{"id":1190,"date":"2026-06-26T05:45:16","date_gmt":"2026-06-26T05:45:16","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?p=1190"},"modified":"2026-06-26T05:45:16","modified_gmt":"2026-06-26T05:45:16","slug":"wheel-drive-planetary-gearbox-for-mining-dump-trucks","status":"publish","type":"post","link":"https:\/\/planetary-gearboxes.com\/fi\/wheel-drive-planetary-gearbox-for-mining-dump-trucks\/","title":{"rendered":"Py\u00f6r\u00e4vetoinen planeettavaihteisto kaivoskuorma-autoille"},"content":{"rendered":"
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\"Wheel<\/p>\n
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Korea Ever-Power \u00b7 Application Engineering \u00b7 Mining Dump Trucks<\/p>\n

Py\u00f6r\u00e4vetoinen planeettavaihteisto kaivoskuorma-autoille<\/h1>\n

A 600-tonne loaded haul truck descends a 3-kilometre pit ramp at 10% grade \u2014 the wheel drive must dissipate 180 MJ of braking energy without fade while propelling the largest wheeled vehicle on earth at torques exceeding 200,000 Nm per wheel. This is the ultimate wheel drive application.<\/p>\n

Browse Wheel Drive Planetary Gearboxes \u2192<\/a><\/p>\n<\/div>\n<\/div>\n<\/section>\n

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The Largest Wheel Drives in the World \u2014 200,000+ Nm per Wheel<\/h2>\n

Mining dump trucks (rigid-body off-highway haul trucks) are the largest wheeled vehicles ever built. The smallest class hauls 40 to 60 tonnes of payload; the largest class hauls 360 to 400 tonnes \u2014 with a gross vehicle weight (GVW) exceeding 600 tonnes. The planeettavaihteisto<\/a> at each rear wheel must transmit the torque to propel this mass up a 10% haul-road grade at 15 to 30 km\/h \u2014 and then retard the same mass during the loaded descent at controlled speed.<\/p>\n

\n\n\n\n\n\n\n\n
Class<\/th>\nPayload (t)<\/th>\nGVW (t)<\/th>\nEngine (HP)<\/th>\nWheel Torque<\/th>\n<\/tr>\n<\/thead>\n
Small (40\u2013100 t)<\/td>\n40\u2013100<\/td>\n70\u2013170<\/td>\n700\u20131,500<\/td>\n30,000\u201380,000 Nm<\/td>\n<\/tr>\n
Medium (100\u2013200 t)<\/td>\n100\u2013200<\/td>\n170\u2013350<\/td>\n1,500\u20132,700<\/td>\n80,000\u2013150,000 Nm<\/td>\n<\/tr>\n
Ultra (250\u2013400 t)<\/td>\n250\u2013400<\/td>\n400\u2013630<\/td>\n2,700\u20134,000+<\/td>\n150,000\u2013250,000+ Nm<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

The drive system architecture splits into two categories: mechanical drive (diesel engine through torque converter, transmission, and planetary final drive at each wheel) and diesel-electric drive (diesel engine driving an alternator, which powers electric traction motors at each rear wheel, with planetary final reduction at each wheel). On mechanical-drive trucks (typically the 40 to 150-tonne class), the planetary gearbox is the final reduction stage between the transmission output and the wheel hub \u2014 providing 15:1 to 25:1 reduction. On diesel-electric trucks (typically the 150 to 400-tonne class), the planetary gearbox reduces the electric motor speed (1,000 to 3,000 rpm) to the wheel speed (20 to 80 rpm) \u2014 providing 20:1 to 40:1 reduction.<\/p>\n

The output torque per wheel on an ultra-class truck exceeds 200,000 Nm \u2014 the highest of any wheel drive in this entire series by a factor of 3 to 5 over the next largest application (the wheel dozer at 40,000 to 80,000 Nm). The gear module, bearing bore diameter, and housing wall thickness are proportionally larger \u2014 with output gears exceeding 500 mm pitch diameter and output bearings exceeding 300 mm bore. These components weigh 200 to 500 kg per wheel drive assembly \u2014 and the precision manufacturing requirements (tooth profile, bearing raceway finish, housing bore concentricity) are identical to the smaller drives, making the manufacturing challenge scale with the size while the tolerance remains constant.<\/p>\n

Mining trucks operate 5,000 to 7,000 hours per year \u2014 on par with sugar cane harvesters and underground LHDs for the highest utilisation in the Wheel Drive series. But unlike those machines (which are seasonal or limited by ore availability), the mining truck operates at maximum load on every cycle: loaded up the ramp, dumped, empty back down, reloaded. There is no light-duty period \u2014 every cycle is a maximum-torque, maximum-brake-energy event. This sustained peak-duty operation produces fatigue loading at 2 to 3 times the rate of machines that alternate between heavy and light duty \u2014 and the gearbox life must be calculated for the continuous peak case, not the average case.<\/p>\n

The economic context amplifies the reliability requirement. An ultra-class mining truck costs USD 5 to 10 million \u2014 and generates USD 200,000 to 500,000 per day in ore revenue at full productivity. A final-drive failure that immobilises the truck for 24 hours costs USD 200,000 to 500,000 in lost production \u2014 plus USD 50,000 to 150,000 for the gearbox replacement and crane service. At these stakes, the mining industry invests heavily in condition monitoring: vibration sensors, oil analysis, temperature logging, and predictive-maintenance algorithms that detect final-drive degradation 500 to 2,000 hours before failure \u2014 providing time to schedule the replacement during a planned maintenance window rather than suffering an unplanned breakdown in the pit.<\/p>\n<\/section>\n

\"Wheel<\/p>\n

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Haul-Road Grade Descent \u2014 The Braking Energy That Dwarfs Every Other Application<\/h2>\n
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The loaded haul from the pit floor to the dump point is the defining duty cycle. A loaded truck at 600 tonnes climbs a 3-kilometre ramp at 10% grade \u2014 gaining 300 metres of elevation and storing 1,765 MJ of potential energy. During the loaded descent (returning to the pit floor after dumping), this energy must be dissipated. On diesel-electric trucks, the electric traction motors function as generators during descent \u2014 converting the kinetic and potential energy to electrical energy, which is dissipated as heat through resistor grids (dynamic retarding). The planetary gearbox transmits this retarding torque from the wheels to the motor\/generator \u2014 at the same torque levels as during propulsion but in the opposite direction.<\/p>\n

On mechanical-drive trucks, the retarding energy is dissipated through the engine compression brake, the transmission retarder, and the wheel-mounted wet-disc brakes. The planeettavaihteisto<\/a> transmits the braking torque from the wheel to the transmission retarder \u2014 and the wet-disc brake (mounted within or adjacent to the planetary housing) provides the final backup retarding capacity. A 170-tonne truck descending a 3-km, 10% grade at 40 km\/h must dissipate approximately 500 MJ \u2014 sustained over 4.5 minutes. This is approximately 1.85 MW of continuous retarding power \u2014 per truck \u2014 flowing through the wheel drive in the reverse direction.<\/p>\n

The thermal management of this energy flow determines the wheel drive life. The oil temperature in the planetary housing during a loaded descent can reach 120 to 150 degrees C on mechanical-drive trucks \u2014 because the wet-disc brake dissipates a portion of the retarding energy directly into the oil bath that lubricates the planetary gears and bearings. Dedicated oil cooling circuits (oil-to-air or oil-to-water heat exchangers) are sized to maintain the peak oil temperature below 130 degrees C during the worst-case descent \u2014 a thermal design that is unique to mining truck final drives and is not found on any other wheel drive application in this series.<\/p>\n

The loaded-descent speed is controlled by the retarding system \u2014 not by the wheel drive brakes. On diesel-electric trucks, the electric retarding capacity is typically 2,000 to 3,500 kW \u2014 sufficient to control the descent speed without any mechanical braking. The wheel drive wet-disc brakes are reserved for final stopping and parking \u2014 and rarely operate during the descent. On mechanical-drive trucks, the transmission retarder and engine compression brake provide the primary retarding \u2014 with the wet-disc brakes contributing 20 to 40% of the total retarding force during steep or long descents. The wheel drive gearbox must transmit the retarding torque in both directions (propulsion and retarding) without backlash impact at the torque-reversal point \u2014 because the transition from propulsion to retarding occurs at the crest of the ramp on every cycle.<\/p>\n<\/div>\n

\"601L1A<\/div>\n<\/div>\n<\/section>\n
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Autonomous Haulage \u2014 The Final Drive Without a Driver<\/h2>\n

Autonomous haulage systems (AHS) are deployed at over 30 mine sites worldwide \u2014 with fleets of 20 to 100+ trucks operating without human drivers. The autonomous system controls the throttle, braking, and steering \u2014 and the wheel drive must respond to these commands with the same deterministic precision required for autonomous LHDs (WD-22): \u00b10.5% speed accuracy, \u00b13% torque response, and sub-0.3-second response time. Any deviation from the commanded speed or torque causes the autonomous system to initiate a safety slowdown or emergency stop \u2014 reducing fleet productivity and potentially blocking other autonomous trucks on the haul road.<\/p>\n

The condition monitoring on autonomous trucks is more comprehensive than on manned trucks: vibration sensors on the final-drive housing, oil temperature and pressure sensors, speed encoders on the output shaft, and acoustic sensors that detect gear-mesh and bearing noise changes. This sensor suite feeds data to the fleet management system \u2014 which uses predictive-maintenance algorithms to forecast the remaining final-drive life and schedule replacements during planned maintenance windows. A final-drive failure on an autonomous truck is more consequential than on a manned truck: the autonomous truck cannot be manually nursed to the workshop, and the breakdown blocks the haul-road lane until a recovery vehicle (another large expense) can reach and tow the disabled truck.<\/p>\n

The autonomous duty cycle is more consistent than the human-operated duty cycle \u2014 the autonomous system does not over-speed on descents, does not brake harshly at the dump point, and does not overload the truck beyond the rated payload. This consistency actually extends the final-drive life by 10 to 20% compared to human-operated trucks on the same haul profile \u2014 because the autonomous system avoids the peak-load events that human operators occasionally produce through aggressive driving. The net effect is that autonomous mining represents both the highest absolute duty (continuous 24\/7 operation) and the most controlled duty (no operator variability) \u2014 a combination that favours high-quality, precisely specified final drives that can take full advantage of the reduced peak-loading to maximise the consistent-duty service life.<\/p>\n<\/section>\n

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Three Failure Modes Specific to Mining Dump Truck Final Drives<\/h2>\n
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1<\/div>\n
Oil thermal degradation from sustained retarding-energy dissipation during loaded descents<\/div>\n<\/div>\n

During a 4.5-minute loaded descent, the oil temperature can spike to 120 to 150 degrees C \u2014 and if the truck immediately begins the next loaded climb (without a cooling period at the pit floor), the baseline temperature for the next descent is elevated. On a 12-hour shift with 8 to 12 load-haul cycles, the cumulative thermal exposure can degrade mineral oil to the point of measurable viscosity loss within 500 to 800 hours. Synthetic PAO oil extends this to 2,000 to 3,000 hours \u2014 aligning the oil-change interval with the scheduled maintenance windows that mining fleets operate on 250 to 500-hour cycles. A single missed oil change after a high-thermal shift sequence can consume 20 to 30% of the remaining gear and bearing service life.<\/p>\n

Prevention: Synthetic PAO oil (mandatory). Dedicated oil cooler circuit sized for worst-case descent thermal load. Oil temperature monitoring with data logging. Oil analysis at every 250-hour service.<\/div>\n<\/div>\n
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2<\/div>\n
Gear tooth surface fatigue from sustained maximum-torque loaded climbing<\/div>\n<\/div>\n

During the loaded climb (600 tonnes up a 10% grade at 20 km\/h), the wheel drive operates at 80 to 100% of its rated torque for 6 to 10 minutes continuously. This sustained maximum-torque duty produces gear-tooth surface fatigue (micro-pitting and pitting) at rates that are 5 to 10 times higher than the intermittent peak-torque events on surface loaders and dozers. Over 5,000 hours per year (at 3 to 5 loaded climbs per shift, 2 to 3 shifts per day), the cumulative surface fatigue can initiate pitting on the output-stage sun and planet gears within 8,000 to 12,000 hours \u2014 even on case-hardened gears with DIN Class 6 tooth quality. The pitting progression from initiation to functional failure (tooth breakage) is typically 3,000 to 5,000 additional hours \u2014 providing a window for detection through oil analysis (increasing iron particle count) before catastrophic failure.<\/p>\n

Prevention: Case-carburised gears with minimum 58 HRC surface hardness. Super-finishing (isotropic superfinish) of gear tooth surfaces to Ra less than 0.2 microns. Oil analysis at 250-hour intervals for iron particle trend. Proactive gear replacement at the pitting-detection threshold.<\/div>\n<\/div>\n
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3<\/div>\n
Haul-road impact damage from potholes and washboard at loaded speed<\/div>\n<\/div>\n

Mining haul roads develop potholes, washboard corrugation, and edge deterioration from the repeated passage of 600-tonne loaded trucks. Each pothole impact at 30 to 40 km\/h produces a 5 to 15 g shock at the wheel drive output bearing \u2014 and at 600 tonnes GVW, the absolute bearing impact force reaches 300 to 900 kN per event. These impacts are the primary cause of bearing spalling on mining truck final drives \u2014 and the road-maintenance quality directly determines the final-drive bearing life. Studies from major mining operations show that final-drive bearing life varies by 30 to 50% between well-maintained haul roads (weekly grading) and poorly maintained haul roads (monthly grading) \u2014 making haul-road maintenance the most cost-effective final-drive life-extension strategy available.<\/p>\n

Prevention: Weekly haul-road grading. Speed limits on deteriorated road sections. Impact-rated output bearings (vacuum-degassed, inclusion-free steel). Tyre pressure management for optimal impact absorption.<\/div>\n<\/div>\n<\/div>\n<\/section>\n
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Usein kysytyt kysymykset<\/h2>\n
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How does a mining truck final drive differ from other wheel drives?<\/h3>\n

Three extremes: (1) torque \u2014 150,000 to 250,000+ Nm per wheel, 3 to 5 times higher than any other application; (2) sustained retarding energy \u2014 500 to 1,800 MJ per loaded descent, requiring dedicated oil cooling circuits that no other wheel drive needs; and (3) impact loading \u2014 300 to 900 kN per pothole impact at 600 tonnes GVW, the highest absolute impact force in the series. The mining truck final drive is the reference standard for extreme wheel drive engineering.<\/p>\n<\/div>\n

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What is the typical service life?<\/h3>\n

8,000 to 15,000 hours for the planetary gearbox \u2014 equivalent to 1.5 to 3 years at 5,000 hours per year. Gears: 10,000 to 15,000 hours (surface-fatigue limited on the output stage). Bearings: 8,000 to 12,000 hours (impact-fatigue limited, highly dependent on haul-road condition). Oil: 250 to 500-hour change interval with synthetic PAO. The cost of a single final-drive failure on an ultra-class truck (USD 50,000 to 150,000 for the gearbox plus USD 20,000 to 50,000 in truck downtime at USD 5,000 to 10,000 per hour of lost production) makes proactive component management essential. The mining industry uses total-cost-of-ownership (TCO) analysis for final-drive specification: a gearbox that costs 20% more upfront but lasts 40% longer reduces the per-tonne ore-haulage cost by 15 to 25% over the truck life \u2014 a saving of USD 500,000 to 2,000,000 per truck over a 10 to 15-year operational life.<\/p>\n<\/div>\n

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What gear ratio is typical?<\/h3>\n

15:1 to 25:1 for mechanical-drive trucks (combined with a 6 to 7-speed transmission). 20:1 to 40:1 for diesel-electric trucks (the planetary is the only reduction stage between the electric motor and the wheel). The ratio is optimised for the rimpull curve \u2014 providing maximum torque at the 15 to 20 km\/h loaded-climb speed and sufficient speed range for the 40 to 65 km\/h empty-return trip.<\/p>\n<\/div>\n

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Does Korea Ever-Power supply final drives for mining dump trucks?<\/h3>\n

Yes. Korea Ever-Power manufactures wheel drive planetary gearboxes for mining dump trucks from 30,000 to 250,000+ Nm with case-carburised super-finished gears, vacuum-degassed impact-rated bearings, integrated wet-disc brake provisions, dedicated oil-cooler circuit connections, and synthetic-oil-compatible materials. Provide the truck manufacturer, model, payload class, haul-road gradient, and drive system type (mechanical or diesel-electric) for a final-drive specification matched to the mine haul profile.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Mining Dump Truck Final Drives \u2014 The Ultimate Wheel Drive<\/div>\n

Korea Ever-Power provides mining truck final drives from 30,000 to 250,000+ Nm \u2014 the highest-torque, highest-energy, highest-impact wheel drives in the world.<\/p>\n<\/div>\n

View Wheel Drive Range \u2192<\/a><\/p>\n
sales@planetary-gearboxes.com<\/div>\n<\/div>\n<\/div>\n<\/section>\n

Toimittaja: Cxm<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"

Korea Ever-Power \u00b7 Application Engineering \u00b7 Mining Dump Trucks Wheel Drive Planetary Gearbox for Mining Dump Trucks A 600-tonne loaded haul truck descends a 3-kilometre pit ramp at 10% grade \u2014 the wheel drive must dissipate 180 MJ of braking energy without fade while propelling the largest wheeled vehicle on earth at torques exceeding 200,000 […]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[965],"tags":[],"class_list":["post-1190","post","type-post","status-publish","format-standard","hentry","category-application-and-technical-guid"],"_links":{"self":[{"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/posts\/1190","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/comments?post=1190"}],"version-history":[{"count":2,"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/posts\/1190\/revisions"}],"predecessor-version":[{"id":1195,"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/posts\/1190\/revisions\/1195"}],"wp:attachment":[{"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/media?parent=1190"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/categories?post=1190"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/fi\/wp-json\/wp\/v2\/tags?post=1190"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}