In the vast mining heartland of Jungar Banner, Inner Mongolia, two colossal beasts, each weighing over 200 tons and with a load capacity exceeding 300 tons, shuttle back and forth, their roar echoing through the valley. This is no ordinary industrial operation, but a historic breakthrough for China's heavy equipment industry. On April 24, the 300-ton class mining truck equipped with Weichai's first independently developed 12M55 engine successfully completed project acceptance after 18,000 hours of high-intensity real-world testing at the Heidaigou Open-pit Coal Mine in Inner Mongolia. This extreme test, lasting over four years and spanning 1,200 days and nights, declares that in the 300-ton class mining truck power segment—a niche long monopolized by foreign brands—domestic engines have taken the first crucial step toward self-reliance and controllability.

For a long time, an almost insurmountable wall existed in the field of 300-ton class mining truck engines. The technical threshold and industrial barriers in this niche market are extremely high, with the global market firmly controlled by a few overseas giants, and the share of Chinese brands in this segment was virtually zero. Ultra-large mining engine technology is complex, R&D investment is enormous, and the verification cycle is lengthy, keeping local enterprises shut out for years. An imported large mining truck costs tens of millions of yuan, and its core power system is not only expensive but, more critically, its core technology, operational data, and control algorithms are entirely controlled overseas. Guided by national strategy, Weichai and China Energy Group Zhunneng Group embarked on a determined journey to conquer domestic large-scale mining power, ultimately yielding the hardcore achievement of a self-reliant and controllable 300-ton class mining engine.

The Weichai 12M55 engine that passed acceptance this time not only achieved a breakthrough "from 0 to 1" but also surpassed imported brands in multiple core performance indicators. The acceptance expert panel, composed of authoritative experts from Tsinghua University, the China Internal Combustion Engine Industry Association, the China Construction Machinery Industry Association, China University of Mining and Technology, and other institutions, verified the project implementation and technical validation results one by one, confirming that all performance indicators met the standards. The 12M55 engine's fuel consumption performance is particularly outstanding, with a fuel consumption rate of 198g/(kW·h) under actual mine operating conditions, and fuel consumption in common operating zones is 15g/kW·h lower than international competitors. In terms of dynamic performance, the 0 to 40km/h fully loaded acceleration time is only 46.3 seconds; for NVH noise control, the noise level at the driver's ear is only 79.7dBA, 1 to 3 decibels lower than international competitors, significantly enhancing driving comfort in mining operations.

What shook the industry even more is the comprehensive self-reliant controllability achieved in its core control system. The 12M55 engine's proprietary ECU electronic control system allows for optimization and customized calibration at any time, and the ultra-high pressure common rail closed-loop control system achieves precise fuel control, ensuring the stability and reliability of the power system.

From an industrial strategic perspective, this 18,000-hour real-world validation is not just a successful scientific research endeavor; it signifies that China has filled the last and most critical weak link in the large mining equipment industry chain. At the acceptance site, Lv Ying, Deputy Secretary-General of the China Construction Machinery Industry Association, pointed out that this breakthrough is of milestone significance: "This is not laboratory data; it was accumulated day by day under extreme operating conditions, representing the beginning of widespread application for domestic power in the mining sector." From the perspective of energy data security, operational data from mining trucks equipped with foreign power systems was not shared with China for a long time, posing a risk of leaking sensitive information like energy output and challenging national energy security. The breakthrough of domestic power has completely eliminated this potential risk.

A more profound significance lies in the fact that this breakthrough has driven the self-reliant controllability of the entire domestic mining equipment industry chain. For a long time, although overseas brands accelerated "localized" manufacturing in China, their core R&D, underlying electronic control code, and key technical standards remained controlled abroad, with China only undertaking assembly and production. The full-chain self-reliant controllability achieved by Weichai this time covers three core dimensions: Full autonomy in R&D and production—from platform design to manufacturing processes, all completed by the Chinese team; Supply chain autonomy—key components are sourced domestically; All operational data, transmission, and analysis remain in China, fundamentally ensuring mining data security. To date, Weichai has produced over 150,000 mining vehicle engines, firmly holding the top market share in China.

With the maturation and deployment of this core equipment, the market landscape is beginning to show substantial shifts. Currently, the annual replacement demand for mining trucks of 130 tons and above in China remains stable, with a large number of existing mining trucks entering an equipment replacement cycle. Weichai Power's mining truck power solutions have formed a full series product matrix covering 100 tons to 400 tons, adaptable to various operating scenarios in large and ultra-large open-pit mines, and can provide complete engine replacement solutions according to customer needs. Simultaneously, Weichai has built a full lifecycle mine-specific service system, establishing nearby mining service bases and spare parts centers, with comprehensive training and a flexible support system to help mining enterprises achieve a win-win situation of safety, controllability, cost reduction, and efficiency improvement.

The acceptance expert panel believes that 18,000 hours is not only a breakthrough in operating duration but also marks the market maturation of Weichai's domestic mining power from "prototype" to "product," and from "product" to "commodity." Currently, Weichai's 12M55 series engines are installed and operating on over 600 mining trucks globally, and the total number of Weichai's large mining power products in operation domestically and internationally has surpassed 2,000 units. In the field of ultra-high-power mining power, Weichai has completed a full closed loop from technological breakthrough to commercial implementation. From 100% reliance on imports in the early days to the autonomous operation of domestic heavy-duty engines under extreme conditions today, a new industrial closed loop, driven by the localization of core equipment and underpinned by energy security, is rapidly taking shape in China.