{"id":1418,"date":"2026-06-24T06:23:52","date_gmt":"2026-06-24T06:23:52","guid":{"rendered":"https:\/\/pto-gearbox.net\/?p=1418"},"modified":"2026-06-24T06:23:52","modified_gmt":"2026-06-24T06:23:52","slug":"hay-tedder-gearbox-multi-rotor-pto-drive-for-fast-crop-drying","status":"publish","type":"post","link":"https:\/\/pto-gearbox.net\/da\/hay-tedder-gearbox-multi-rotor-pto-drive-for-fast-crop-drying\/","title":{"rendered":"Gearkasse til h\u00f8vender \u2014 Multi-rotor PTO-drev til hurtig afgr\u00f8det\u00f8rring"},"content":{"rendered":"
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<\/div>\n
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Gearkasse til h\u00f8vender \u2014 Multi-rotor PTO-drev til hurtig afgr\u00f8det\u00f8rring<\/h1>\n

Central distribution and individual rotor gearboxes for 2 to 8+ rotor hay tedders \u2014 delivering the high-speed tine arm rotation, multi-output synchronisation, and lightweight durability that efficient crop aeration demands.<\/p>\n

Anmod om specifikationer<\/a><\/p>\n<\/div>\n<\/div>\n

\n

<\/p>\n

\n
\n
1:1 \u2013 1:1,5<\/div>\n
Central Gearbox Ratio<\/div>\n<\/div>\n
\n
15 \u2013 50+ HP<\/div>\n
PTO-effektomr\u00e5de<\/div>\n<\/div>\n
\n
400 \u2013 600<\/div>\n
Rotoromdrejninger<\/div>\n<\/div>\n
\n
4 \u2013 12+ m<\/div>\n
Arbejdsbredde<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

What Is a Hay Tedder Gearbox?<\/h2>\n

EN gearkasse til h\u00f8vender<\/strong> is the central distribution gear unit \u2014 plus the individual rotor drive gearboxes \u2014 that power the spinning tine rotors on a hay tedder. After a mower cuts the standing grass or legume crop and leaves it lying in swaths, the tedder passes over the field and lifts the cut material into the air with spring-loaded tines mounted on rotating arms, scattering it loosely and evenly across the full working width. This thorough aeration dramatically accelerates drying \u2014 reducing the time from mowing to baling by 30 to 50 percent in typical conditions \u2014 and achieving uniform moisture content across the windrow that produces consistent bale quality and minimises the risk of mould development in stored hay or silage.<\/p>\n

De gearkasse til h\u00f8vender<\/strong> system must distribute PTO power from a single input to 2, 4, 6, or 8+ individual rotors spread across working widths of 4 to 12+ metres. Each rotor carries 4 to 8 tine arms rotating at 400 to 600 RPM \u2014 fast enough to lift and throw the crop material 1 to 3 metres into the air. The central gearbox receives the 540 RPM PTO input and distributes it through driveshafts to each rotary tedder gearbox<\/strong> at each rotor position. The engineering challenge is maintaining equal speed at every rotor across the full width while the machine flexes and articulates over uneven ground \u2014 because speed variation between rotors produces uneven crop distribution that creates wet spots in the field, reducing the overall drying rate.<\/p>\n

<\/p>\n

How the Tedder Drive System Works<\/h2>\n
\n
\n

Traktoren PTO<\/a> drives the central gearkasse til h\u00f8vender<\/strong> at 540 RPM. This central unit \u2014 typically a multi-output right-angle bevel or spur gear distribution box \u2014 splits the power into two or more output shafts, each feeding a driveline that runs to a rotor gearbox at each rotor position. On a 4-rotor tedder, the central gearbox has two outputs (left and right), each driving a secondary cross-shaft that powers two rotors. On larger 6 to 8 rotor machines, cascading gearbox arrangements pass power from rotor to rotor across the full working width.<\/p>\n

Each individual tedder rotor gearbox<\/strong> is a compact right-angle bevel unit that redirects the horizontal driveshaft rotation to vertical output, spinning the tine arm assembly at 400 to 600 RPM. The 1:1 ratio is most common (output speed equals input speed), though some designs use 1:1.2 to 1:1.5 speed reduction for wider rotors that need higher torque and lower tip speed. The rotor gearbox must be lightweight (2 to 5 kg) because it is mounted on the rotor frame that follows the ground contour on individual castor wheels \u2014 excess weight reduces the ground-following responsiveness and increases tyre wear.<\/p>\n<\/div>\n

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\"Hay<\/div>\n

Hay tedder gearbox \u2014 compact right-angle bevel drive for high-speed tine rotor applications<\/p>\n<\/div>\n<\/div>\n

<\/p>\n

Tedder Size and Gearbox Configuration<\/h2>\n
\n\n\n\n\n\n\n\n\n
Tedder Size<\/th>\nRotors<\/th>\nArbejdsbredde<\/th>\nPTO-kraft<\/th>\nTotal Gearboxes<\/th>\n<\/tr>\n<\/thead>\n
Compact<\/td>\n2<\/td>\n4 \u2013 5 m<\/td>\n15 \u2013 25 HK<\/td>\n3 (1 central + 2 rotor)<\/td>\n<\/tr>\n
Mid-Size<\/td>\n4<\/td>\n6 \u2013 8 m<\/td>\n25 \u2013 35 HP<\/td>\n5 (1 central + 4 rotor)<\/td>\n<\/tr>\n
Large<\/td>\n6<\/td>\n8 \u2013 10 m<\/td>\n30 \u2013 40 HP<\/td>\n7 (1 central + 6 rotor)<\/td>\n<\/tr>\n
Extra-Large<\/td>\n8+<\/td>\n10 \u2013 12+ m<\/td>\n35 \u2013 50+ HP<\/td>\n9+ (1 central + 8+ rotor)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

<\/p>\n

High-Speed Bearing Design for Tine Arm Rotation<\/h2>\n

Each tedder rotor gearbox<\/strong> output shaft operates at 400 to 600 RPM while carrying the centrifugal loads from 4 to 8 tine arms extending 0.6 to 1.0 metre from the rotor centre. At 500 RPM with 8 tine arms, the combined centrifugal force generated by the rotating tine mass produces a continuous radial load on the output bearing that is several times the static weight of the tine assembly. This centrifugal loading is the dominant force on the hay tedder gearbox bearing<\/strong> \u2014 not the torque from turning the tines through the crop (which is relatively light, as tedding requires only lifting and scattering loose cut material, not cutting or pulling).<\/p>\n

Sealed deep-groove ball bearings with C3 internal clearance are the standard choice for tedder rotor gearbox output positions. The C3 clearance accommodates the centrifugal expansion of the inner ring at operating speed and the thermal expansion from the sustained high-speed rotation. Bearing seals must exclude the hay dust, soil particles, and moisture from dew-laden crop that the rotor tines throw in every direction during operation \u2014 making sealed-for-life bearings (no field re-greasing) the preferred configuration for the rotor gearbox positions where access is limited and maintenance is impractical during the time-sensitive haymaking window.<\/p>\n

<\/p>\n

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Speed Uniformity across All Rotors<\/div>\n

All rotors across the tedder width must operate at the same speed to produce uniform crop distribution. If one rotor runs 5 percent slower than its neighbours (from a worn gearbox, loose driveshaft coupling, or low oil level), that rotor leaves a denser crop layer at its position \u2014 creating a wet strip that dries more slowly than the surrounding area. On a 6-rotor tedder, a single underperforming rotor can delay the entire field from reaching target moisture content, extending the drying period and increasing weather-damage risk for the complete crop.<\/p>\n<\/div>\n

<\/p>\n

Ground-Following Articulation and Driveline Flexibility<\/h2>\n

Each tedder rotor is mounted on an independent frame section that follows the ground contour on its own castor wheel. On undulating terrain, adjacent rotors may operate at different heights \u2014 one on a hilltop, the next in a hollow \u2014 with vertical offsets of 200 to 500 mm between neighbouring rotor positions. The driveshafts<\/a> connecting the rotors must accommodate this continuous angular variation through U-joints or constant-velocity joints while maintaining constant speed transmission to every gearkasse til h\u00f8vender<\/strong> at every rotor position.<\/p>\n

Telescoping driveshafts between rotor gearboxes allow the effective shaft length to change as the machine articulates over ground contours. The telescoping joint must slide freely under the combined torque and angular misalignment conditions \u2014 if it binds (from corrosion, lack of grease, or debris contamination), the locked shaft forces the rotor frame to follow the adjacent frame rather than the ground contour, lifting the tines above the crop layer at one position and pushing them into the soil at another. This produces both ineffective tedding (missed crop) and accelerated tine and gearbox wear from sustained soil contact.<\/p>\n

U-joint and telescoping-shaft greasing every 8 to 10 operating hours is essential for maintaining the tedder gearbox<\/a> ground-following capability that uniform crop aeration requires. When inspecting the driveshaft joints during greasing, also check each U-joint for play \u2014 more than 0.5 mm of perceptible free play indicates developing joint wear that will produce speed pulsation at the affected rotor, degrading the tedding uniformity at that position before the joint fails completely.<\/p>\n

\"Agricultural<\/div>\n

<\/p>\n

Folding Transport and Driveline Disconnection<\/h2>\n

Large tedders (6 to 8+ rotors) fold hydraulically for transport \u2014 reducing the working width from 8 to 12+ metres to a road-legal 2.5 to 3.0 metre transport width. The folding action requires the inter-rotor driveshafts to disconnect and reconnect as the outer rotor sections fold upward. Most designs use clutch couplings or dog-tooth engagement mechanisms at the fold joints that automatically disconnect the driveline when the section folds and re-engage when it unfolds \u2014 eliminating the need for the operator to manually connect or disconnect driveshafts during the folding sequence.<\/p>\n

The automatic driveline disconnection mechanism must engage positively under the full torque of the operating tedder \u2014 if it slips or fails to fully engage, the affected rotor section either runs at reduced speed (partial engagement) or does not run at all (failed engagement), both of which the operator may not notice from the tractor seat. Pre-season verification of the engagement mechanism at every fold joint \u2014 checking for full tooth meshing, proper spring tension, and absence of wear or corrosion on the engagement surfaces \u2014 is essential for ensuring that all rotor sections receive full drive when unfolded for operation. Worn engagement teeth produce an intermittent grinding noise during the first few seconds after unfolding \u2014 this noise is the warning signal that the coupling needs replacement before it fails completely in the field.<\/p>\n

During transport, the folded gearkasse til h\u00f8vender<\/strong> units at the outer rotor positions are exposed to road vibration and spray from the tractor wheels. Protective covers over the gearbox housings prevent road grit and water from contaminating the seals and shaft surfaces during transport \u2014 a precaution that is particularly important for tedders that travel significant distances between fields on public roads where road salt (in regions that salt winter roads) can accelerate seal and fastener corrosion.<\/p>\n

Tekniske specifikationer p\u00e5 et \u00f8jeblik<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Specifikation<\/th>\nV\u00e6rdi \/ Interval<\/th>\n<\/tr>\n<\/thead>\n
Indgangshastighed<\/td>\n540 omdr.\/min. (standard PTO)<\/td>\n<\/tr>\n
Rotorhastighed<\/td>\n400 \u2013 600 omdr.\/min.<\/td>\n<\/tr>\n
Central Gearbox Ratio<\/td>\n1:1 to 1:1.5 (multi-output distribution)<\/td>\n<\/tr>\n
Rotor Gearbox Ratio<\/td>\n1:1 (most common)<\/td>\n<\/tr>\n
Effektvurdering<\/td>\n15 \u2013 50+ HP total system<\/td>\n<\/tr>\n
Geartype<\/td>\nSpiral bevel (case-carburised)<\/td>\n<\/tr>\n
Gearmodul<\/td>\n3 \u2013 5 mm<\/td>\n<\/tr>\n
Overfladeh\u00e5rdhed<\/td>\n58 \u2013 62 timers hastighed<\/td>\n<\/tr>\n
Udgangslejer<\/td>\nSealed deep-groove ball C3 (centrifugal-load rated)<\/td>\n<\/tr>\n
Oliespecifikation<\/td>\nEP gearolie SAE 80W-90 (ISO VG 220)<\/td>\n<\/tr>\n
Oil Volume (per rotor unit)<\/td>\n0.15 \u2013 0.4 litres<\/td>\n<\/tr>\n
Rotor Gearbox Weight<\/td>\n2 \u2013 5 kg per rotor unit<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

<\/p>\n

Hay Tedder Gearbox Oil and Lubrication<\/h2>\n

EP gear oil SAE 80W-90 (ISO VG 220 equivalent) is the standard hay tedder gearbox oil<\/strong> for both the central distribution unit and the individual rotor gearboxes. The power per rotor is modest (3 to 8 HP per rotor on a 6-rotor machine) and operating temperatures remain moderate (45 to 65 degrees Celsius), so the thermal demands do not require synthetic oil \u2014 though synthetic VG 220 provides benefit for operations that ted in early morning when dew-laden crop creates a cold, wet environment and the gearbox must start at low ambient temperatures. The very small oil volume per rotor gearbox (0.15 to 0.4 litres) means that even a minor leak or seal failure can empty the gearbox within a few operating hours \u2014 making pre-season oil level verification at every rotor position a critical maintenance action.<\/p>\n

Oil change intervals follow the standard 500-hour or annual schedule. For the central landbrugsgearkasse<\/a>, which handles the full system power, synthetic VG 220 with a 500-hour interval provides adequate protection. For the individual rotor gearboxes, the modest power level and intermittent duty pattern (tedding is typically 2 to 6 hours per cutting cycle, with multiple cycles per season totalling 50 to 200 hours annually) mean that annual pre-season oil change is usually the binding maintenance interval rather than the hour-based limit.<\/p>\n

<\/p>\n

\n
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Central Distribution Gearbox<\/div>\n

Multi-output right-angle bevel. Handles full system power (15 to 50+ HP). Larger housing, higher oil volume (0.5 to 1.5 litres). Mounted on the main tedder frame. Standard agricultural gearbox maintenance schedule applies.<\/p>\n<\/div>\n

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Individual Rotor Gearbox<\/div>\n

Compact single-output right-angle bevel. Low power per unit (3 to 8 HP). Lightweight (2 to 5 kg) for ground following. Tiny oil volume (0.15 to 0.4 litres). Sealed bearings \u2014 no field re-greasing. Critical: check oil level at every unit before tedding.<\/p>\n<\/div>\n<\/div>\n

\"PTO<\/div>\n

<\/p>\n

S\u00e6sonbestemt vedligeholdelsesplan<\/h2>\n
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Pre-Season (All Rotors)<\/div>\n

Oil change at central gearbox and every rotor unit. Rotate each rotor by hand to verify smooth bearing action. Inspect driveshaft U-joints and telescoping tubes \u2014 grease all fittings. Check tine arms and spring tine condition. Verify all rotor gearbox drain plugs are tight. Run the tedder unloaded for 5 minutes at operating speed, listening for bearing noise at each rotor.<\/p>\n<\/div>\n

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Every 8 \u2013 10 Hours<\/div>\n

Grease all driveshaft U-joints and telescoping spline tubes. Visual check for oil leaks at every rotor gearbox. Inspect tine arms for bent or missing tines (imbalanced rotors increase bearing vibration). Clear accumulated hay from around gearbox seals and driveshaft joints.<\/p>\n<\/div>\n

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Opbevaring efter s\u00e6sonen<\/div>\n

Clean all hay debris from every rotor, gearbox, and driveshaft. Top up oil at every rotor unit and central gearbox. Apply grease to exposed shaft surfaces and driveshaft joints. Store under cover (UV exposure degrades housing paint and seal materials). Record any rotors with noise, temperature change, or vibration for priority pre-season repair or replacement before the next cutting cycle.<\/p>\n<\/div>\n<\/div>\n

<\/p>\n

Aftermarket Hay Tedder Gearbox Replacement<\/h2>\n

Hay tedder gearbox replacement<\/strong> is driven primarily by output bearing fatigue from the sustained centrifugal loading of the spinning tine arms and by seal degradation from the hay dust and moisture environment. A well-maintained rotor gearbox typically lasts 8 to 15 years (800 to 2,000 operating hours). When replacing gearboxes on a multi-rotor tedder gearbox<\/strong> system, replace all rotor units from the same production batch to maintain speed uniformity across the working width \u2014 mixing new and worn gearboxes with different friction characteristics produces the rotor speed variation that creates uneven crop distribution.<\/p>\n

Cross-reference parameters include the input shaft configuration, output shaft size and coupling type, housing mounting bolt pattern, bevel ratio, and weight (critical for ground-following performance). Our engineering team maintains cross-reference data for major tedder brands and can supply aftermarket replacements with verified dimensional compatibility. Volume pricing for complete rotor sets (2 to 8+ units per set) ensures cost-effective matched-batch replacement for the entire tedder width, ensuring uniform performance from the first cut to the last.<\/p>\n

\"Typer<\/div>\n

<\/p>\n

Ofte stillede sp\u00f8rgsm\u00e5l<\/h2>\n
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\nWhat ratio does a hay tedder gearbox use?+<\/span><\/summary>\n
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1:1 is most common at both the central distribution gearbox and individual rotor gearboxes \u2014 the 540 RPM PTO input passes through to the rotors without speed change. Some designs use 1:1.2 to 1:1.5 at the central unit for slight speed reduction, producing rotor speeds of 360 to 450 RPM for wider rotors or heavier crop conditions.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

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\nHow many gearboxes does a hay tedder need?+<\/span><\/summary>\n
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One central distribution gearbox plus one rotor gearbox per rotor. A 4-rotor tedder needs 5 gearboxes total; a 6-rotor needs 7; an 8-rotor needs 9. All rotor gearboxes should be identical specification and ideally from the same production batch for uniform speed across the working width.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

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\nWhy does rotor speed uniformity matter?+<\/span><\/summary>\n
\n

A rotor running 5 percent slower than its neighbours leaves a denser crop layer at that position \u2014 creating a wet strip that dries more slowly. On a 6-rotor tedder, a single underperforming rotor can delay the entire field from reaching target moisture, extending drying time and increasing weather-damage risk. Replace all rotor gearboxes as a matched set to maintain uniformity.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

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\nWhat oil should I use in tedder gearboxes?+<\/span><\/summary>\n
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EP gear oil SAE 80W-90 (ISO VG 220) for both central and rotor gearboxes. Synthetic optional but beneficial for cold early-morning tedding. Oil volume per rotor: 0.15 to 0.4 litres \u2014 check every unit before each tedding session because even a minor leak can empty the gearbox within hours. Annual oil change at all positions.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

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\nWhy is the rotor gearbox so lightweight?+<\/span><\/summary>\n
\n

Each rotor frame follows the ground contour independently on a castor wheel. A heavy gearbox (above 5 to 6 kg) reduces ground-following responsiveness \u2014 the inertia delays the frame from rising over bumps and dropping into hollows, causing the tines to miss crop in depressions and contact soil on high spots. Lightweight aluminium or thin-wall cast iron housings with compact gear sets keep rotor gearbox weight at 2 to 5 kg.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

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\nHow long do hay tedder gearboxes last?+<\/span><\/summary>\n
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8 to 15 years (800 to 2,000 operating hours) with proper maintenance. The primary life limiter is output bearing fatigue from centrifugal tine-arm loading and seal degradation from hay dust and moisture. Annual oil changes, driveshaft greasing, and pre-season bearing inspection are the most effective and cost-efficient life-extension measures available.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

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\nDo you supply hay tedder gearboxes?+<\/span><\/summary>\n
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Yes \u2014 we manufacture both central distribution gearboxes and individual rotor gearboxes for 2 to 8+ rotor hay tedders. All units feature case-carburised spiral bevel gears, sealed C3-clearance output bearings, and lightweight housing designs for optimal ground-following responsiveness. Volume pricing for complete rotor sets from matched production batches. Contact our team with your tedder model, rotor count, and working-width specification for precise matching and competitive volume pricing.<\/p>\n<\/div>\n<\/details>\n<\/div>\n

<\/p>\n

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Ted Faster, Dry Sooner<\/h2>\n

From compact 2-rotor units to wide 8+ rotor systems \u2014 our hay tedder gearboxes deliver the lightweight precision, synchronised speed, and multi-season bearing life that efficient crop aeration demands.<\/p>\n

Kontakt vores ingeni\u00f8rer<\/a><\/p>\n<\/div>\n

Redakt\u00f8r: Cxm<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"

Hay Tedder Gearbox \u2014 Multi-Rotor PTO Drive for Fast Crop Drying Central distribution and individual rotor gearboxes for 2 to 8+ rotor hay tedders \u2014 delivering the high-speed tine arm rotation, multi-output synchronisation, and lightweight durability that efficient crop aeration demands. Request Specifications 1:1 \u2013 1:1.5 Central Gearbox Ratio 15 \u2013 50+ HP PTO Power […]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[4042],"tags":[],"class_list":["post-1418","post","type-post","status-publish","format-standard","hentry","category-agricultural-gearbox"],"_links":{"self":[{"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/posts\/1418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/comments?post=1418"}],"version-history":[{"count":1,"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/posts\/1418\/revisions"}],"predecessor-version":[{"id":1420,"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/posts\/1418\/revisions\/1420"}],"wp:attachment":[{"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/media?parent=1418"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/categories?post=1418"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pto-gearbox.net\/da\/wp-json\/wp\/v2\/tags?post=1418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}