DT660 and the Rise of Chinese Heavy Graders

[MikePhua]

The Emergence of Dingsheng Tiangong in Global Road Machinery
Dingsheng Tiangong, a Chinese manufacturer based in Jiangsu Province, has been producing road construction equipment since the 1960s. Originally focused on smaller graders and rollers for domestic infrastructure, the company expanded aggressively in the 2000s as China’s Belt and Road Initiative drove demand for large-scale earthmoving machinery across Asia, Africa, and Eastern Europe.
The DT660 grader represents one of the boldest entries from Tiangong into the high-horsepower motor grader segment. Designed to rival Caterpillar’s 24H and 24M series, the DT660 was engineered for mining haul road maintenance, large-scale highway grading, and airfield construction. Though exact production figures are not publicly available, Tiangong claimed the DT660 was the largest grader ever built in China at the time of its release.
Technical Overview and Design Features
The DT660 is a six-wheel-drive motor grader with a massive frame and extended moldboard reach. It features:

• Engine power exceeding 500 hp, typically sourced from a Weichai or Cummins diesel platform
  
• Operating weight over 60,000 lbs, placing it in the ultra-heavy grader category
  
• Blade length of approximately 16 feet, with hydraulic side-shift and pitch control
  
• Articulated frame for improved maneuverability on uneven terrain
  
• Dual-axle drive system with planetary reduction hubs for high torque output
  

Terminology clarification:

• Moldboard: The curved blade used to cut, spread, and level material.
  
• Articulated Frame: A jointed chassis allowing the front and rear halves of the machine to pivot independently, improving turning radius and control.
  
• Planetary Reduction Hub: A gear system that multiplies torque at the wheel, allowing heavy machines to move efficiently under load.
  

Comparisons to Western Counterparts
The DT660 drew immediate comparisons to Caterpillar’s 24H, a grader long used in mining operations across North America and Australia. While the DT660 mimics the general layout and size of the 24H, several differences stand out:

• The DT660’s articulation point is located farther forward, which some operators argue reduces cab stability during tight turns.
  
• Weld quality and casting thickness on early DT660 units were reportedly lighter than expected for machines of this size.
  
• Electrical systems and hydraulic routing appeared less refined than Western counterparts, with exposed lines and minimal shielding.
  

Despite these concerns, the DT660 offered a compelling value proposition. In markets where Caterpillar or Volvo machines were prohibitively expensive, Tiangong’s grader provided similar functionality at a fraction of the cost. This made it attractive to contractors in Central Asia, Sub-Saharan Africa, and parts of South America.
Field Performance and Operator Feedback
Operators who tested the DT660 in desert and mining environments noted several strengths:

• Excellent traction on loose aggregate due to its six-wheel-drive configuration
  
• Strong blade downforce, allowing deep cuts in compacted material
  
• Surprisingly quiet cab with air conditioning and ergonomic controls
  

However, concerns were raised about:

• Limited parts availability outside China
  
• Shorter service life of hydraulic seals and electrical connectors
  
• Articulation pin wear under heavy side loads
  

In one case, a DT660 was deployed in a copper mine in Inner Mongolia to maintain haul roads. The machine performed well for the first 1,000 hours but required a full articulation joint rebuild after 1,200 hours due to excessive play. The local dealer provided parts within two weeks, but downtime impacted production schedules.
Design Evolution and Export Strategy
Tiangong responded to early feedback by reinforcing the articulation joint and upgrading hydraulic hose quality. Later models of the DT660 featured improved cab insulation, better blade control electronics, and optional GPS grading systems. These upgrades were aimed at increasing export viability and competing directly with Komatsu and John Deere in emerging markets.
The company also began offering training programs for international operators and technicians, recognizing that machine longevity depends heavily on proper use and maintenance. In 2018, Tiangong signed distribution agreements in Kazakhstan and Nigeria, signaling a broader push into global infrastructure projects.
Recommendations for Prospective Buyers
For contractors considering the DT660:

• Ensure access to a reliable parts supplier or establish a direct relationship with Tiangong
  
• Budget for early component replacements, especially in high-duty cycles
  
• Train operators thoroughly on articulation limits and blade control systems
  
• Consider importing a second unit for parts cannibalization if operating in remote regions
  

While the DT660 may not match the build precision of Western graders, its raw power and affordability make it a viable choice for large-scale earthmoving where budget constraints outweigh brand loyalty.
Conclusion
The DT660 grader from Dingsheng Tiangong marks a significant milestone in China’s ascent in the heavy equipment industry. Though not without its flaws, the machine demonstrates that Chinese manufacturers are capable of producing high-horsepower graders suitable for demanding applications. As global infrastructure needs continue to grow, machines like the DT660 will likely play an increasing role in shaping roads, mines, and airfields far beyond China’s borders.