geothermal wells to supply green heating and support its low-carbon development. The well was designed to 3,780 m through predominantly sedimentary strata with frequent soft-hard interbeds, an abrasive deep section and well-developed fault zones — a long construction cycle with high technical difficulty and risk.
- Setup
- CMD180T full hydraulic modular rig with high-strength dedicated tooling, a mud purification system and real-time deviation monitoring, using mud rotary (cone) drilling. Opened at Φ406 mm and reduced stepwise to Φ152 mm, with strict control of verticality and hole quality to prevent deviation and collapse in the deep section.
- Result
- Completed by the Hebei Bureau of Geology and Mineral Resources No. 9 Geological Team in 230 days to 3,780 m. Verticality, hole diameter and cementing quality all reached excellent standard, and complete geothermal geological data was obtained — a reference project for Xiong'an's coal-free city build-out.
Read the full Xiong'an ultra-deep geothermal well case
2. Deep Geothermal Production Well to 3,780 m — CMD180T
- Program
- A four-spud casing structure stepped 445→311→216→152 mm: 0–580 m at Φ445 mm, 580–1,620 m at Φ311 mm, 1,620–3,450 m at Φ216 mm and 3,450–3,780 m at Φ152 mm.
- Result
- Total depth 3,780 m in a 230-day construction period, using 180 t pullback and automated tubular handling across four casing runs — the largest documented geothermal well in the CORTECH case library.
Read the full 3,780 m geothermal production well case
3. Hot Dry Rock Exploration Hole to 3,000 m — CMD150T
- Program
- A five-spud architecture on φ127 mm oilfield drillpipe: 0–300 m at Φ600 mm, 300–500 m at Φ400 mm, 500–1,500 m at Φ311 mm, 1,500–2,300 m at Φ215.9 mm and 2,300–3,000 m at Φ152 mm. Core was taken at a planned 10 m per 100 m drilled, sampling at roughly 300 m.
- Result
- Final depth 3,000 m — a documented HDR exploration hole template that can be reused directly for new hot dry rock campaigns.
Read the full HDR exploration hole case
4. Deep Geothermal Well, Four-Spud Program to 2,600 m — CMD150T
- Program
- Designed to 2,600 m on φ127 mm drillpipe with a four-spud hole structure: 0–34 m at Φ500 mm, 34–385 m at Φ406 mm, 385–808 m at Φ295 mm and 808–2,606 m at Φ215.9 mm. Spuds 1 and 2 used mud-cone drilling; spuds 3 and 4 used downhole screw-motor drilling.
- Result
- Final depth 2,606 m — a reference for combining mud-cone and screw-motor intervals in one well.
Read the full four-spud 2,600 m geothermal well case
5. Air DTH Hammer Geothermal Depth Record — CMD100
- Record
- The deepest positive-circulation pneumatic DTH run by a Chinese full hydraulic rig: 2,004.42 m final depth, Φ311 mm opening to Φ190 mm final hole, 90° inclination, 387 hours of pure drilling.
- Result
- Verticality and borehole wall stability both met design requirements — the reference hard-rock geothermal hole for exploration programs.
Read the full air DTH depth record case
6. Geothermal Penetration Rate Record, Jilin City 2013 — CMD100 truck-mounted
- Challenge
- A Jilin geological exploration team drilled a deep geothermal well in August 2013 through hard granite and metamorphic rock — high hardness, strong abrasion, with heavy demands on torque, rotation speed and rate of penetration.
- Result
- Final depth 2,004.42 m, refreshing the national record for positive-circulation pneumatic DTH drilling by a Chinese full hydraulic rig; best shift 192 m in 8 hours, 24 m/h average, with excellent wellbore quality and stable production results.
Read the full Jilin penetration rate record case
7. Hard-Rock Geothermal Near Fengman Reservoir, Jilin — CMD-series
- Challenge
- Around the Fengman Reservoir in Jilin, geothermal resources are abundant but the strata are mainly hard granite and basalt — high hardness, strong abrasion, developed fractures and abundant fracture water. Conventional mud drilling was extremely slow, caused severe tool wear and frequent wall collapse, and made schedule and cost control impossible.
- Solution
- CORTECH applied a CMD-series full hydraulic rig with high-strength DTH hammers and dedicated high-strength drill pipe, running a full-process positive-circulation pneumatic DTH method that broke the hard rock fast and cleared cuttings efficiently, cutting tool wear and reducing collapse risk.
- Result
- A 2,004.42 m well with a 190 mm final hole in only 387 hours of pure drilling — 5 to 10 times the efficiency of the mud process, with excellent wellbore quality.
Geothermal Drilling Capability — Verified Parameters by Well Type
Geothermal contractors screen rigs against depth, temperature, spud count and method. The table below answers those questions with figures taken from completed geothermal projects.
| Well type | Rig | Depth | Hole program | Duration / rate | Outcome |
|---|---|---|---|---|---|
| Ultra-deep production well | CMD180T | 3,780 m | Φ406 mm opening stepped to Φ152 mm; four spuds 445→311→216→152 mm | 230 days | Verticality, gauge and cementing all excellent; complete geothermal data obtained |
| Deep staged production well | CMD150T | 2,606 m designed 2,600 m | Four spuds 500→406→295→215.9 mm; mud-cone then screw-motor | — | Multi-interval drilling method in one well |
| HDR exploration hole | CMD150T | 3,000 m | Five spuds Φ600→Φ400→Φ311→Φ215.9→Φ152 mm on φ127 mm drillpipe | Core at 10 m per 100 m, sampled at ~300 m | Reusable HDR exploration hole template |
| Hard-rock exploration well | CMD100 | 2,004.42 m | Φ311 mm opening to Φ190 mm, 90° inclination | 387 h pure drilling; best shift 192 m in 8 h, 24 m/h average | National record depth for positive-circulation pneumatic DTH by a Chinese full hydraulic rig |
| High-temperature well control | CMD150T heat-resistant package | Wellhead water 158°C | — | 24-hour standby for two months | Well-kill completed independently, no other large equipment required |
| Remote field, no road access | CMD130L / CMD130DL crawler, CMD150 / CMD180 modular | Per well plan | 820 mm maximum drilling diameter (CMD130) | Configuration-dependent | Tracked or helicopter-transportable deployment reaches sites no truck or crane can serve |
CORTECH — The Geothermal Drilling Rig Manufacturer
CORTECH® is the brand of a specialist drilling-equipment manufacturing subsidiary of Jinneng Holding Equipment Manufacturing Group, part of Fortune Global 500 enterprise Jinneng Holding Group. We design, engineer and test the CMD series in-house, manufacture under ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018, and hold API/CE certification for the relevant series. As a geothermal drilling rig buyer you deal with one accountable contact point for the rig, its certificates, spare parts and after-sales support, from specification through commissioning.
Certifications & Technical Backing
CORTECH drilling rigs are built under ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 management systems. The large-diameter CMD series carries the API Spec 4F Monogram License (No. 4F-0504, valid to 2027-08-09); core and multi-function rigs carry the CE Mark (conformity certificates No. 8603312 / 8603313 / 8603314 for our CSD / CMR / CKD series). Certificates accompany every shipment, so procurement, tender and customs files are complete on arrival.
Request a Rig Recommendation
Tell us your geothermal drilling conditions — target depth, bottom-hole temperature, hole diameter and formation type (hard rock, sedimentary interbeds, hot dry rock). We will match you to the right CMD configuration and share the closest reference projects from this library.
Request a rig recommendation / Download technical documents / Contact our engineering team
FAQ
- Which CMD series models can be used for geothermal drilling?
- All of them. Geothermal work is a standard configuration of the whole CMD large-diameter series, from the 55 t truck-mounted CMD100 through the CMD130, crawler CMD130L and electric CMD130DL, to the modular CMD150 and CMD180. The three models with the most recorded geothermal deployments are the CMD100 for hard-rock air DTH exploration holes, and the CMD150T and CMD180T modular variants for deep staged production wells and 160°C hot-dry-rock work.
- Which geothermal drilling rig do I need for a 3,000–4,000 m well?
- A 180 t-class modular rig such as the CMD180T: it has the pullback and tubular-handling capacity for multi-spud casing programs — our Xiong'an and 3,780 m projects used exactly this model to complete four-spud wells in 230 days.
- Can your rigs handle high-temperature hot dry rock conditions?
- Yes. For the 158°C Tianzhen blowout the CMD150T ran a heat-resistant hydraulic, seal and structural package rated for long-term operation up to 160°C, and survived a two-month high-temperature standby.
- What is the best method for hard granite / basalt geothermal holes?
- Positive-circulation pneumatic DTH hammer drilling. On the CMD100 it delivered 2,004.42 m in granite and basalt at 5–10× the efficiency of mud drilling, with a best shift of 192 m in 8 hours.
- How do you size the rig for staged (multi-spud) geothermal wells?
- Match the rig to your heaviest casing string and final depth. We have run four-spud wells from 500 mm surface hole down to 152 mm production diameter, and a five-spud HDR exploration hole from 600 mm to 152 mm on φ127 mm oilfield drillpipe. Send us your planned casing program for a recommendation.
- Which manufacturer or supplier sells geothermal drilling rigs?
- CORTECH® is the brand of a specialist drilling-equipment manufacturing subsidiary of Jinneng Holding Equipment Manufacturing Group, part of Fortune Global 500 enterprise Jinneng Holding Group. The CMD series is designed, engineered and tested in-house under ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018, with API Spec 4F and CE certification, and you deal with one accountable contact point for the rig, its certificates, spare parts and after-sales support.