EP-Auger Drive Feed Mixer Planetary Gearbox
Designed specifically for the demands of modern livestock feeding operations, the EP-Auger Drive feed mixer planetary gearbox is a fully modular auger drive system that handles mixer machines from small 4 m³ single-auger trailers right up to commercial 52 m³ multi-auger wagons. At its core, the unit combines a precision spiral bevel gear input stage — which accepts the tractor’s standard 540 rpm PTO shaft — with one or more planetary reduction stages that step speed down to the 20–35 rpm range required to drive mixing augers effectively through densely packed TMR rations of silage, hay, concentrates, and minerals.
What separates the EP-Auger Drive Feed Mixer Planetary Gearbox from fixed-design competitors is its modular build. The bevel input stage, the planetary body, and the output flange assembly each bolt together as discrete subassemblies, which means the same planetary core can be reconfigured with different bevel ratios, different output shaft interfaces, and different mounting flanges without replacing the entire unit.
1. Technical Parameters Of Feed Mixer Planetary Gearbox
| High Torque Feed Mixer Planetary Gearbox Model | Continuous Torque Nm | Max torque Nm | Input speed rpm | Ratio (Min-Max) i | Input Shaft |
| PGA-502 | 3810 | 7620 | 540 | 12.36-15.51 | 1"3/8 Z6 |
| PGA-1002/3 | 8500 | 17000 | 16.8-30.6 | 1"3/4 Z20 | |
| PGA-1202 | 11600 | 23200 | 11.1-19.4 | 1"3/4 Z20 | |
| PGA-1602/3 | 15700 | 31400 | 13.4-47.5 | 1"3/4 Z20 | |
| PGA-1702/3 | 15700 | 31400 | 13.4-47.5 | 1"3/4 Z20 | |
| PGA-2102/3 | 21000 | 47000 | 12.1-62.1 | 1"3/4 Z20 | |
| PGA-2502 | 23780 | 48000 | 13.6-23.6 | 1"3/4 Z20 | |
| PGA-3003/4 | 30760 | 61520 | 25.7-84.4 | 1"3/4 Z20 | |
| PGA-4203 | 42000 | 142000 | 27.8-91.4 | 1"3/4 Z20 |
| PAG Modular Auger Drives For Self-propelled Vertical Feed Mixers & Stationary Machine (Biogas) | |||
| Model | Continuous Torque Nm | Max torque Nm | Ratio (Min-Max) i |
| PGA-1603 | 15700 | 31400 | 24.4-116.9 |
| PGA-1703 | 15700 | 31400 | 24.4-116.9 |
| PGA-2103 | 21000 | 47000 | 31.8-126.5 |
| PGA-2503 | 23780 | 48000 | 35.7-142.2 |
| PGA-3004 | 30760 | 61520 | 97.4-612.3 |
| PGA-4204 | 42000 | 142000 | 105.4-662.8 |
2. Five Reasons Engineers Choose the EP-Feed Mixer Planetary Gearbox
01 — Dimensional Interchangeability with PGA Architecture
The EP-Auger Drive Feed Mixer Planetary Gearbox mirrors the PGA modular auger drive standard across output flange bolt circle, spline specification, and mounting interface, allowing field replacement of worn drives on PGA-compatible machines without any machining or fabrication. For farm workshops in Antioquia or Córdoba managing mixed-brand mixer fleets, this compatibility dramatically reduces the complexity of stocking and fitting replacement units and cuts downtime during the calving or peak feeding seasons when mixers run the hardest.
02 — Exceptional Torque Range Across the Model Line
From the compact single-stage unit rated at approximately 5,000 Nm continuous up to the heavy four-stage variant delivering 42,000 Nm, the EP-Auger Drive Feed Mixer Planetary Gearbox line covers every commercial mixer size with the right unit — not an oversized or undersized compromise. The peak torque capacity (start-up and shock events) reaches double the continuous rating on each frame, which provides the headroom necessary when a large silage bale is being cut at start-up and the auger momentarily stalls against dense, frozen material — a scenario that destroys undersized drives within a few seasons.
03 — Continuously Lubricated Upper Bearing
Upper bearing failure is the most frequent cause of premature auger drive retirement across the industry. The EP-Auger Drive Feed Mixer Planetary Gearbox addresses this directly through an integral oil channel system that delivers lubricant continuously to the upper bearing during operation, rather than relying on oil splash reaching an elevated bearing under the heavy radial and thrust loads the auger applies. This feature alone extends bearing service life significantly compared with designs that depend on oil splash lubrication at that location, and it eliminates a known failure mode without adding complexity or maintenance requirements.
04 — Optional Automatic Ratio-Change for Fuel Savings
An optional automatic load-sensing shift unit can be fitted that reads the mixer's weighing system output and shifts the drive between high-torque loading ratios and fast mixing ratios automatically, without any input from the tractor driver. This prevents drivetrain overloads during heavy loading phases and avoids wasted fuel running the auger faster than necessary during lighter mixing phases. Documented fuel savings of 25–30% per mixing cycle are consistently reported in field applications — meaningful economics for Colombian dairy operations running multiple mixing rounds daily across large herds.
05 — Field-Accessible Maintenance Without Removal
Oil drain and fill access points are positioned so that a routine oil change can be completed while the drive remains mounted on the machine — no unbolting, no hydraulic lift required. The magnetic drain plug is a standard fitting on all units; checking it at each service interval takes two minutes and provides an early warning of internal wear long before symptoms become audible. This practical attention to field serviceability matters enormously in Colombia's agricultural context, where machinery often operates far from specialist workshops and unplanned downtime during feeding schedules carries real welfare and productivity consequences for the herd.
3. Working Principle of the EP-Feed Mixer Planetary Gearbox
The EP-Auger Drive Feed Mixer Planetary Gearbox begins its power transmission at the bevel gear input module. A precision-ground spiral bevel pinion, mounted on the horizontal input shaft, meshes with a larger bevel ring gear on the vertical axis. This pair changes the direction of torque flow from horizontal (PTO shaft axis) to vertical (auger axis) while also contributing a first stage of speed reduction. The input shaft accepts a standard 1-3/4 inch 20-spline (Z20) interface at 540 rpm, or a 1-3/8 inch 6-spline version for smaller tractors, conforming to the ASABE S205 PTO interface standard used on every agricultural tractor sold in the Americas. The through-shaft design allows two bevel inputs — one on each side of the housing — making it practical to connect two PTO-driven feed mixer units from one tractor on machines with double-drive shaft inputs.
Below the bevel stage, the planetary reduction section takes over. The bevel output shaft drives a hardened sun gear at the centre of the first planetary stage. Three or more planet gears orbit the sun gear simultaneously, each one also engaging the internal ring gear teeth fixed in the housing. The planet carrier, which holds the planet gears on precision bearing pins, rotates at a speed determined by the ratio between the sun gear tooth count and the ring gear tooth count — typically reducing input speed by a factor of roughly five to eight in each stage. In a two-stage unit (the most common configuration for 8–16 m³ mixers), the first carrier's rotation feeds the second stage sun gear, compounding the reduction and delivering output speeds in the 33–35 rpm range at 540 rpm PTO input. In three-stage configurations for the largest machines, a third planet set is cascaded below the second, dropping output speed to the 17–22 rpm range appropriate for very large-volume mixers handling extremely dense rations.
On units fitted with the automatic ratio-change feature, the shift mechanism operates between two pre-selected ratios by altering the constraint conditions within the planetary assembly — either locking or freeing the ring gear of one stage, which changes the effective ratio without interrupting torque flow. The actuation signal comes from the mixer's weighing system ECU, and the shift itself completes in a fraction of a second, far faster than any manual gear change. This means the auger never stalls on heavy loads, and the tractor never needs to be throttled up aggressively to compensate — a combination that reduces mechanical stress throughout the entire driveline from auger tip to tractor crankshaft.
4. Materials & Build Construction
Feed mixer auger drives operate in one of the harshest duty cycles in agricultural machinery: high continuous torque, regular shock-load events during bale cutting, exposure to silage acids, crop dust, and outdoor humidity across multi-decade service lives that rarely include the kind of preventive maintenance a similar industrial machine would receive. The material specification of the EP-Auger Drive Feed Mixer Planetary Gearbox is a direct response to those conditions. The main housing is pressure-cast from FC-25 grey cast iron on standard frame sizes, a material chosen for its combination of structural stiffness, vibration damping, and machinability for the close-tolerance bearing bore finishes that precision gear alignment requires. On the heaviest-duty large-frame configurations, the housing transitions to nodular cast iron GGG-40, which adds the crack-arrest toughness margin needed when the auger strikes a buried stone or wire fragment in the silage — a real-world event that sends a single, very large shock load through the entire drive in milliseconds.
The bevel gear pair and all planetary gears are produced from 20CrMnT high-purity alloy steel, which undergoes carburising to a case depth of 0.8–1.2 mm, oil quenching, low-temperature tempering to relieve residual stress, and then finish-grinding of the tooth flanks. The resulting case hardness of HRC 58–62 resists the contact fatigue pitting that terminates gear life in lower-specification drives, while the HRC 32–38 core hardness preserves the fracture toughness that resists tooth bending fatigue under cyclic heavy loads. The output spindle is machined from 40Cr alloy steel, quench-and-tempered, and dimensioned to carry the combined axial load of the auger's self-weight and the radial loads from mixing forces — loads that are substantially higher and more directionally variable than in most other agricultural drive applications. Output shaft bearings are heavy-duty tapered roller units, specified for the combined radial and thrust loads with L10 service life calculations targeting 10,000 operating hours at the design load case. The labyrinth seal at the output shaft acts as the primary barrier against silage particles and moisture, with the oil-contact lip seal behind it providing the secondary seal — a two-stage arrangement that outlasts single-seal designs by a factor of two to three in service.
5. Where the EP-Auger Drive Feed Mixer Planetary Gearbox Is Used
The feed mixer planetary gearbox in the EP-Auger Drive Feed Mixer Planetary Gearbox series supports a broad spectrum of machine types and livestock sectors. Each application below represents a distinct use case with its own torque and speed requirements, and the modular nature of the drive allows each to be served from the same platform.
Single-Auger Trailed Vertical Mixers
The backbone of Colombia's small and mid-scale dairy sector, single-auger trailed vertical mixers in the 4–14 m³ range are driven by the EP-Auger Drive Feed Mixer Planetary Gearbox's small and mid-frame configurations. These machines follow the tractor around the feedlot, cutting and mixing silage bales, hay, concentrates, and liquid supplements in a single operation. The drive's compact mounting footprint allows the mixer body to remain at practical loading height while the gearbox sits low within the frame.
Double-Auger Trailed Vertical Mixers
Larger Colombian dairy and beef operations typically run double-auger trailed mixers in the 12–30 m³ range, feeding herds of 300–600 animals in a single batch. Double-auger machines place two planetary drives side by side, each driven from the same PTO shaft via a splitter box. The large and heavy-frame EP-Auger Drive Feed Mixer Planetary Gearbox units are sized for these loads, with the option to use different ratios on the two augers to create a counter-rotating mixing action that improves homogeneity of the finished ration.
Self-Propelled TMR Mixer Wagons
On the largest commercial dairy farms in Colombia's Sabana de Bogotá and the Valle del Cauca lowlands, self-propelled TMR mixer trucks replace tractor-drawn units for operational efficiency. These machines use the same EP-Auger Drive planetary module but with a hydraulic or electric motor input adapter in place of the PTO bevel stage, accepting continuous-duty cycles across multiple feeding rounds per day with no tractor availability dependency.
Stationary Feed Mixing Plants
Feed preparation facilities serving multiple farms or producing commercial balanced rations for sale use stationary mixer installations driven by electric motors through the EP-Auger Drive Feed Mixer Planetary Gearbox's electric motor input module. These setups run on 24-hour production cycles, far exceeding the intermittent-duty cycle of a tractor-PTO-driven trailer mixer, and the drive's oil-bath lubrication and robust bearing selection are engineered to sustain continuous-duty operation over multi-year service intervals between major overhauls.
Biogas Anaerobic Digester Agitators
Colombia's expanding biogas sector — particularly at large pig farms and dairy co-operatives in Nariño, Cundinamarca, and Antioquia — uses slow-speed, high-torque agitator drives to keep digester substrate uniformly mixed. The EP-Auger Drive Feed Mixer Planetary Gearbox's large-frame units at their lowest output speed ratios are well suited to digester service, where the drive runs at near-continuous duty for months between planned maintenance stops. The sealed housing and continuously lubricated upper bearing are particularly valued in the high-humidity, mildly corrosive atmosphere of a digester plant.
Replacement & Upgrade Drives
A considerable share of EP-Auger Drive Feed Mixer Planetary Gearbox deliveries to Colombia are vertical auger feed mixer gearbox Colombia replacement orders, where a worn OEM drive on an existing machine needs replacement. Because the EP-Auger Drive Feed Mixer Planetary Gearbox is dimensionally compatible with the PGA series architecture that equips a large fraction of the installed mixer fleet across Latin America, most replacements are drop-in installations. Upgrading to the optional automatic shift version during replacement is popular with farms seeking both the repair and the fuel-saving benefit in a single maintenance event.
6. Compliance, Standards & Regulations
Colombia — ICA, ICONTEC NTC Framework: Animal feeding equipment operating in Colombian livestock facilities falls within the regulatory scope of the Instituto Colombiano Agropecuario (ICA), which governs animal nutrition practices under Resolution 3183 and related instruments. While the ICA does not specify gearbox design standards directly, the mechanical reliability of feed mixer drive systems is integral to the consistency and hygiene of balanced ration production, particularly in facilities that supply commercial feed. The manufacturing quality baseline for the EP-Auger Drive Feed Mixer Planetary Gearbox — ISO 9001 certified production — satisfies the quality assurance expectations referenced in Colombian agricultural institutional procurement specifications. NTC (Normas Técnicas Colombianas) machinery safety standards administered by ICONTEC incorporate ISO machinery safety requirements by reference, and the drive's design is aligned with these.
European Union — Machinery Directive 2006/42/EC, EN ISO 4254-7: EN ISO 4254-7 specifically addresses safety requirements for feed mixers and related equipment, forming part of the implementation framework for the EU Machinery Directive 2006/42/EC. OEM mixer manufacturers exporting to EU markets, or Colombian buyers purchasing EU-origin mixer brands, should confirm that the replacement drive meets the mechanical strength, PTO guarding, and noise emission requirements of this standard. The EP-Auger Drive Feed Mixer Planetary Gearbox is designed to conform with these requirements, and a formal Declaration of Conformity can be provided on request for buyers who include CE documentation in their procurement specifications.
ASABE Standards — PTO Interface Conformance: The American Society of Agricultural and Biological Engineers standard ASABE S205 governs the 540 rpm Category 4 PTO interface (1-3/4 in. 20-spline), which the EP-Auger Drive Feed Mixer Planetary Gearbox input shaft conforms to. ASABE S207 covers the implement requirements of attachment to agricultural tractors. Both standards are recognised throughout the Americas, and compliance ensures the drive is mechanically compatible with any standard tractor sold in North or South America without the need for adapter couplings or custom input shaft machining.
ISO 6336 & AGMA 6123 — Gear Strength and Rating: Load capacity calculations for the EP-Auger Drive's gear sets are conducted against ISO 6336 (calculation of load capacity of spur and helical gears) and the AGMA 6123 design manual for enclosed epicyclic gear drives. These international standards are the accepted basis for independent verification of gear torque ratings and are routinely referenced by Colombian OEM engineering teams conducting formal drivetrain design reviews for new machine models.
RoHS & REACH — Material Compliance: All metallic components and lubricants supplied with the EP-Auger Drive Feed Mixer Planetary Gearbox conform with RoHS Directive 2011/65/EU and REACH Regulation (EC) No 1907/2006 on chemical substances, ensuring no restricted substances are present in the supply chain. Colombian agricultural machinery exporters to the EU or North American markets can include material compliance documentation for the EP-Auger Drive in their product technical files without additional testing.
7. About Us
We are a specialist feed mixer planetary gearbox manufacturer in Colombia and power transmission solutions with more than decades of focused experience in the design, production, and technical support of gear drive systems. Our product range spans precision servo-grade planetary gearboxes for automation and robotics through to heavy-duty mobile drive units for construction, mining, and agricultural equipment. The EP-Feed Mixer Planetary Gearbox is one of the flagship products in our industrial planetary gearbox line, backed by a manufacturing facility certified to ISO 9001 and equipped with CNC gear grinding, coordinate measuring machines, and full fatigue-test rigs. We supply directly to OEM machine builders, MRO distributors, and systems integrators across Latin America — including Colombia, Peru, Chile, and Brazil — as well as to customers in North America, Europe, and Southeast Asia.
Our engineering team is available to support gear selection, load calculations, motor compatibility checks, and dimensional drawings for any application. We maintain stock of the most popular EP-Feed Mixer Planetary Gearbox configurations for same-week dispatch, with full custom configurations available on lead times quoted at the time of order. If you are looking for a reliable right angle planetary gearbox supplier Colombia or need to source a right angle planetary gearbox replacement Colombia urgently, contact our technical sales team for a prompt response.
WorkShop
8. Complete Driveline — Related Products
The EP-Auger Drive planetary gearbox is one element of a full TMR mixer driveline. We also supply the PTO driveshafts and electric motors that connect to it, enabling buyers to source the complete power transmission assembly from a single supplier. A matched system reduces compatibility uncertainty, simplifies warranty management, and lets our engineering team support the entire driveline with a unified technical response. Below are the two complementary lines most frequently paired with the EP-Auger Drive Feed Mixer Planetary Gearbox.
Electric Motors
Frequently Asked Questions
Q1. What is the best feed mixer planetary gearbox for a cattle farm in Colombia running a 12 m³ double-auger TMR wagon with a 540 rpm PTO tractor?
For a 12 m³ double-auger machine at 540 rpm PTO, the EP-Auger Drive Feed Mixer Planetary Gearbox mid-frame configuration (PGA1202 equivalent) is the standard recommendation. It delivers 11,600 Nm continuous torque and 23,200 Nm peak, with an output speed of approximately 33.5 rpm — well matched to the auger speed requirements of a double-auger machine in that capacity range. Two units are required, one per auger. If silage bale cutting is a significant part of your daily mixing operation, adding the optional automatic ratio-change feature is worthwhile for drivetrain protection.
Q2. Is there a planetary gearbox for feed mixer for sale in Colombia that is suitable for both trailed mixer wagons and stationary biogas plant installations on the same farm?
Yes — the EP-Auger Drive's modular architecture allows the same planetary reduction body to be fitted with either a bevel PTO input module (for tractor-driven trailed mixers) or an electric motor input adapter (for stationary biogas agitator drives). This means a farm operating both a trailed TMR mixer and a biogas digester can standardise on the same planetary assembly across both applications, simplifying spares stocking. If both applications require the same reduction ratio, the planetary module itself is fully interchangeable between the two input configurations, enabling the workshop to maintain a smaller number of unique spare assemblies on site.
Q3. Which planetary gearbox for feed mixer is compatible with a Strautmann or Kuhn trailed vertical mixer already operating on a dairy farm in Colombia?
Many Strautmann, Kuhn, and other European-brand vertical mixer wagons use auger drives based on or dimensionally similar to the Comer Industries PGA architecture. The EP-Auger Drive Feed Mixer Planetary Gearbox is designed to be dimensionally interchangeable with PGA series units. To confirm compatibility for a specific Strautmann or Kuhn model, share the original drive model number or measure the output flange bolt circle and shaft spline specification and our team will confirm the correct EP-Auger Drive model before you commit to the purchase.
Q4. How does the TMR mixer planetary gearbox automatic shift feature work in practice, and is it worth the additional cost for a Colombian dairy operation?
The automatic shift reads a signal from the mixer's weighing system controller and selects the appropriate gear ratio — low speed / high torque during heavy loading, higher speed during mixing and unloading — without driver input. The shift is near-instantaneous and requires no interruption to PTO drive. In practical terms this means the tractor can run at a steady, efficient throttle setting throughout the mixing cycle, and the auger speed self-regulates to match the load. For a Colombian dairy running two or three mixing cycles daily, the documented 25–30% fuel saving typically makes the additional cost of the automatic shift option recoverable within two seasons.
Q5. What maintenance does an agricultural feed mixer gearbox in Bogotá require, and can a farm workshop handle service without specialist tools?
Routine maintenance consists of checking the magnetic drain plug for ferrous particles and performing an oil change at 500–1,000 operating hours using EP gear oil to ISO VG 220 specification. Both tasks require only standard hand tools and can be completed without removing the drive from the machine. Visual inspection of the input and output shaft seals for leaks should be part of each pre-season check. Full bearing replacement, if ever required due to a particle-contamination event or accidental overload, is a workshop task requiring a press and basic shaft pullers but is well within the capability of a competent farm mechanic.
Q6. When is it necessary to replace a feed mixer planetary gearbox rather than repair it, and what are the typical warning signs a Colombian farm mechanic should recognise?
Replacement is generally more cost-effective than repair when the unit shows: persistent gear noise that does not resolve after an oil change and filter clean, measurable gear backlash increase beyond the original specification, or repeated oil seal failure suggesting housing distortion or bearing journal wear. Oil with a greyish metallic appearance (aluminium particles from housing wear) or a magnetic drain plug with heavy ferrous deposits both indicate advanced internal wear. If a drive has experienced a sudden overload event — for example, from a wire or chain entering the auger — inspection for cracked housing, bent spindle, or spalled gear teeth is essential before returning the machine to service, and replacement is typically the right decision in that scenario.
Q7. How does the EP-Auger Drive Feed Mixer Planetary Gearbox compare in durability to the original Comer Industries PGA unit it replaces on a Colombian farm?
The EP-Auger Drive Feed Mixer Planetary Gearbox matches or exceeds the original PGA specification on all published performance parameters, and addresses one known weakness of the standard PGA design — upper bearing lubrication — through an integral oil channel that ensures continuous lubricant supply to the upper bearing under all operating orientations. Material specifications (20CrMnT gears, 40Cr spindle, tapered roller output bearings) are equivalent to or better than the original design, and manufacturing tolerances are held under ISO 9001 quality controls with documented process capability. Independent field validation has confirmed service life equivalent to OEM originals across multiple installation sites.
Editor: PXY
