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Italian Minetek reduced the noise output of this sites Caterpillar Haul Trucks & Loader
The Caterpillar 789C and 789D Haul Trucks are robust, high-capacity vehicles designed for heavy-duty mining operations. With payload capacities of up to 213 metric tons, these trucks are engineered for efficiency and durability in demanding environments. The Caterpillar 994K Loader, a large-scale wheel loader, offers a bucket capacity of up to 25 yd³ (19.1 m³) and an operating weight of approximately 534,000 lb (242,000 kg). Equipped with advanced hydraulic systems and real-time diagnostic capabilities, these machines ensure optimal performance in open-cut mining operations. Their cabs provide operator comfort with noise and dust suppression, while their robust engines deliver the power needed for large-scale material handling.
Operating in close proximity to a noise-sensitive community, this copper mine required a solution to mitigate noise emissions from its Caterpillar 789C, 789D Haul Trucks, and 994K Loaders without compromising operational performance. Equipped with Minetek’s M-STEALTH™ Sound Attenuation Package, these large mining machines significantly reduced their noise output levels, enabling compliant operation and maintaining sound levels below regulatory thresholds.
Mine type – Open-cut
Mineral – Copper
Location – Coquimbo Region, Central Chile
Product/Scope – Turn-key M-STEALTH™ Package on the Caterpillar 789C, 789D Haul Trucks, and 994K Loader
Brief
The client required a comprehensive sound attenuation solution to meet stringent environmental noise regulations for their fleet of Caterpillar 789C, 789D Haul Trucks, and 994K Loaders. The primary objective was to reduce cumulative sound power generated by surface operations while maintaining productivity and machine efficiency, ensuring compliance with government regulations, and demonstrating social responsibility toward the nearby community.
Challenge
Located near a noise-sensitive township, the mine was subject to strict environmental regulations to prevent exceeding acceptable noise thresholds. Without an effective noise control solution, the operation risked operational restrictions and strained community relations. The challenge was to achieve significant noise reduction across the fleet while preserving payload efficiency and adhering to OEM specifications for backpressure and airflow.
Scope
Minetek Sound was engaged to deliver a tailored sound attenuation solution for the following machines:
- Caterpillar 789C Haul Trucks
- Caterpillar 789D Haul Trucks
- Caterpillar 994K Loaders
The solution needed to:
- Achieve site-specific sound power reduction targets.
- Minimize componentry to maintain payload efficiency.
- Adhere to strict OEM backpressure and airflow tolerances.
- Address site-specific noise characteristics to ensure optimal reduction levels.
Minetek engineers developed a comprehensive M-STEALTH™ Sound Package, customized to the acoustic profiles and operational demands of each machine class, ensuring compliance with regulatory requirements.
Results
Minetek’s M-STEALTH™ Sound Attenuation Package delivered significant noise reductions across the fleet:
Caterpillar 789C Haul Truck
- Before: 122 dB(A)
- After: 114 dB(A)
- Reduction: 8 dB(A)
- This reduction enabled the machine to operate 600 meters closer to the site boundary and noise-sensitive receptors
Caterpillar 789D Haul Truck
- Before: 122 dB(A)
- After: 114 dB(A)
- Reduction: 8 dB(A)
- This reduction enabled the machine to operate 600 meters closer to the site boundary and noise-sensitive receptors
Caterpillar 994K Loader
- Before: 120 dB(A)
- After: 116 dB(A)
- Reduction: 4 dB(A)
- This reduction enabled the machine to operate 400 meters closer to the site boundary and noise-sensitive receptors
These substantial accumulated noise reductions enabled the site to achieve compliance with environmental regulations, enhancing operational flexibility and supporting positive community relations. The installation was completed without safety concerns, and the solution maintained the machines’ productivity and performance.
Context
Site-specific noise characteristics were thoroughly investigated and integrated into the design of Minetek’s M-STEALTH™ Sound Attenuation Package to maximize noise reduction. The solution ensured compliance with stringent regulatory requirements while preserving the operational efficiency of the Caterpillar fleet. By enabling the machines to operate closer to the site boundary, the project enhanced the mine’s operational flexibility and supported its commitment to social responsibility.
Pre attenuation
122 dBA
The Caterpillar 789C and 789D Haul Trucks registered a factory sound frequency level of 122 dBA prior to Minetek Sound Attenuation.
Post attenuation
114 dBA
The sound output of the Caterpillar 789C and 789D Haul Trucks was tested after installing Minetek’s turn-key M-STEALTH™ sound attention solution. This registered a sound frequency level of 114 dBA.
Sound reduction
8 dBA
Minetek was able to reduce the sound output on the Caterpillar 789C and 789D Haul Trucks by 8 dBA.