EP-SE419T3 Triple-Stage Track Drive Planetary Gearbox

The EP-SE419T3 is a triple-stage track drive planetary gearbox delivering 330,000 N·m at up to 2,500 rpm motor input. Its ratio range i=161–306 combines a slightly wider accessible maximum travel speed (i=161 gives ~15.5 rpm) with a 3,000 N·m spring brake that amplifies to 918,000 N·m at maximum ratio — a brake hold capacity that exceeds the full rated torque of every preceding SE unit on this site. At 2,850 kg, it requires a ≥8,000 kg certified crane for installation.

At r=850 mm sprocket radius and 15° gradient, two EP-SE419T3 drives at i=306 provide combined spring brake hold of 1,836,000 N·m. The rolling force on a machine at 15° is W × 9.81 × sin15° × r / drives. To calculate what machine weight this holds: W = 1,836,000 ÷ (9.81 × sin15° × 0.85) ÷ 1,000 = approximately 851 tonnes. A 4,000-tonne dragline on a 5° grade produces a rolling force of approximately 4,000,000 × 9.81 × sin5° × 0.85 / 2 = 1,456,000 N·m combined — within the spring brake hold. At steeper gradients for 4,000+ tonne machines, supplementary counterbalance valves are specified alongside the spring brake, with Korea Ever-Power providing the combined adequacy calculation same day. EP-SE418T3's maximum hold was 728,000 N·m per drive (or 1,456,000 N·m combined): EP-SE419T3 at 918,000 N·m per drive (1,836,000 N·m combined) provides 26% more spring brake margin at the same gradient, directly reducing the supplementary valve specification requirement.

The spring brake torque must satisfy two independent requirements: first, it must provide adequate hold on the steepest operational gradient at the maximum machine weight; second, the brake disc and friction plate material must not exceed safe thermal load during emergency braking from maximum travel speed. At 330,000 N·m rated drive torque and the machine weights served by EP-SE419T3 (4,000–10,000+ tonnes), increasing the spring brake from 2,000 N·m (as in EP-SE418T3) to 3,000 N·m was required to satisfy both criteria simultaneously. The 3,000 N·m brake uses a larger diameter multi-disc stack than EP-SE418T3's 2,000 N·m brake, providing greater thermal mass during emergency braking and wider contact area for sustained static hold. At 2,500 rpm maximum input (versus 3,000 rpm for SE418T3), emergency braking from maximum motor speed is also slightly less aggressive in energy terms, contributing to brake disc longevity in the 2,850 kg unit.

Across the sixteen SE models presented on this site, the spring brake torque has followed the machine class requirements: SE400T1 at 130 N·m, SE401T1 at 270 N·m, SE403T2 at 270 N·m, SE405.4T at 280 N·m, SE406AT at 430 N·m, SE406BT3 and SE407T3 at 530 N·m, SE413T3 at 610 N·m, SE414T3 and SE415T3 at 1,200 N·m, SE417T3 and SE418T3 at 2,000 N·m, and EP-SE419T3 at 3,000 N·m. Each step in brake capacity corresponded to a step in the machine weight class requiring adequate parking hold. EP-SE419T3's 3,000 N·m is not simply the next increment — it represents the first time the brake torque has exceeded 2,000 N·m in the SE series, a threshold that reflects the 4,000+ tonne machine class this unit is designed for, where parking on any gradient without supplementary valve assistance becomes achievable at the most commonly used operational ratios.

EP-SE419T3's 2,500 rpm maximum input speed is the lowest in the full SE series on this site. SE415T3 and SE417T3–SE418T3 are limited to 3,000 rpm. SE400T1 through SE414T3 allow 3,000–3,500 rpm. EP-SE419T3 adds another 17% reduction below the 3,000 rpm of its predecessor. Understanding why this happens — and what it means for motor selection and ratio range — is essential for engineers integrating this unit.

Extreme-Scale Walking Draglines — 7,000–10,000 Tonne Class

The very largest bucket wheel excavators and walking draglines ever built — machines with operating weights above 7,000 tonnes — include models with crawler-based travel systems where EP-SE419T3 provides the propel drive. At 330,000 N·m per drive, the tractive force available from two EP-SE419T3 drives at typical sprocket radii satisfies the most demanding mine bench tramming requirements even at machine weights above 7,000 tonnes with full dynamic shock factors. The 3,000 N·m spring brake at i=250–306 provides a combined hold of 1,500,000–1,836,000 N·m from two drives, covering emergency position hold on bench gradients of 5–8° even at very high machine weights without supplementary valve assistance.

Very Large TBM Propel Rings — 24m+ Bore Diameter

TBMs at the extreme upper end of bore diameter — 24+ metre machines planned or built for major waterway crossings, large combined tunnel systems, and major underground infrastructure — generate thrust requirements per propel unit that exceed what EP-SE418T3 (270,000 N·m) can provide in the hardest rock with the highest required safety factor per unit. EP-SE419T3 at i=180–220 provides 330,000 N·m per propel unit with adequate margin at 2,500 rpm motor input, which is already within the operating range of the large-displacement axial piston motors used at this TBM scale. The 3,000 N·m brake provides substantial position hold per unit, contributing to the combined propel ring emergency hold system in case of hydraulic pressure loss during excavation.

Largest Mining Rope Shovels — Very Highest Production Class

Electric rope shovels at the absolute top of the production class — machines with dipper payloads above 120 cubic metres and operating weights approaching 2,500 tonnes — produce propel drive torque requirements that may reach the EP-SE418T3 boundary at worst-case gradients and with required safety factors, requiring EP-SE419T3 for adequate margin. At 330,000 N·m per drive with 3,000 N·m brake, EP-SE419T3 provides significant safety margin above the calculated torque for even the largest rope shovels at 15° worst-case gradients. Korea Ever-Power calculates the specific torque requirement for any rope shovel configuration same day.

Ultra-Scale Offshore and Marine Heavy Crawler Platforms

The very largest tracked transport and launch platforms in offshore fabrication and marine infrastructure — systems moving pre-integrated modules, gravity base structures, and subsea infrastructure bundles above 5,000 tonnes — require EP-SE419T3 when total system weight exceeds the EP-SE418T3 service envelope. Operating in salt water, high-pressure wash environments, and marine atmospheres, the 75–100 litre oil volume and dual-cone floating metal face seals provide the contamination resistance and reserve volume needed for extended deployment cycles between maintenance windows. Auxiliary winch and mooring systems on these platforms use worm gear reducers for self-locking cable hold, independent of the EP-SE419T3 travel drives.

Super-Heavy Land Infrastructure and Civil Development

Very large tracked platforms for the most demanding civil infrastructure projects — major dam and reservoir construction at very high machine weights, large flood defence infrastructure, and major land reclamation programmes at the upper scale of heavy construction — require EP-SE419T3 where total machine weight and site resistance exceed EP-SE418T3's capability. Downstream implement drives on these platforms use agricultural and land development gearboxes on separate PTO circuits, independent of the EP-SE419T3 travel drives.

Specialised Heavy Defence and Nuclear Infrastructure Platforms

Ultra-heavy tracked platforms above 4,000 tonnes in national infrastructure, nuclear power station construction (reactor building module placement), and specialised defence and energy projects where the combination of extreme machine weight, required safety factor, and site gradient conditions demand 330,000 N·m per drive with 3,000 N·m spring brake position hold. The 2,500 rpm maximum input constraint at this torque class is already within the motor speed range of the very large-displacement motors used at this scale. Korea Ever-Power provides full engineering documentation, 3D CAD models, and hydraulic schematic recommendations for integrating this track drive planetary gearbox into new or existing hydraulic circuits at this torque class.

Motor Selection, Brake Analysis, and Ratio — Same Day

EP-SE419T3's 2,500 rpm maximum input requires motor displacement approximately 20% larger than an equivalent unit running at 3,000 rpm at the same circuit pressure. Korea Ever-Power's same-day engineering response covers motor displacement recommendation; ratio from i=161–306 for your travel speed; 3,000 N·m brake adequacy (including whether spring brake alone is sufficient or supplementary counterbalance valves are required at your machine weight and gradient); and dimensional cross-reference. Provided in one document, no charge, before any order commitment.

Pre-Assembled and 3,000 N·m Brake Verified at 2,850 kg

Korea Ever-Power provides EP-SE419T3 pre-assembled with matched large-displacement motor (2,500 rpm maximum), overcenter valve, and pressure relief valve. The 3,000 N·m brake is function-verified before shipping: spring applied (drum fully locked), pilot applied at 15–30 bar (drum free within 1.5 seconds), oil filled to correct level. At 2,850 kg requiring a ≥8,000 kg crane, on-machine brake commissioning is logistically complex and time-critical. Korea Ever-Power's pre-shipment brake function verification eliminates that risk entirely.

Stage-Level Parts — 2,850 kg Serviced In-Situ

Korea Ever-Power stocks all EP-SE419T3 internal components: Stage 1, 2, and 3 sun gear and planet set assemblies; 3,000 N·m brake disc pack (friction discs, separator plates, disc springs, O-ring kit); dual-cone floating face seal kits; taper bearing sets; housing O-ring kits. At 2,850 kg, returning this unit to any facility for component repair involves crane logistics comparable to the original installation. In-situ stage-level repair with Korea Ever-Power parts is the only practically viable maintenance approach at this scale, and Korea Ever-Power's stage-separated catalogue supports it fully.

12/18-Month Warranty — 3,000 N·m Brake Included

12 months from commissioning or 18 months from shipment, covering all three planetary stages, the 3,000 N·m brake assembly in full, and the floating face seals. Warranty component replacement dispatched from Korea Ever-Power stock — the 3,000 N·m brake disc pack and face seal kits can be dispatched in 7–14 days, covering in-situ replacement at the site without returning the unit. For OEM fleet buyers, warranty begins at commissioning.

Stock, Framework Supply, and Emergency Response

Standard configurations from Korea Ever-Power stock in 7–14 days. Pre-assembled motor packages: 30–45 days. At 2,850 kg and 330,000 N·m, an unplanned drive failure in a 7,000-tonne dragline or 24-metre TBM represents catastrophic project cost with no rapid resolution path. Korea Ever-Power discusses reserved production capacity, consignment stock, and emergency dispatch arrangements for the largest fleets at this scale. Contact Korea Ever-Power with fleet size and annual volume for framework pricing and emergency response planning at this torque class.

−25°C to +90°C — 2,850 kg Thermal Mass at 75–100 L Oil

At 2,850 kg nodular iron, thermal mass is approximately 1,425 kJ per degree — the highest in the SE series on this site, and the 75–100 litre oil volume adds substantial thermal capacity. At >93% efficiency, the absolute heat generated per kilowatt at this torque scale is managed by the largest housing in the series. For high-ambient and sustained duty-cycle applications, Korea Ever-Power provides thermal assessment on request. For operation at −25°C, the low-temperature Viton seal and grade-appropriate low-temp gear oil are pre-specified in the dimensional drawing package.

We supply crawler-based travel drive systems for the largest walking draglines built for hard rock strip mining in Eastern Europe and Central Asia — machines with operating weights between 6,500 and 9,200 tonnes. Korea Ever-Power confirmed EP-SE419T3 at i=240 for our primary design platform after our drive torque calculation — 6,800 tonnes on an 8° bench access ramp with a 1.55× shock factor — produced a required drive torque of 308,000 N·m per unit. EP-SE418T3 at 270,000 N·m was insufficient by that margin. At i=240, the 3,000 N·m spring brake provides 720,000 N·m per drive hold — our type-approval requires 2.0× the maximum calculated drive torque from spring brake alone: 720,000 vs 308,000 gives 2.34× — exceeding our standard and eliminating the need for supplementary counterbalance valves in our base specification. The 2,500 rpm motor input matched our standard large-displacement axial piston motors that already operate at approximately 2,200–2,400 rpm in our hydraulic circuit, so no motor change was required. At 1,800 hours across six units on two dragline platforms, zero EP-SE419T3 failures. Korea Ever-Power's engineering response turned around same day, with the 3,000 N·m brake calculation — the deciding document for our type-approval — included in the first response.

Our most recent project involved a 24.6-metre bore diameter TBM for a major water conveyance tunnel in India. The TBM's propel ring used 56 individual drive units. Our geotechnical analysis identified very hard granitic gneiss at the deepest tunnel section requiring peak per-unit thrust of 295,000 N·m with our 1.12× geological uncertainty factor — 330,400 N·m per unit, right at EP-SE419T3's rated limit. Korea Ever-Power confirmed that at our target advance rate of 12.4 rpm output, i=202 from the i=161–306 range was the correct selection at 2,500 rpm motor input. The 2,500 rpm input was well-matched to our existing 2,200 rpm operating point for our very large axial piston motors at full circuit pressure. At 1,100 hours of tunnelling through 3.9 km of mixed geology (including 1.4 km of the hardest granitic section at full thrust), zero EP-SE419T3 failures across all 56 drives. Our 3D CAD integration — provided by Korea Ever-Power within the engineering package — was accepted by our TBM OEM partner for the dimensional verification without modification. We maintain eight units in consignment stock at our project base, replenished by Korea Ever-Power within 14 days as consumed.

We build and operate very large tracked gantry transport systems for port and offshore fabrication yards in the Middle East. Our largest system moves pre-integrated offshore platform deck sections weighing up to 6,500 tonnes. Korea Ever-Power confirmed EP-SE419T3 at i=190 for our 20 travel drives after confirming our worst-case tractive force calculation — 6,500 tonnes on our 3° maximum yard surface gradient plus 50 kN wind load per drive — produced a per-unit requirement of 316,000 N·m, exceeding EP-SE418T3's capacity. The 3,000 N·m spring brake at i=190 provides 570,000 N·m per drive emergency hold. We operate in an extremely high humidity, salt-laden atmosphere with regular high-pressure wash-down. At 3,100 hours across 20 drives over four major load-out operations, zero EP-SE419T3 failures and zero oil contamination from the marine environment. Korea Ever-Power's 3,000 N·m brake at this scale was the primary specification criterion — we contacted four European suppliers before Korea Ever-Power; none could deliver a 330,000 N·m unit with 3,000 N·m brake from stock within 14 days. Korea Ever-Power delivered within 12 days.

QWhy is EP-SE419T3's maximum input speed 2,500 rpm when EP-SE418T3 allows 3,000 rpm?

At 330,000 N·m, EP-SE419T3's final-stage gear pitch circle diameters are larger than in EP-SE418T3 (270,000 N·m). Pitch-line velocity at the gear mesh = π × d_pitch × n / 60 governs EHL oil film thickness and tooth surface fatigue life. Maintaining the same maximum pitch-line velocity as SE418T3 at 3,000 rpm requires reducing n proportionally for the larger d_pitch in SE419T3 — resulting in 2,500 rpm maximum. If EP-SE419T3 were run at 3,000 rpm, the larger gears would produce a pitch-line velocity exceeding the safe limit for sustained operation at 330,000 N·m, leading to accelerated tooth surface fatigue. Motor displacement must increase by approximately 20% compared to a 3,000 rpm motor delivering the same power. Korea Ever-Power confirms the exact required motor displacement for your specific hydraulic circuit pressure and power in the same-day engineering enquiry response. If the motor already used with EP-SE418T3 operates at or below 2,500 rpm in your circuit at full power, no motor change is required for the upgrade.

QEP-SE419T3's maximum ratio is i=306, lower than SE418T3's i=364. Does this mean SE419T3 has a slower maximum speed?

No — the minimum output speed (at maximum ratio) is approximately the same. EP-SE418T3 at i=364 and 3,000 rpm produces 8.24 rpm. EP-SE419T3 at i=306 and 2,500 rpm produces 8.17 rpm. The deepest operational speed is essentially equivalent; the engineering path differs. EP-SE419T3 achieves slow output through lower motor speed rather than a deeper ratio. The maximum speed (at minimum ratio) is different: EP-SE418T3 at i=166 and 3,000 rpm = 18.1 rpm; EP-SE419T3 at i=161 and 2,500 rpm = 15.5 rpm. EP-SE419T3 is therefore slightly slower at its fastest operational point — consistent with the 4,000–10,000 tonne machine class it serves, where 15.5 rpm sprocket output is already the practical maximum useful travel speed.

QDoes the 3,000 N·m spring brake alone provide adequate parking hold for a 5,000-tonne machine on a steep gradient?

At higher operational ratios, yes for many gradient configurations. At i=250 (a typical working ratio for machines in the 4,000–6,000 tonne class), the spring brake equivalent is 3,000 × 250 = 750,000 N·m per drive — 1,500,000 N·m combined. For a 5,000-tonne machine at 10° gradient with 850 mm sprocket radius: rolling force = 5,000,000 × 9.81 × sin10° × 0.85 / 2 = 3,616,000 N·m combined. The spring brake at i=250 provides 1,500,000 N·m versus 3,616,000 N·m required — a safety factor of 0.41 from spring brake alone. Supplementary counterbalance valves are required at steep gradients for very heavy machines. At 5° gradient: rolling force combined = 1,815,000 N·m — spring brake at i=250 provides 1,500,000 N·m, a safety factor of 0.83 from spring brake alone; supplementary valves are still recommended for full safety margin. At i=306 and 5°: spring brake provides 1,836,000 N·m combined versus 1,815,000 N·m required — spring brake alone is marginally sufficient. Korea Ever-Power calculates the specific combined spring brake plus counterbalance valve requirement for your exact machine weight, ratio, and gradient — same day, no charge — and advises on the minimum supplementary valve specification when required.

QOil volume, first-change procedure, and condition monitoring for the 2,850 kg unit?

EP-SE419T3 contains approximately 75–100 litres of gear oil — the highest 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: drain warm — with 75–100 litres, allow 40+ minutes full drain time to evacuate all three stages. Refill with 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 every 500 hours is strongly recommended at this unit weight and value. Baseline elemental levels established at 150-hour first change are the reference for all subsequent comparisons. Korea Ever-Power provides reference baseline ranges as part of the startup documentation package, and can advise on interpreting sample results to distinguish stage-specific from bearing wear. At 75–100 litres, even a minor oil leak is detectable early through level monitoring — a simple monthly oil level check between sampling intervals is a low-effort early-warning system for any seal failure.