EP-SE418T3 Triple-Stage Track Drive Planetary Gearbox

O EP-SE418T3 is a triple-stage track drive planetary gearbox producing 270,000 N·m from a 3,000 rpm motor input across i=166–364. Its ratio range starts at i=166 — reflecting the reality that the machines this unit serves never need to travel faster than approximately 0.85 km/h at 3,000 rpm motor input. At 2,200 kg, installation requires a ≥5,000 kg rated crane.

Gear mesh efficiency in a planetary set is primarily governed by pitch-line velocity at the tooth contact. As pitch-line velocity increases, hydrodynamic friction in the elastohydrodynamic oil film (EHL film) at the gear contact increases non-linearly — and efficiency decreases. At 270,000 N·m, EP-SE418T3's gear pitch circle diameters are larger than in EP-SE417T3's 220,000 N·m final stage. At the same 3,000 rpm motor input, the larger final-stage gears rotate more slowly (lower angular speed), producing a lower pitch-line velocity at the tooth mesh. The reduced pitch-line velocity means reduced EHL film viscous shear losses, directly improving mesh efficiency above the level achievable in SE417T3's smaller, faster-rotating gears.

EP-SE418T3's ratio range begins at i=166, compared to i=123 for EP-SE417T3. A minimum ratio of i=166 means the three stages collectively reduce speed by 166-fold at minimum. This higher minimum ratio allows each of the three stages to be designed with a more uniform individual stage ratio — each stage reducing speed by approximately i^(1/3) = 5.5×, versus the uneven distribution needed when the minimum ratio is only i=123 (where one stage must provide a small reduction to reach the i=123 end of the range). More uniform stage ratios eliminate the efficiency penalty from having one stage operating far outside its optimal reduction ratio, contributing to the overall efficiency improvement.

Larger gear modules (tooth size) increase the contact ratio — the fraction of time two teeth are in simultaneous contact. Higher contact ratio distributes the transmitted load across more tooth pairs simultaneously, reducing the load per tooth and the associated sliding speed at the tooth root and tip where friction is highest. At 270,000 N·m, EP-SE418T3's final stage gear module is larger than in EP-SE417T3, producing a higher contact ratio and lower specific sliding velocity across the tooth profile. Combined with the lower pitch-line velocity from Mechanism 1, this produces measurably lower total mesh friction loss, returning the efficiency specification to the >94% level achievable at this scale.

EP-SE418T3 at 2,200 kg is the heaviest track drive unit in the Korea Ever-Power SE series covered on this site. The +750 kg increase over EP-SE417T3 (+52%) reflects four compounding engineering factors that scale non-linearly with torque at the 270,000 N·m level.

Very Large Walking Draglines — 5,000–7,000+ Tonne Class

The world's largest walking draglines — machines with bucket capacities of 100–170 cubic metres and operating weights exceeding 5,000 tonnes — include models with crawler-type propulsion systems that require EP-SE418T3 for the travel propel drives. These machines move infrequently (typically every few weeks between panel moves) but generate enormous tractive force requirements on mine bench surfaces. At 270,000 N·m per drive with i=200–280, EP-SE418T3 handles the required tractive force for these machines at their steepest operational gradients with adequate safety margin that EP-SE417T3 at 220,000 N·m cannot provide. The >94% efficiency is operationally significant at this scale: 1% efficiency improvement in a machine with multi-megawatt hydraulic propel power translates to tens of kilowatts less heat in each drive, reducing housing surface temperature and extending oil change intervals on machines with access-constrained maintenance. For a machine with 12 propel drives at full power, the difference between >93% and >94% efficiency per drive is roughly 10–15 kW less heat per drive — approximately 120–180 kW less total propel system heat — measurable as lower main pump outlet temperatures and longer filter change intervals in the hydraulic system.

TBM Main Drive Propel Rings — 22m+ Bore Diameter

TBMs in the very largest bore diameter class — 22–16 metre machines being used for the widest motorway tunnels, large waterway crossings, and major underground infrastructure projects — generate per-unit propel drive load requirements that may exceed EP-SE417T3's 220,000 N·m in very hard rock with high thrust requirements. EP-SE418T3 at i=180–230 provides the required thrust with adequate margin for very hard granite and quartzite geology where the per-unit thrust load at 270,000 N·m per unit is the design governing factor. The >94% efficiency is directly relevant for TBM propel drives, which operate at near-continuous duty for months at a time: lower heat generation per kilowatt reduces thermal management requirements in the confined tunnel propel ring environment.

Ultra-Heavy Rope Shovels — Very Largest Production Class

The very largest electric rope shovels — machines with dipper capacities exceeding 100 cubic metres and operating weights approaching 2,000 tonnes — may require EP-SE418T3 for the crawler propel drives when site conditions produce drive torque requirements that exceed EP-SE417T3's 220,000 N·m capacity with adequate safety margin. At very high-gradient mine bench access roads or on soft saturated ore floor, the tractive force demand at these machine weights can approach the EP-SE417T3 limit, and EP-SE418T3 provides the additional 22.7% torque capacity needed to maintain the required engineering safety factor. Korea Ever-Power calculates the specific drive torque requirement for any rope shovel specification same day.

Extreme-Scale Marine and Offshore Crawler Systems

The largest offshore and marine heavy crawler platforms — systems moving the heaviest offshore platform deck sections, large jacket structures, and specialised marine infrastructure components of 3,000–5,000+ tonne payload — require EP-SE418T3 when total system weight exceeds EP-SE417T3's service envelope. These systems operate in salt water immersion and highly corrosive marine atmospheres. EP-SE418T3's 60–80 litre oil volume provides a larger contamination buffer in salt water environments, and the dual-cone floating metal face seals sustain full immersion without oil contamination. Auxiliary winch and tensioner equipment on these platforms use worm gear reducers for self-locking cable drum hold, independent of the EP-SE418T3 travel drives.

Specialised Heavy Industrial and Defence Platforms

EP-SE418T3 also serves specialised tracked platforms above 3,000 tonnes in defence, heavy industrial transport, nuclear power plant construction, and major civil infrastructure projects where the combination of machine weight, site gradient, and required safety factor produces drive torque demands that require 270,000 N·m per unit. The >94% efficiency reduces thermal signature in sensitive environments, and the robust dual-cone face seal system sustains contaminated environments without maintenance-intensive seal replacement programmes.

Large-Scale Land Development and Major Infrastructure

Ultra-large tracked platforms for major dam construction, large coastal land reclamation projects, and major port infrastructure development at the extreme upper weight range require EP-SE418T3 when combined equipment weight and site resistance exceed the EP-SE417T3 service envelope. The downstream agricultural and land development gearboxes for the heavy earth-working implement drives operate on separate PTO circuits independent of the EP-SE418T3 travel drives.

Motor Selection, Ratio, Brake — Same Day

EP-SE418T3's 3,000 rpm maximum applies, and motor displacement must be sized for this limit. Korea Ever-Power's same-day engineering response covers: motor displacement for your hydraulic power at 3,000 rpm; ratio from i=166–364; 2,000 N·m brake adequacy including counterbalance valve requirements; and dimensional cross-reference against your incumbent drive. For EP-SE418T3 versus EP-SE417T3 boundary applications, Korea Ever-Power calculates both simultaneously and provides a comparison document — no charge, before any order commitment.

Pre-Assembled and Tested at 2,200 kg

Korea Ever-Power provides EP-SE418T3 pre-assembled with matched large-displacement motor (3,000 rpm maximum), overcenter valve, and pressure relief valve. The 2,000 N·m brake is function-verified before shipping. At 2,200 kg requiring a ≥5,000 kg crane at the installation site, a pre-assembled and brake-verified unit arriving as a complete tested assembly is not just convenient — it is the practical approach. The unit arrives ready for a single crane lift into the chassis bore and hydraulic line connection, eliminating all on-machine motor fitting and brake commissioning.

Stage-Level Parts — 2,200 kg Serviced

Korea Ever-Power stocks all EP-SE418T3 internal components by stage: Stage 1, 2, and 3 sun gear and planet set assemblies; 2,000 N·m brake disc pack (friction discs, separator plates, O-ring kit); dual-cone floating face seal kits; taper bearing sets per bearing position; housing O-ring kits. At 2,200 kg and 270,000 N·m, returning the unit to a factory for any component-level repair is practically impossible without a 100+ tonne crane relocation operation. Stage-level in-situ repair with Korea Ever-Power components is the only viable maintenance approach at this scale. For operators running multiple EP-SE418T3 units at the same site, Korea Ever-Power’s same-day oil sampling guidance and stage-specific wear signature interpretation service allows the maintenance team to identify which units require attention and what components to pre-position, well ahead of any failure event. This forward-looking maintenance approach is especially important at 2,200 kg per unit, where an unplanned failure with no components on hand means a multi-week crane and logistics operation under any circumstances.

12/18-Month Warranty

12 months from commissioning or 18 months from shipment, covering all three planetary stages, the 2,000 N·m brake assembly, and the floating face seals. Warranty parts dispatched from Korea Ever-Power stock — no requirement to return the 2,200 kg unit. For OEM fleet buyers stocking EP-SE418T3 before machine assembly, warranty begins at commissioning.

Stock and Framework Supply

Standard configurations from stock in 7–14 days. Pre-assembled packages: 30–45 days. At 2,200 kg and this torque class, an unplanned drive failure in a 5,000-tonne dragline or 22-metre TBM represents catastrophic project cost. Korea Ever-Power discusses reserved production capacity, consignment stock, and framework supply terms for the largest fleets at this scale. Contact Korea Ever-Power with fleet details and annual volume for emergency response planning and framework pricing.

−25°C to +90°C — 2,200 kg Thermal Mass

At 2,200 kg nodular iron, the thermal mass is approximately 1,100 kJ per degree — the highest in the SE series on this site. Despite the >94% efficiency recovery, any absolute heat generation at 270,000 N·m scale is substantial; the 2,200 kg housing absorbs it most slowly, providing the longest thermal run-up time and greatest resistance to temperature peaks. For high-ambient and high-duty-cycle operation, Korea Ever-Power provides thermal assessment on request at no charge. At 2,200 kg of nodular cast iron with a surface area proportional to the unit's physical scale, EP-SE418T3 also dissipates heat more effectively by natural convection than lighter SE units at the same housing temperature, reducing the effective thermal resistance to ambient relative to the heat generated per kilowatt of power transmitted. This contributes to maintaining housing surface temperature below the +90°C limit even in high-ambient environments with sustained maximum travel duty cycles, without additional cooling measures in most standard applications.

We supply propel drive systems for the world's largest walking draglines, including crawler-based machines in the 5,000–6,500 tonne operating weight class at major coal and copper mines. Korea Ever-Power confirmed EP-SE418T3 for our largest platform after calculating that the required drive torque per unit at 5,800 tonnes on our worst-case access ramp configuration exceeded EP-SE417T3's 220,000 N·m capacity with the safety factor our engineering specification mandates. At i=215 for our standard operational ratio, the spring brake provides 2,000 × 215 = 430,000 N·m per drive mechanical hold — verified at our 8° acceptance gradient slope test with full machine weight. We also confirmed the >94% efficiency specification: our hydraulic oil temperature monitoring showed a measurable reduction in main pump outlet temperature compared to the EP-SE417T3 installations on our lighter machines, consistent with the higher efficiency reducing heat input to the hydraulic system. At 1,200 hours across four units at our Pilbara iron ore operation, zero failures.

Our largest project involved a 22.5-metre bore diameter mixed-ground TBM for a major river crossing in Hubei Province. The propel ring contained 48 individual drive units. Our ground load model for the hardest limestone strata sections required 250,000 N·m per unit with a 1.1× service factor — 275,000 N·m per unit required, which exceeded EP-SE417T3's 220,000 N·m by a substantial margin. Korea Ever-Power confirmed EP-SE418T3 at i=185 for our advance rate requirement. The efficiency specification of >94% was critical for our ventilation design — 48 drives operating continuously in a 22.5-metre tunnel generate substantial heat, and even 1% lower efficiency would have required additional ventilation capacity in our tunnel design. At 1,400 hours of continuous tunnelling through 4.8 km of tunnel (including 1.2 km of hard limestone at maximum thrust), zero EP-SE418T3 failures across all 48 drives. Korea Ever-Power's 7-14 day stock availability was the deciding factor in our component supplier selection — our project schedule required guaranteed spare unit availability within a 2-week window throughout the tunnelling programme. We keep four complete EP-SE418T3 units on-site at the tunnel portal as operational reserves, which Korea Ever-Power replenishes from stock within 14 days each time we consume one. This just-in-time reserve system — enabled by Korea Ever-Power's consistent stock availability — allowed us to reduce our initial stock holding from eight to four units without increasing project risk, reducing our upfront capital commitment by approximately half while maintaining full operational resilience.

We operate tracked crawler platforms for moving very large pre-assembled topsides sections at our offshore fabrication yard near Campos. Our largest platform moves topsides up to 4,200 tonnes from the fabrication hall to the quayside for load-out. Korea Ever-Power specified EP-SE418T3 at i=248 for our 16 travel drives after confirming that our maximum site gradient combined with the heaviest topside load and a 1.25× dynamic factor produced a per-unit drive torque of 258,000 N·m — above EP-SE417T3's capacity. The 2,000 N·m brake at i=248 provides 2,000 × 248 = 496,000 N·m per drive hold, giving us 2.1× safety factor against the maximum tractive force at our steepest yard gradient. Operating in a salt-laden, high-humidity coastal environment with regular high-pressure wash-down, the dual-cone floating face seals have shown zero oil contamination from water ingress in 2,500 hours across our 16 drives over three years of yard operation. The >94% efficiency has contributed to our platform's hydraulic oil staying 4–6°C cooler than our previous European-supplied drives, measurably extending hydraulic component service life.

QEP-SE418T3 is rated at >94% efficiency, which is higher than SE413T3–SE417T3 at >93%. Is this correct?

Yes, this is correct and reflects real physics rather than a rounding or specification discrepancy. Three mechanisms explain the >94% efficiency at 270,000 N·m. First: at 2,200 kg, the gear pitch circle diameters are physically larger than in EP-SE417T3 (1,450 kg). At the same 3,000 rpm motor input, larger gears produce lower pitch-line velocity at the tooth contact, reducing hydrodynamic friction in the elastohydrodynamic oil film — the dominant source of gear mesh loss. Second: EP-SE418T3's minimum ratio i=166 (vs i=123 for SE417T3) allows more uniform three-stage ratio distribution, reducing the peak torque in the highest-load stage and its associated friction loss. Third: the larger gear module at 270,000 N·m produces a higher contact ratio (more tooth pairs sharing load simultaneously) and lower specific sliding velocity across the tooth profile, both of which reduce friction loss. The net result is that the efficiency specification at this torque class is measurably higher than at the SE413T3–SE417T3 range. Korea Ever-Power can provide detailed efficiency analysis for your specific ratio and operating point if required for your thermal or hydraulic circuit design. For TBM propel ring applications where many drives operate simultaneously in a confined underground environment, the difference between >93% and >94% efficiency across 40–48 drives at full thrust is several tens of kilowatts in total heat reduction — a meaningful contribution to the tunnel ventilation capacity requirement and the thermal management of the hydraulic system.

QEP-SE418T3 starts at i=166 minimum ratio. EP-SE417T3 starts at i=123. Why does the larger unit have a higher minimum ratio?

The minimum ratio determines the fastest achievable output speed. At i=166 with 3,000 rpm motor input, the output is approximately 18.1 rpm — approximately 0.85 km/h at a 800 mm sprocket radius. The 3,000–7,000+ tonne machines served by EP-SE418T3 do not need to travel faster than this under any operational scenario. Unlike EP-SE417T3, which serves machines ranging from 2,000 to 5,000+ tonnes (some of which may need faster repositioning using the i=123–165 band), EP-SE418T3's machine class is entirely slow-travel: the fastest useful travel speed for a 5,000-tonne dragline is already at or below the 0.85 km/h that i=166 provides. Starting the ratio range at i=166 means all three stages can be optimised for the i=166–364 operational band without reserving stage design capacity for a low-ratio band that the machine would never use. This optimisation contributes directly to the >94% efficiency specification by allowing each stage to operate at or near its optimal individual ratio throughout the operating range.

QWhat are the oil volume, first-change procedure, and condition monitoring requirements for 2,200 kg?

EP-SE418T3 contains approximately 60–80 litres of gear oil depending on ratio configuration and motor adapter — the highest oil volume in the SE series as presented here. The exact fill volume is on the Korea Ever-Power dimensional drawing for your configuration. First oil change at 150 operating hours: allow 35–40 minutes full drain time with the unit warm — at 60–80 litres, incomplete drain leaves significant particle-laden oil in the sump. Refill with fresh API GL-5 VG 150 (below +15°C) or VG 220 (above +15°C). Subsequent changes: every 1,000 hours or annually. ICP oil sampling at each 500-hour interval is strongly recommended at this scale. With 60–80 litres, sampling provides a large representative volume — elemental baseline established at the 150-hour first change is the reference for all subsequent comparisons. Korea Ever-Power provides reference elemental baseline ranges for EP-SE418T3 units as part of the startup documentation package, and can advise on sample interpretation to distinguish stage-specific from bearing wear particle signatures. At 60–80 litres of oil per unit and multiple units per machine, a centralised sampling and analysis programme with results tracked against Korea Ever-Power’s reference ranges provides the earliest possible warning of developing wear — well before any symptom is detectable in machine performance. This proactive approach, combined with Korea Ever-Power’s 7–14 day stock availability for critical components, minimises unplanned machine downtime for what are typically the most production-critical machines in any mining or heavy civil operation.

QIs EP-SE418T3 a direct replacement for Rexroth GFT or Bonfiglioli units in the 270,000 N·m class?

For triple-stage units in the 270,000 N·m torque class, Korea Ever-Power provides a full dimensional cross-reference before any order — spindle bore, drum OD, sprocket BCD, hydraulic port specifications, motor interface spigot, brake pilot port — against your specific legacy model number and ratio code. At 270,000 N·m, specialised configurations within the Rexroth GFT and Bonfiglioli 700C families are the reference benchmarks; the cross-reference confirms which EP-SE418T3 configuration matches exactly, and flags any dimension requiring a resolution path. Provide the full model number with all suffix codes for the most accurate same-day cross-reference. Rexroth and Bonfiglioli are trademarks of their respective owners, cited for dimensional reference only.