{"id":879,"date":"2026-06-17T06:28:10","date_gmt":"2026-06-17T06:28:10","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?post_type=product&p=879"},"modified":"2026-06-17T06:28:10","modified_gmt":"2026-06-17T06:28:10","slug":"zr35-slewing-drive-planetary-gearbox","status":"publish","type":"product","link":"https:\/\/planetary-gearboxes.com\/cs\/produkt\/zr35-slewing-drive-planetary-gearbox\/","title":{"rendered":"ZR35 Slewing Drive Planetary Gearbox \u2014 Right-Angle Bevel-Planetary, 3-5 Stage"},"content":{"rendered":"
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<\/p>\n

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EP-ZR35 \u2014 Near-Flagship Torque with Full Ratio Flexibility<\/h2>\n
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\"Korea<\/p>\n

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34,500<\/div>\n
Max Cont. Nm<\/div>\n<\/div>\n
\n
64,500<\/div>\n
Peak Nm<\/div>\n<\/div>\n
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67+<\/div>\n
Configurations<\/div>\n<\/div>\n
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3-5<\/div>\n
F\u00e1ze<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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Ten\/Ta\/To EP-ZR35<\/strong> answers the question engineers regularly face at the top of the ZR slewing drive series<\/a>: what if you need near-ZR45 torque capacity but the ZR45 only offers three fixed gear ratios? The ZR35 resolves this by delivering 34,500 Nm continuous torque \u2014 81% of the ZR45 rating \u2014 across more than 67 ratio configurations spanning three stage counts (3-stage, 4-stage, and 5-stage). For the vast majority of applications in the 27,500-34,500 Nm class, the ZR35 provides the precise ratio match that the ZR45 cannot.<\/p>\n

The 5-stage configurations extend the ratio range to 4,460:1 for ultra-low-speed heavy positioning, while the 3-stage ratios at 43:1-108:1 provide high-speed, high-thermal-capacity slewing for continuous-duty port crane and mining equipment applications. Three torque tiers (34,500 \/ 34,000 \/ 27,500 Nm) accommodate the full ratio span with graduated de-rating at the highest reduction values.<\/p>\n

IP67 Sealed<\/span>
\nDIN 5-6<\/span>
\n-40 to +80 deg C<\/span>
\n3,000 RPM Max<\/span>
\nPt 21.5-26.0 kW<\/span><\/div>\n<\/div>\n<\/div>\n<\/section>\n
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ZR35 Technical Parameters \u2014 67+ Ratio Configurations<\/h2>\n

Continuous torque at N2 x h = 100,000 hours. The ZR35 uses three torque tiers: 34,500 Nm (primary), 34,000 Nm (3-stage low ratios), and 27,500 Nm (highest ratios). All configurations share 3,000 rpm maximum input speed. Due to the large number of available configurations, the summary table below groups ratios by stage count and torque tier.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n
F\u00e1ze<\/th>\nRozsah pom\u011br\u016f<\/th>\nOptions<\/th>\nCont. Torque (Nm)<\/th>\nMax. Torque (Nm)<\/th>\nMax RPM<\/th>\nPt F\/M (kW)<\/th>\n<\/tr>\n<\/thead>\n
3stup\u0148ov\u00fd<\/td>\n43.06 \u2013 108.76<\/td>\n8<\/td>\n34,000<\/td>\n64,500<\/td>\n3,000<\/td>\n25.5 \/ 26.0<\/td>\n<\/tr>\n
117.55 \u2013 139.59<\/td>\n2<\/td>\n27,500<\/td>\n55,500<\/td>\n3,000<\/td>\n25.5 \/ 26.0<\/td>\n<\/tr>\n
4-Stage<\/td>\n117.55 \u2013 388.08<\/td>\n19<\/td>\n34,500<\/td>\n64,500<\/td>\n3,000<\/td>\n21.5 \/ 22.5<\/td>\n<\/tr>\n
416.23 \u2013 734.53<\/td>\n8<\/td>\n27,500<\/td>\n55,500<\/td>\n3,000<\/td>\n21.5 \/ 22.5<\/td>\n<\/tr>\n
5-Stage<\/td>\n463.33 \u2013 2,113.10<\/td>\n26<\/td>\n34,500<\/td>\n64,500<\/td>\n3,000<\/td>\n21.5 \/ 22.5<\/td>\n<\/tr>\n
2,342.91 \u2013 4,459.76<\/td>\n4<\/td>\n27,500<\/td>\n55,500<\/td>\n3,000<\/td>\n21.5 \/ 22.5<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

79% of all ZR35 configurations (53 of 67) deliver 34,000-34,500 Nm continuous without de-rating. Full per-ratio data sheet available on request from Korea Ever-Power engineering<\/a>.<\/p>\n<\/section>\n

<\/p>\n

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Spare Parts and Field-Serviceable Components<\/h2>\n

The ZR35 is designed with modular accessibility in mind: certain components can be replaced on-site by a trained technician without removing the gearbox from the machine. Others require factory disassembly. Knowing the difference before an issue arises reduces downtime and prevents well-intentioned field repairs from causing secondary damage.<\/p>\n

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\u2705 Field-Replaceable (On-Site)<\/h3>\n
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Output Shaft Seal<\/strong><\/p>\n

FKM multi-lip seal, replaceable without gearbox removal. Requires a seal installation sleeve (included with the seal kit) and clean working conditions. Estimated field time: 2-4 hours including oil drain and refill.<\/p>\n<\/div>\n

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Input Shaft Seal<\/strong><\/p>\n

Accessible after removing the motor or input coupling. Same FKM material and installation procedure as the output seal. Order the correct seal kit for your input flange variant (BF, IS, or IEC).<\/p>\n<\/div>\n

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Breather Valve<\/strong><\/p>\n

Threaded replacement, no tools other than a wrench. Replace if blocked, contaminated, or physically damaged. Always carry a spare on-site for remote installations.<\/p>\n<\/div>\n

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Fail-Safe Brake Assembly<\/strong><\/p>\n

The B-series spring-applied brake is a bolt-on module. The complete brake assembly (disc, springs, piston, and housing) can be replaced as a unit in the field. Estimated time: 3-5 hours. Brake disc-only replacement requires a press and is recommended as a workshop task.<\/p>\n<\/div>\n

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Gear Oil<\/strong><\/p>\n

PAO synthetic ISO VG 220 (standard). Drain via the drain plug, refill via the fill port. Oil volume for the ZR35 is approximately 8-12 litres depending on stage count and mounting orientation.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

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\u274c Factory Service Required<\/h3>\n
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Planetary Gear Sets<\/strong><\/p>\n

Internal gear replacement requires complete disassembly, bearing preload re-setting, and backlash verification on a test bench. Attempting gear replacement in the field without proper tooling and measurement equipment risks misalignment and accelerated failure of the new components.<\/p>\n<\/div>\n

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Output and Input Bearings<\/strong><\/p>\n

Tapered roller bearings require precision preloading during reassembly. Incorrect preload (too tight or too loose) directly causes premature bearing failure. Factory overhaul includes new bearings, seals, and a full load test before return.<\/p>\n<\/div>\n

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Bevel Input Stage<\/strong><\/p>\n

The spiral bevel gear pair requires matched lapping and contact pattern verification that can only be performed with factory gear testing equipment. Bevel gear damage always requires a factory return for overhaul.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Where the ZR35 Outperforms the Alternatives<\/h2>\n

\"Heavy-duty<\/p>\n

\n
\n

Heavy Port Cranes (30-60 Tonne Lifting Class)<\/h3>\n

Harbour mobile cranes, ship-to-shore feeder cranes, and floating cranes in the 30-60 tonne lifting class generate slewing torques of 25,000-34,000 Nm during full-load boom rotation. The ZR35 3-stage at ratios 53:1-100:1 delivers the high thermal capacity (25.5-26.0 kW) that continuous port operations demand, while the 67+ ratio options ensure the optimal motor-gearbox pairing without compromising to the nearest available ratio. Dual-drive arrangements using two ZR35 units can reach 69,000 Nm combined continuous for the largest feeder crane installations.<\/p>\n<\/div>\n

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Mining Excavators and Draglines (50-80 Tonne)<\/h3>\n

Excavators and draglines in the 50-80 tonne class generate sustained slewing torques that fall between the ZR30 (32,000 Nm) and ZR45 (42,500 Nm) capacities. The ZR35 fills this gap precisely, providing 34,500 Nm continuous with a 2:1 peak-to-continuous ratio (64,500 Nm peak) that absorbs the aggressive shock loads from bucket strikes and emergency reversals. The EP-SE track drive series<\/a> provides matching undercarriage propulsion for these machines.<\/p>\n<\/div>\n

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Large Boring Machines and Foundation Equipment<\/h3>\n

Large-diameter bored piling rigs, diaphragm wall grab cranes, and cutter-soil mixing equipment require high torque at controlled low speeds for tool rotation and mast positioning. The ZR35 5-stage at ratios 463:1-2,113:1 provides the creep-speed rotation these heavy foundation machines<\/a> demand, with the full 34,500 Nm available across the majority of the 5-stage ratio range. The IP67 sealing withstands the bentonite slurry, concrete wash, and groundwater inherent in foundation construction.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Project Documentation \u2014 What Ships and What Is Available on Request<\/h2>\n

Heavy-duty slewing drive installations typically require extensive documentation for machine certification, insurance, and operational compliance. The ZR35 documentation package covers the needs of OEM crane manufacturers, mining fleet operators, and classification societies.<\/p>\n

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Included with Every Unit<\/h3>\n
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Serial Number Certificate<\/strong> \u2014 unique serial laser-engraved on housing, linked to full production record<\/p>\n

Dimensional Inspection Report<\/strong> \u2014 critical interface dimensions (shaft, flange, bolt holes) measured and recorded against drawing tolerance<\/p>\n

Material Heat Certificates (EN 10204 3.1)<\/strong> \u2014 for all gear steels and bearing components, traceable to the steel mill melt number<\/p>\n

Load Test Report<\/strong> \u2014 factory dynamometer test at rated torque for minimum 30 minutes, recording oil temperature rise, vibration, and noise<\/p>\n

Installation, Operation and Maintenance Manual<\/strong> \u2014 specific to the ordered configuration, including oil fill volumes for each mounting orientation<\/p>\n<\/div>\n<\/div>\n

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Available on Request<\/h3>\n
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Classification Society Witnessed Testing<\/strong> \u2014 DNV, Lloyd, BV, ABS, CCS witness at our facility; add 4-6 weeks to lead time<\/p>\n

2D\/3D CAD Drawings<\/strong> \u2014 general arrangement, sectional, and interface drawings in DWG, STEP, or IGES format; typically delivered within 48 hours of enquiry<\/p>\n

FEA Stress Analysis Report<\/strong> \u2014 finite element analysis of housing and gear tooth contact stress at specified operating conditions<\/p>\n

Gear Contact Pattern Photographs<\/strong> \u2014 photos of the factory contact pattern check using marking compound, for customer quality verification<\/p>\n

Bearing Life Calculation Report<\/strong> \u2014 L10 bearing life prediction based on the application-specific radial, axial, and moment loads provided by the customer<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Souvisej\u00edc\u00ed produkty<\/h2>\n
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\"SE401T1<\/p>\n

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Track Drive Planetary Gearboxes \u2192<\/a><\/h3>\n

EP-SE heavy-duty track drives for 50-80 tonne excavator and dragline crawler undercarriage propulsion.<\/p>\n<\/div>\n<\/div>\n

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\"EP-ZDS<\/p>\n

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High-Precision Planetary Gearboxes \u2192<\/a><\/h3>\n

EP-ZDS series for crane hoist servo drives, boring machine cutter-head positioning, and heavy equipment automated controls.<\/p>\n<\/div>\n<\/div>\n

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\"Heavy<\/p>\n

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Agricultural Gearboxes \u2192<\/a><\/h3>\n

Right-angle bevel stages for port conveyor head drives, mining auxiliary mechanisms, and foundation equipment slurry pump drives.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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\u010casto kladen\u00e9 ot\u00e1zky<\/h2>\n
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When should I choose the ZR35 over the ZR30 or ZR45?<\/h3>\n

Choose the ZR35 when: (a) continuous torque requirement exceeds 32,000 Nm (the ZR30 maximum), or (b) the application needs more ratio flexibility than the ZR45 offers (3 fixed ratios). The ZR35 provides 81% of the ZR45 torque with 22 times more ratio options. If your torque falls below 32,000 Nm, the ZR30 at 58 ratios is a more compact and cost-effective solution. If torque must exceed 34,500 Nm or peak loads exceed 64,500 Nm, the ZR45 is the only option.<\/p>\n<\/div>\n

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What is the expected lead time for the ZR35?<\/h3>\n

Standard lead time is 6-8 weeks from order confirmation. The 4-stage configurations are the most commonly produced and may ship in 5-6 weeks if component stock is available. Units requiring custom output pinions, classification society witnessed testing, or non-standard coatings should allow 10-14 weeks. Emergency replacement units can be expedited \u2014 contact our team directly to discuss accelerated production options.<\/p>\n<\/div>\n

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Can I order replacement seals and brake discs directly?<\/h3>\n

Yes. Seal kits, breather valves, brake assemblies, and brake disc replacements are available as separate spare part orders. Quote the ZR35 serial number (engraved on the housing) and the component required. Seal kits typically ship within 1-2 weeks; brake assemblies within 3-4 weeks. We recommend keeping one seal kit and one breather valve per unit as on-site spares for remote or high-criticality installations.<\/p>\n<\/div>\n

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Does Korea Ever-Power offer factory overhaul service for the ZR35?<\/h3>\n

Yes. Units returned for factory overhaul undergo complete disassembly, inspection, cleaning, and measurement against original manufacturing tolerances. Worn gears, bearings, and seals are replaced. The overhauled unit receives a full load test identical to a new unit and ships with a fresh documentation package. Typical overhaul turnaround is 4-6 weeks from receipt at our facility. The overhaul cost is typically 40-55% of a new unit price depending on the condition of the gears and housing.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Customer Feedback<\/h2>\n
\n
\n
\n
J<\/div>\n
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James W. \u2014 Port Equipment Director<\/div>\n
Verified Purchase \u00b7 Felixstowe, UK \u00b7 April 2026<\/div>\n<\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n<\/div>\n

Dual ZR35**3 at ratio 70.40 on a 45-tonne harbour mobile crane. We selected the ZR35 over the ZR45 specifically because we needed a ratio close to 70:1 and the ZR45 only offers 14.19, 43.43, and 109.70. The 70.40 ratio from the ZR35 table was an exact match for our hydraulic circuit design. Combined continuous torque of 68,000 Nm is well within our requirement. Documentation package passed our internal QA review and the port authority inspection without any issues.<\/p>\n<\/div>\n

\n
\n
A<\/div>\n
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Aleksei K. \u2014 Mining Fleet Supervisor<\/div>\n
Verified Purchase<\/div>\n<\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n<\/div>\n

Replacement slewing drive on a 65-tonne excavator. The previous drive had been in service for 9 years and was ready for overhaul. We compared the overhaul quote against a new ZR35 and the new unit was only 60% more than the overhaul cost with a full warranty. Installed and commissioned in two days. Oil analysis at 2,000 hours looks clean. We have ordered the spare seal kit and breather valve as recommended \u2014 keeping them in the machine toolbox so they are available if needed at the pit face.<\/p>\n<\/div>\n

\n
\n
T<\/div>\n
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Tomasz B. \u2014 Foundation Works Manager<\/div>\n
Verified Purchase \u00b7 June 2026<\/div>\n<\/div>\n
\u2605\u2605\u2605\u2605\u2606<\/div>\n<\/div>\n

Large-diameter bored pile rig, ZR35**5 at 691.88 ratio. The drive works well for our application and the torque delivery is smooth at very low speeds. The 4-star rating is because the 3D CAD model we received was for the 4-stage variant instead of the 5-stage we ordered. The correct model arrived four days later after we flagged it. A small mix-up but on a project where our structural designer was waiting for the model to finalise the crane base steel, the delay cost us a day of fabrication scheduling. Product itself has been faultless.<\/p>\n<\/div>\n<\/div>\n<\/section>\n<\/div>","protected":false},"excerpt":{"rendered":"

The EP-ZR35 Planetary gearbox is the penultimate frame in the Korea Ever-Power ZR slewing drive series, positioned directly below the ZR45 flagship. Delivering up to 34,500 Nm continuous output torque and 64,500 Nm peak across 67+ ratio configurations spanning 3-stage through 5-stage planetary reductions (43.06 to 4,460), the ZR35 combines near-flagship torque capacity with the wide ratio selection that the ZR45 cannot provide. Applications include heavy port cranes (30-60 tonne class), mining dragline and shovel mechanisms, large offshore platform equipment, and heavy boring machine drives. IP67 FKM sealed, DIN 5-6, QT600-3 ductile iron, -40 to +80 deg C.<\/div>","protected":false},"featured_media":880,"comment_status":"open","ping_status":"closed","template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[967],"product_tag":[],"class_list":["post-879","product","type-product","status-publish","has-post-thumbnail","product_cat-slewing-drive-planetary-gearbox","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/product\/879","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/comments?post=879"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/media\/880"}],"wp:attachment":[{"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/media?parent=879"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/product_brand?post=879"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/product_cat?post=879"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/cs\/wp-json\/wp\/v2\/product_tag?post=879"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}