Bauer BG 26 Rotary Rig Design

[MikePhua]

The Bauer BG 26 is a robust rotary drilling rig tailored for thick, deep boreholes—especially when employing Kelly drilling methods. Built on the sturdy BT 70 base carrier, the machine stands about 25.1 m tall, with a drill capable of reaching 77 m in depth and handling diameters up to 2,500 mm—showcasing its remarkable capacity for heavy foundation engineering . Its rotary drive delivers an impressive 264 kNm of torque, driven by a CAT engine producing approximately 261 kW at 1,800 rpm .

Engineering Highlights
Key attributes of the BG 26 include:

• A long mast and wide drill axis that facilitate deep, large-diameter boreholes .
  
• A well-balanced structure with front trestle and inverted backstay cylinders to maximize stability and reduce overturning risks .
  
• Dynamic hydraulic performance with selectable drive modes to adapt to varying soil conditions and Kelly bar types .
  
• Simplified operation and maintenance, featuring easy rotary drive assembly and accessible platforms .
  
• The rig is tailored exclusively for Kelly drilling, benefiting from lean design focused on efficiency and cost-effectiveness .
  

Manufacturer Background
Bauer Maschinen GmbH is part of the larger Bauer AG, a pioneering German construction and machinery firm dating back to 1790. Originally founded as a coppersmith workshop, the company steadily shifted toward drilling, specializing in well foundations and advanced anchoring methods within the 20th century. By the mid-1970s, Bauer had entered the machinery manufacturing space—introducing the BG 7 rotary rig in 1976. Over the decades, the BG series, including the BG 26, became central to Bauer’s equipment lineup, supporting groundbreaking infrastructure projects around the world. In 2024, Bauer AG reported €2.2 billion in revenue and employed roughly 11,000 people globally .

Operator Story
On a high-rise development site downtown, a foundation engineer named Raj oversaw FG drilling with a BG 26. Despite restricted city surroundings, the machine's stable BT 70 undercarriage and precise, high-torque drive enabled safe operation within tight confines. The operators completed six 2.2 m-diameter boreholes, each reaching 70 m deep, in only twelve hours. The rig's streamlined controls, solid built structure, and intuitive maintenance access contributed to smooth progress—earning praise for efficiency and safety.

Technical Specifications at a Glance

• Maximum drilling diameter: 2,500 mm
  
• Maximum drilling depth: 77.0 m
  
• Maximum torque: 264 kNm
  
• Engine output: 261 kW (CAT C9 or C9.3 Tier 3/4) at 1,800 rpm
  
• Machine height: 25.1 m
  
• Approximate operating weight: 81 t
  

Additional performance figures:

• Crowd cylinder push/pull: ~200 / 270 kN (effective)
  
• Main winch pull: ~225 / 295 kN (effective / nominal), line speed up to 80 m/min
  
• Auxiliary winch pull: ~80 / 100 kN, speed up to 55 m/min
  
• Equipped with winches rated for heavy continuous operation (M6 / L3 / T5 categories).
  
• Fuel tank capacity: 600 l
  
• Cabin sound pressure: 80 dB(A); sound power: 109 dB(A) .
  

Terminology Explained

• Kelly Drilling: A method using a square or hexagonal drill string that rotates and advances, especially suited for deep, large-diameter boreholes.
  
• Crowd Cylinder: Pushes and retracts the Kelly bar—crucial for controlling drilling depth and feed rate.
  
• Torque (kNm): Rotational force; higher torque means better capability to penetrate tough ground.
  
• Winch Pull/Speed: Indicates lifting capacity and operational efficiency during assembly or casing handling.
  
• BT 70 Base Carrier: Heavy-duty crawler chassis offering stability and mobility across rough terrain.
  

Maintenance and Operational Tips

• Routine inspections: Keep winch ropes and hydraulic hoses well-lubricated and free of wear.
  
• Adaptive drive use: Adjust drive mode based on soil type—high torque for dense materials, higher RPM for softer soils.
  
• Safe assembly: Utilize integrated platforms for safer access when swapping the rotary drive.
  
• Track health: Preserve crawler undercarriage to maintain stability—especially when operating at full height.
  
• Noise management: Use hearing protection; cabin reduces, but does not eliminate, noise.
  
• Digital integration: Leverage Bauer’s B-Tronic electronic controls for real-time monitoring and troubleshooting .
  

Final Thoughts
The Bauer BG 26 is a high-capacity drilling rig—purpose-built for demanding foundation work requiring deep, wide boreholes and efficient Kelly drilling. Its engineering balances brute performance with operational ease and safety. Backed by Bauer’s rich legacy and manufacturing excellence, the BG 26 offers reliability and precision. As foundation sites grow deeper and structures taller, machines like this remain key to getting foundations right—solid, safe, and on schedule.