{"id":191,"date":"2026-07-09T08:09:24","date_gmt":"2026-07-09T08:09:24","guid":{"rendered":"https:\/\/industrialelectricmotor.net\/?post_type=product&p=191"},"modified":"2026-07-09T08:09:25","modified_gmt":"2026-07-09T08:09:25","slug":"r-series-inline-helical-gear-reducer","status":"publish","type":"product","link":"https:\/\/industrialelectricmotor.net\/zh\/product\/r-series-inline-helical-gear-reducer\/","title":{"rendered":"R Series Inline Helical Gear Reducer"},"content":{"rendered":"
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Coaxial Inline Drive<\/div>\n
98% Stage Efficiency<\/div>\n
IEC B5 Motor Flange<\/div>\n
Hollow Shaft Option<\/div>\n
IP55 Protection<\/div>\n
ISO 9001 Certified<\/div>\n<\/div>\n
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\"R
\n\"R<\/div>\n
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High-Efficiency Coaxial Helical Reducer for Heavy Continuous Duty<\/h2>\n

The R series inline helical gear reducer is a multi-stage coaxial gearbox in which motor input shaft and load output shaft share the same centreline. This inline geometry simplifies machine layout by eliminating the offset between motor and load shafts that is inherent in right-angle gearboxes, and it allows the motor to be coupled directly to the gearbox input without an intermediate coupling shaft or coupling spacer.<\/p>\n

Helical gear stages achieve efficiency of up to 98% per stage because the gradual tooth engagement of helical gears (teeth mesh along a diagonal line rather than a point) reduces impact loading, noise, and sliding friction compared to spur gears or worm gears at the same ratio. A two-stage R series gearbox achieves overall efficiency of approximately 96%, and a three-stage unit approximately 94% \u2014 versus 48 to 58% for a worm gearbox at the same overall ratio. For a 15 kW drive running 16 hours per day, the energy saving of a three-stage R series versus a worm gearbox at 50:1 ratio can exceed 6,000 kWh per year at the load shaft.<\/p>\n

The housing is spheroidal graphite cast iron (GJL-250 or GJS-400), providing high rigidity and excellent thermal conductivity. Gear teeth are case-hardened 20CrMnTi alloy steel, profile-ground to ISO accuracy grade 6 after heat treatment. All bearing arrangements use taper roller bearings or angular contact ball bearings to handle the combined radial and axial loads generated by helical gear thrust forces.<\/p>\n

Explore matched motors on the Three-Phase Induction Motors<\/a> page, or see the full reducer range at Helical Gear Reducers<\/a>.<\/p>\n<\/div>\n<\/div>\n

R Series Size and Performance Data<\/h2>\n

Performance data at rated input speed 1440 rpm (4-pole motor). 2-stage and 3-stage configurations available per size. Output torque values shown are maximum for that housing size.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Size<\/th>\nStages<\/th>\nRatio Range<\/th>\nMax Output Torque (N\u00b7m)<\/th>\nEfficiency (%)<\/th>\nIEC Motor Frames<\/th>\nMax Input kW<\/th>\nWeight (kg)<\/th>\n<\/tr>\n<\/thead>\n
R17<\/td>\n2<\/td>\n3.77 \u2013 24.35<\/td>\n85<\/td>\n96<\/td>\n63, 71, 80<\/td>\n0.75<\/td>\n2.5<\/td>\n<\/tr>\n
R27<\/td>\n2<\/td>\n3.77 \u2013 24.35<\/td>\n130<\/td>\n96<\/td>\n71, 80, 90<\/td>\n1.5<\/td>\n4.2<\/td>\n<\/tr>\n
R37<\/td>\n2<\/td>\n3.77 \u2013 24.35<\/td>\n200<\/td>\n96<\/td>\n80, 90, 100<\/td>\n2.2<\/td>\n6.8<\/td>\n<\/tr>\n
R47<\/td>\n2 \/ 3<\/td>\n3.77 \u2013 289.74<\/td>\n300<\/td>\n94 \u2013 96<\/td>\n90, 100, 112<\/td>\n3.0<\/td>\n11.0<\/td>\n<\/tr>\n
R57<\/td>\n2 \/ 3<\/td>\n3.77 \u2013 289.74<\/td>\n500<\/td>\n94 \u2013 96<\/td>\n100, 112, 132<\/td>\n5.5<\/td>\n18.0<\/td>\n<\/tr>\n
R67<\/td>\n2 \/ 3<\/td>\n3.77 \u2013 289.74<\/td>\n800<\/td>\n94 \u2013 96<\/td>\n112, 132, 160<\/td>\n7.5<\/td>\n26.0<\/td>\n<\/tr>\n
R77<\/td>\n2 \/ 3<\/td>\n5.21 \u2013 289.74<\/td>\n1,300<\/td>\n94 \u2013 96<\/td>\n132, 160, 180<\/td>\n15<\/td>\n42.0<\/td>\n<\/tr>\n
R87<\/td>\n2 \/ 3<\/td>\n5.21 \u2013 289.74<\/td>\n2,000<\/td>\n94 \u2013 96<\/td>\n160, 180, 200<\/td>\n22<\/td>\n62.0<\/td>\n<\/tr>\n
R97<\/td>\n2 \/ 3<\/td>\n5.21 \u2013 289.74<\/td>\n3,000<\/td>\n94 \u2013 96<\/td>\n180, 200, 225<\/td>\n37<\/td>\n88.0<\/td>\n<\/tr>\n
R107<\/td>\n2 \/ 3<\/td>\n5.21 \u2013 289.74<\/td>\n4,800<\/td>\n94 \u2013 96<\/td>\n200, 225, 250<\/td>\n55<\/td>\n128.0<\/td>\n<\/tr>\n
R137<\/td>\n2 \/ 3<\/td>\n5.21 \u2013 289.74<\/td>\n9,000<\/td>\n94 \u2013 96<\/td>\n225, 250, 280<\/td>\n90<\/td>\n210.0<\/td>\n<\/tr>\n
R167<\/td>\n2 \/ 3<\/td>\n5.21 \u2013 289.74<\/td>\n18,000<\/td>\n94 \u2013 96<\/td>\n280, 315<\/td>\n160<\/td>\n380.0<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
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Gearbox Specifications<\/h3>\n\n\n\n\n\n\n\n\n\n\n
Gear material<\/td>\n20CrMnTi case-hardened<\/td>\n<\/tr>\n
Tooth accuracy<\/td>\nISO 1328 Grade 6<\/td>\n<\/tr>\n
Housing material<\/td>\nGJL-250 cast iron<\/td>\n<\/tr>\n
Gear oil<\/td>\nISO VG 220 synthetic<\/td>\n<\/tr>\n
Protection<\/td>\nIP55<\/td>\n<\/tr>\n
Thermal limit<\/td>\n100 \u00b0C oil temperature<\/td>\n<\/tr>\n
Paint<\/td>\nRAL 5010 blue epoxy<\/td>\n<\/tr>\n
Mounting<\/td>\nAny orientation<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
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Input and Output Configurations<\/h3>\n\n\n\n\n\n\n\n\n\n\n
Input type<\/td>\nIEC B5 flange direct<\/td>\n<\/tr>\n
Output shaft<\/td>\nSolid keyed (standard)<\/td>\n<\/tr>\n
Hollow shaft<\/td>\nShrink disc option<\/td>\n<\/tr>\n
Output flange<\/td>\nAvailable R47 and above<\/td>\n<\/tr>\n
Shaft position<\/td>\nCoaxial inline<\/td>\n<\/tr>\n
Torque arm<\/td>\nIncluded with hollow shaft<\/td>\n<\/tr>\n
IEC frame range<\/td>\n63 \u2013 315<\/td>\n<\/tr>\n
Standards<\/td>\nISO 9001 \/ CE<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n

Typical Applications for R Series Helical Gear Reducers<\/h2>\n\n\n\n
\"R<\/p>\n
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Belt Conveyor Drives<\/div>\n
Long-distance belt conveyors in mining, quarrying, and aggregate handling plants use R series inline helical reducers for the combination of high output torque, high efficiency (minimising conveyor power consumption at full load), and coaxial geometry that simplifies head-pulley drive shaft alignment.<\/div>\n<\/div>\n<\/td>\n
\"R<\/p>\n
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Industrial Mixers and Agitators<\/div>\n
Large vessel agitators and industrial mixers for chemical, petrochemical, and water treatment applications use R series reducers for their high output torque capacity and the hollow shaft option that allows the agitator shaft to pass directly through the gearbox output without a coupling flange.<\/div>\n<\/div>\n<\/td>\n
\"R<\/p>\n
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Textile and Winding Machines<\/div>\n
Yarn winding machines, rope stranding machines, and wire drawing lines use R series reducers for their high efficiency at partial load and the quiet helical gear mesh that eliminates the gear-tooth noise that would otherwise affect delicate fibre tension control systems.<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n
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\u2699<\/div>\n
Screw and Auger Drives<\/div>\n
Screw conveyors, extruder feed augers, and grain auger drives use the R series hollow shaft configuration to mount directly on the auger shaft without a coupling, eliminating shaft alignment requirements and reducing overall drive train length in installations with limited axial space.<\/div>\n<\/div>\n<\/td>\n
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Hoist and Lifting Drives<\/div>\n
Industrial hoists and goods lifts use R series reducers for their high efficiency at load-bearing ratios, the ability to combine with an electromagnetic brake motor for load holding, and the high output torque capacity relative to gearbox weight compared to worm alternatives.<\/div>\n<\/div>\n<\/td>\n
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\ud83c\udfed<\/div>\n
Cooling Tower Fan Drives<\/div>\n
Cooling tower fan drive reducers use the R series for the combination of high efficiency (reducing cooling tower fan power consumption) and the hollow shaft configuration that allows the fan shaft to pass through the gearbox without a coupling, simplifying the mechanical arrangement at the top of the tower structure.<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
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R Series vs Worm Gearbox: When to Choose Each<\/h2>\n
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Efficiency at Continuous Duty<\/h3>\n

For continuous-duty drives running more than 8 hours per day, the energy saving of the R series over a worm gearbox is significant. At 50:1 ratio, a three-stage R series achieves approximately 94% efficiency versus 52% for a worm gearbox. For a 15 kW motor running continuously, this difference is approximately 6,300 kWh saved per 8,000-hour operating year \u2014 representing a typical energy cost saving of 500 to 800 USD per year per drive at industrial electricity rates, which typically recoups the higher purchase cost of the helical gearbox within 12 to 24 months of operation.<\/p>\n<\/div>\n

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Output Shaft Direction<\/h3>\n

The R series is coaxial: motor and load shafts share the same centreline. This makes it directly compatible with inline drive applications such as conveyor head pulleys, pump shafts, and auger shafts, where the motor must be positioned behind the driven shaft. For 90\u00b0 right-angle drives (motor at right angles to the load shaft), the F series parallel shaft helical gearbox or the K series bevel-helical gearbox is the appropriate choice. The worm gearbox remains the most compact right-angle option for lower duty or space-constrained applications.<\/p>\n<\/div>\n

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Load Holding and Back-Driveability<\/h3>\n

The R series helical gearbox is back-driveable at all ratios \u2014 the load can back-drive the input shaft if the motor is de-energised. This is the correct behaviour for most conveyor and mixer applications where the motor is the only power source and the driven load is essentially passive. For applications requiring load holding (inclined conveyors, lifts, gates), an electromagnetic brake motor must be used with the R series to hold the load when the motor stops. The worm gearbox is self-locking above 30:1, so does not require a separate brake for load holding in those applications.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

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\"Korea<\/p>\n
Production Facility<\/div>\n<\/div>\n
\"Korea<\/p>\n
QC Inspection<\/div>\n<\/div>\n
\"Korea<\/p>\n
Global Shipping<\/div>\n<\/div>\n
\"Korea<\/p>\n
CE and ISO Certifications<\/div>\n<\/div>\n<\/div>\n<\/div>\n

Frequently Asked Questions \u2014 R Series Helical Gear Reducer<\/h2>\n
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What is the difference between the R series and the F, K, and S series helical gearboxes?<\/div>\n
The R series is inline (coaxial): input and output shafts share the same centreline, making it suitable for end-to-end conveyor, pump, and auger drives. The F series is parallel shaft: input and output shafts are parallel but offset, making it suitable for drives where the motor must be positioned alongside the load shaft rather than behind it. The K series is bevel-helical: a bevel gear first stage provides a 90\u00b0 right-angle change of shaft direction with higher efficiency than a worm first stage, followed by helical stages for further reduction \u2014 combining right-angle geometry with high efficiency. The S series is helical-worm: a helical first stage drives a worm second stage, providing the compact right-angle geometry of the worm gearbox with higher efficiency than a single-stage worm at the same ratio.<\/div>\n<\/div>\n
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What oil fill is supplied and when should it be changed?<\/div>\n
R series gearboxes are supplied filled with synthetic ISO VG 220 gear oil as standard. The first oil change is recommended at 500 operating hours to flush running-in particles. Thereafter, oil change intervals of 10,000 hours (or 5 years) apply for synthetic lubricant in normal operating conditions. For gearboxes running continuously above 80 \u00b0C oil temperature, intervals should be halved. Always verify the oil level through the level plug before commissioning and after any period of storage. The oil volume for each size is marked on the identification plate. Use only the lubricant grade specified for the size and mounting orientation used.<\/div>\n<\/div>\n
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Can R series gearboxes be installed with the output shaft pointing vertically downward?<\/div>\n
Yes. The R series can be installed in all mounting orientations including vertical output shaft upward and downward, horizontal with the motor above or below, and inclined at any angle. For non-horizontal mounting positions, the oil fill level must be adjusted to maintain correct oil depth at each bearing and gear stage. Korea Ever-Power provides an orientation code in the order reference (M1 through M6 per IEC standard mounting position designations) and confirms the correct fill level for the specified orientation on the gearbox identification plate and in the supplied instruction documentation.<\/div>\n<\/div>\n
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Is the hollow shaft option available for all R series sizes?<\/div>\n
The hollow shaft (shrink disc) output configuration is available for R series sizes R37 and above. The hollow shaft bore accepts driven equipment shafts from 20 mm to 120 mm depending on gearbox size, and the shrink disc provides a keyless interference fit that can transmit the full rated output torque without a key or keyway in the driven shaft. A torque reaction arm is supplied with all hollow shaft variants to absorb the reaction torque at the gearbox body. For R17 and R27, only solid shaft output is available in the standard range due to the small hub dimensions at these sizes.<\/div>\n<\/div>\n
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What is the maximum overhung load permissible on the R series output shaft?<\/div>\n
Permissible overhung load (radial force applied at the shaft extension midpoint) ranges from 1,800 N for R17 to over 40,000 N for R167. Exceeding the permissible overhung load causes premature output shaft bearing failure and must be avoided. For sprocket or pulley drives where significant radial force is applied to the shaft, the load position along the shaft extension and the magnitude of the belt or chain tension must be checked against the permissible overhung load table provided in the gearbox selection catalogue. Korea Ever-Power application engineers can verify overhung load compliance for specific drive arrangements on request.<\/div>\n<\/div>\n<\/div>\n
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Request a Quote for R Series Helical Gear Reducers<\/h2>\n

Specify gearbox size, ratio, output shaft type, mounting orientation, and motor frame. Learn about our manufacturing on the About Us<\/a> page.<\/p>\n

Contact Korea Ever-Power<\/a><\/p>\n<\/div>\n

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

\n

Coaxial inline helical gear reducer with IEC B5 motor input flange and solid or hollow output shaft, available in sizes R17 through R167. Multi-stage helical gearing delivers efficiency up to 98% per stage, making the R series the preferred specification for high-duty-cycle conveyor drives, heavy mixer drives, and continuous industrial process drives where energy efficiency and low operating temperature are primary requirements.<\/p>\n

Sizes: R17 \u2013 R167<\/span>
\nRatios: 3.77 \u2013 289.74<\/span>
\nOutput Torque: 85 \u2013 18,000 N\u00b7m<\/span>
\nEfficiency: up to 98% per stage<\/span>
\nInline \/ Coaxial Output<\/span>
\nIP55 Protection<\/span><\/div>\n<\/div>","protected":false},"featured_media":25,"template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[23],"product_tag":[],"class_list":["post-191","product","type-product","status-publish","has-post-thumbnail","product_cat-helical-gear-reducers","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/product\/191","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/types\/product"}],"wp:attachment":[{"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/media?parent=191"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/product_brand?post=191"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/product_cat?post=191"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/industrialelectricmotor.net\/zh\/wp-json\/wp\/v2\/product_tag?post=191"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}