Planetary Reducer and Precision Gear Components — Custom Manufacturing to Customer Specification

SMI manufactures planetary reducers and precision gear components to customer drawing and technical specification — covering gear cutting, precision machining, heat treatment and assembly. Planetary reducer configurations cover a wide ratio range with multiple output shaft options, supplied to industrial equipment manufacturers and OEM customers in heavy machinery, mining, energy and marine sectors.

As with all SMI mechanical component supply, finished products are produced to the customer’s own engineering drawing or specification. SMI does not supply standard catalogue reducers — every configuration is engineered to the specific ratio, torque, shaft geometry and mounting requirements of the customer’s application.

---

Planetary Reducer — Configuration and Capability

A planetary gear system consists of a central sun gear, a set of planet gears rotating around it, a ring gear enclosing the assembly, and a planet carrier transmitting the output torque. The compact, coaxial layout of the planetary system delivers high torque density relative to its physical size — making it the preferred reducer configuration for space-constrained and high-torque applications across heavy industry.

Standard Configuration Range

Parameter	Range	Notes
Gear ratio	3:1 — 400:1	Single and multi-stage configurations
Output torque	Up to 2,000 N.m	Higher torque on request
Output shaft type	Square, hexagonal, flange	Custom shaft geometry available
Custom configurations	All parameters	To customer drawing and specification

Custom configurations outside the standard range — higher torque ratings, alternative shaft dimensions, modified mounting geometry or specific material grades — are available on request. SMI application engineers will confirm the appropriate configuration at the enquiry stage.

---

Components Manufactured

The image above shows four core planetary reducer components manufactured by SMI — illustrating the precision machining capability applied across the full component set:

• Output flange / planet carrier flange — precision bolt circle and mating face, machined to assembly drawing tolerances
• Ring gear — internal gear cutting to specified module, tooth profile and accuracy grade
• Planet carrier assembly — bearing bore machining, planet pin holes and structural body
• Planet gear shaft assembly — external gear cutting, shaft journals and spline features to drawing

---

Herringbone Gear Capability

In addition to planetary reducer components, SMI manufactures herringbone gears — a double helical gear configuration where two sets of oppositely angled helical teeth are combined side by side. The herringbone geometry cancels the axial thrust loads inherent in single helical gears, allowing high power transmission without the substantial thrust bearing requirements that helical gears impose. This characteristic makes herringbone gears particularly well suited to high-torque gearboxes in heavy machinery and marine propulsion applications.

Herringbone gears are more demanding to manufacture than equivalent spur or helical gears — requiring precise alignment of the opposing helical flanks at the centreline junction. SMI’s gear cutting capability covers this geometry, with finished gears supplied to the accuracy grade and material specification required by the customer’s application.

---

Applications

• Mining and mineral processing equipment — conveyors, mills, hoists and crushing machinery
• Heavy industrial machinery — presses, mixers, extruders and material handling equipment
• Energy sector — wind turbine pitch and yaw drives, oil and gas pumping systems
• Marine propulsion and auxiliary machinery — where herringbone gear capability is directly relevant
• Construction equipment — tracked vehicles, cranes and lifting machinery
• Agricultural and forestry machinery — high-torque drive systems

---

OEM and Custom Supply

SMI’s planetary reducer and gear component manufacturing service is available to equipment manufacturers requiring:

• Component supply to drawing — individual gear components produced to the customer’s engineering drawing or CAD model
• Complete reducer assembly — fully assembled and tested planetary reducer to customer specification
• Gear cutting to specification — module, tooth profile, accuracy grade and material to customer requirement
• Heat treatment — case hardening, through hardening or nitriding to specified surface hardness and case depth
• Spare parts supply — replacement gear components alongside new equipment orders

---

بالعربية — مخفضات الكوكبية ومكونات التروس الدقيقة

تقوم SMI بتصنيع مخفضات السرعة الكوكبية ومكونات التروس الدقيقة وفقاً لرسومات العملاء والمواصفات التقنية. تغطي نسب التخفيض من 3:1 إلى 400:1، مع عزم دوران للإخراج يصل إلى 2000 نيوتن متر. تتوفر تكوينات مخصصة لتطبيقات الآلات الثقيلة والتعدين والطاقة. للاستفسار، تواصل مع فريق SMI →

---

En Español — Reductores Planetarios y Componentes de Engranajes de Precisión

SMI fabrica reductores planetarios y componentes de engranajes de precisión según los planos y especificaciones técnicas del cliente. Las relaciones de reducción cubren de 3:1 a 400:1, con par de salida de hasta 2.000 N.m. Se encuentran disponibles configuraciones personalizadas para aplicaciones en maquinaria pesada, minería y sector energético. Para consultas, contacte al equipo de SMI →

---

Auf Deutsch — Planetengetriebe und Präzisionszahnradkomponenten

SMI fertigt Planetengetriebe und Präzisionszahnradkomponenten nach Kundenzeichnung und technischer Spezifikation. Die Übersetzungsverhältnisse reichen von 3:1 bis 400:1, mit einem Ausgangsdrehmoment von bis zu 2.000 N.m. Kundenspezifische Konfigurationen für Schwermaschinenbau, Bergbau und Energiesektor sind verfügbar. Für Anfragen, kontaktieren Sie das SMI-Team →

---

Related Products — SMI Transmission & Drive Systems

• Agriculture Gearbox Design and Manufacturing — rotary mower gearbox series, custom configurations
• PTO Shaft and Power Take-Off Components — agricultural driveline supply to customer specification
• Contact SMI — Planetary Reducer Enquiry →

---

Request a Consultation

To discuss planetary reducer or gear component requirements, please provide the following at enquiry stage:

• Required gear ratio and number of stages
• Input speed — RPM
• Output torque requirement — N.m
• Output shaft configuration — square, hex, flange or custom
• Mounting geometry and envelope dimensions
• Material and heat treatment specification if known
• Annual volume — units per year
• Drawing or specification if available

SMI will respond with a written technical assessment and commercial proposal. Contact SMI — Planetary Reducer Enquiry →