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Draper Header

Product

Overview

A draper header is a wide combine header that moves cut crop on rubber belts instead of a cross auger. The belts, called drapers, carry the crop smoothly and gently along the header to the center, which gives a more even and less aggressive feed than an auger does. That even feed matters most on two fronts: very wide headers, where an auger struggles to move crop the long distance to the center without bunching, and easily shattered or tangled crops such as canola and pulses, where gentle handling cuts grain loss. The draper header trades the simplicity of an auger for smoother feeding and the ability to cut very wide.

Crop flows across the header on belts. A Flexible Cutterbar cuts the crop low, the Pickup Reel lays it onto a Side Draper belt on each side, those belts carry it inward to the Center Draper, and the center draper feeds it head-first into the combine. The Header Frame carries the wide span, the Driveline powers the knife mechanically and the belts hydraulically, the Combine Hookup latches it to the combine, and the Flex and Height Control hold the cutterbar at the right height and flex.

The flexible cutterbar

The Flexible Cutterbar cuts with a sickle the same way a grain platform does, with serrated Knife Section sections reciprocating against fixed Knife Guard guards, driven from both ends by Wobble Drive wobble boxes for an even stroke across a long bar. What sets a draper apart is that the bar can be made to flex: the Knife Bar is jointed and rides on a row of Flex Arm float arms, each held down by a Flex Spring at light pressure, so the bar bends along its length to hug rolling ground. This lets the header cut a low crop like soybeans right at the soil surface across an uneven field, picking up pods that a rigid bar would miss. Ground Skid skids carry the bar and set the base cut height. The same header can usually be locked rigid for standing cereals where flex is not needed.

The draper belts

The Side Draper belts replace the cross auger. Each is a wide, cleated Draper Belt running between a lagged Drive Roller and an Idler Roller, kept taut by Belt Tensioner tensioners and driven by its own Draper Motor hydraulic motor so its speed can be set independently. The belts carry the cut crop horizontally toward the center, laying it flat rather than rolling and dragging it the way an auger does, which is what makes the feed gentle. At the middle the Center Draper takes crop from both sides on a short Center Belt and a Feed Drum presses and feeds the merged mat into the combine feederhouse head-first and evenly. Because the operator can set side and center belt speeds, the header can be tuned to deliver a steady, well-formed feed in crops ranging from thin cereal to heavy, tangled canola.

Reel, frame, and stability

The Pickup Reel does the same job here as on any header, leaning the crop into the knife and sweeping it back, but on a draper it lays the crop neatly onto the belts rather than over an auger. Its cam-controlled Pickup Finger fingers and adjustable Reel Arm arms let the operator place the crop precisely on the drapers, which matters for clean feeding. Carrying all this across a span that can exceed fifteen metres demands a stiff Header Frame: a long Backframe, a Deck Frame supporting the belts, End Divider dividers parting the crop at the ends, and Stabilizer Wheel gauge wheels that steady the wide header and help it follow the ground without rocking.

Driveline, hookup, and control

The Driveline splits power by type of load. The knife, which needs steady mechanical drive, runs from a Knife Drive Gearbox through Wobble Drive boxes with a Slip Clutch for protection. The belts and reel, which benefit from fine speed control, run on hydraulic motors fed by a Hydraulic Pump and metered by a Flow Block, so each can be dialed in from the cab. The Combine Hookup latches the header to the combine with a Mount Frame, Latch latches, and a Multi-coupler and Drive Coupler that join drive and hydraulics in one motion. The Flex and Height Control are what make the flexing bar practical: Flex Sensor and Height Sensor sensors feed a Header Controller that holds each section of the cutterbar at a constant light ground pressure and runs the auto height, Tilt Cylinder tilt, and belt speeds together.

Use and comparison

In the field a draper header lets a combine cut a very wide swath while feeding gently and following the ground closely, which is why it has become the standard choice for large-acre cereal and oilseed farms and for soybean growers who need a low, flexing cut. Compared with a Combine Grain Header auger platform, the draper feeds more smoothly and cuts wider but costs more and has more belts and hydraulic motors to maintain. Compared with a Combine Corn Head, it is a general crop header rather than a row-crop tool, cutting whole plants rather than snapping ears. The draper earns its place where width, gentle handling, and close ground following all matter at once, taking full advantage of a high-capacity combine across a wide range of crops.

Draper Header parts and their functions

8 top-level parts · 557 parts in total · full bill of materials below
Draper Header parts diagram: 1 flexible cutterbar, 2 side draper, 3 center draper, 4 pickup reel, 5 header frame, 6 driveline, 7 combine hookup, 8 flex and height control. 557 parts in 8 assemblies.
Draper Header parts diagram. Numbers match the table below; each box is one top-level part or assembly with what it contains.
#PartQtyWhat it does
1 Flexible Cutterbar 7 parts Flexible sickle cutterbar
2 Side Draper 6 parts Side draper belts
3 Center Draper 5 parts Center feed draper
4 Pickup Reel 7 parts Pickup reel
5 Header Frame 5 parts Header frame
6 Driveline 5 parts Driveline
7 Combine Hookup 6 parts Combine hookup
8 Flex and Height Control 5 parts Flex and height control

3D model

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Build & assembly graph

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Bill of materials for Draper Header

8 top-level lines · 65 rows shown · 557 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Flexible Cutterbar 7 parts draper-header-cutterbar 1 215 assembly
1.1 Knife Bar draper-header-knife-bar 1 · part
1.2 Knife Section draper-header-knife-section 90× 90 · part
1.3 Knife Guard draper-header-guard 90× 90 · part
1.4 Flex Arm draper-header-flex-arm 12× 12 · part
1.5 Flex Spring draper-header-flex-spring 12× 12 · part
1.6 Wobble Drive draper-header-wobble-drive 2 · part
1.7 Ground Skid draper-header-skid 8 · part
2 Side Draper 6 parts draper-header-side-draper 2 10 assembly
2.1 Draper Belt draper-header-draper-belt 2 · part
2.2 Drive Roller draper-header-drive-roller 2 · part
2.3 Idler Roller draper-header-idler-roller 2 · part
2.4 Belt Tensioner draper-header-belt-tensioner 4 · part
2.5 Draper Motor draper-header-draper-motor 2 · part
2.6 Ball Bearing ball-bearing 8 · part
3 Center Draper 5 parts draper-header-center-draper 1 9 assembly
3.1 Center Belt draper-header-center-belt 1 · part
3.2 Center Roller draper-header-center-roller 2 · part
3.3 Feed Drum draper-header-feed-drum 1 · part
3.4 Draper Motor draper-header-draper-motor 1 · part
3.5 Ball Bearing ball-bearing 4 · part
4 Pickup Reel 7 parts draper-header-reel 1 157 assembly
4.1 Reel Shaft draper-header-reel-shaft 1 · part
4.2 Reel Bat draper-header-reel-bat 6 · part
4.3 Pickup Finger draper-header-reel-finger 140× 140 · part
4.4 Finger Cam draper-header-reel-cam 2 · part
4.5 Reel Arm draper-header-reel-arm 3 · part
4.6 Reel Motor draper-header-reel-motor 1 · part
4.7 Ball Bearing ball-bearing 4 · part
5 Header Frame 5 parts draper-header-frame 1 13 assembly
5.1 Backframe draper-header-backframe 1 · part
5.2 End Divider draper-header-end-divider 2 · part
5.3 Deck Frame draper-header-deck-frame 1 · part
5.4 Stabilizer Wheel 3 parts draper-header-stabilizer-wheel 2 4 assembly
5.4.1 Wheel Rim draper-header-wheel-rim 2 · part
5.4.2 Tire draper-header-wheel-tire 2 · part
5.4.3 Ball Bearing ball-bearing 4 · part
5.5 Fastener Set fastener-set 1 · part
6 Driveline 5 parts draper-header-driveline 1 13 assembly
6.1 Knife Drive Gearbox 4 parts draper-header-input-gearbox 1 9 assembly
6.1.1 Helical Gear Pair gear-pair 2 · part
6.1.2 Gearbox Housing gearbox-housing 1 · part
6.1.3 Ball Bearing ball-bearing 4 · part
6.1.4 Oil Seal oil-seal 2 · part
6.2 Hydraulic Pump draper-header-hydraulic-pump 1 · part
6.3 Flow Block draper-header-flow-block 1 · part
6.4 Hose Set draper-header-hose-set 1 · part
6.5 Slip Clutch draper-header-slip-clutch 1 · part
7 Combine Hookup 6 parts draper-header-hookup 1 14 assembly
7.1 Mount Frame draper-header-mount-frame 1 · part
7.2 Latch draper-header-latch 2 · part
7.3 Multi-coupler draper-header-multi-coupler 1 · part
7.4 Drive Coupler draper-header-drive-coupler 1 · part
7.5 Wire Bundle wire-bundle 1 · part
7.6 Connector connector 8 · part
8 Flex and Height Control 5 parts draper-header-controls 1 116 assembly
8.1 Flex Sensor draper-header-flex-sensor 6 · part
8.2 Height Sensor draper-header-height-sensor 4 · part
8.3 Header Controller 4 parts draper-header-control-ecu 1 103 assembly
8.3.1 Bare PCB pcb-bare 1 · part
8.3.2 Microcontroller mcu 1 · part
8.3.3 CAN Interface draper-header-can-iface 1 · part
8.3.4 SMD Passive (R/C/L) smd-passives 100× 100 · part
8.4 Pressure Sensor pressure-sensor 1 · part
8.5 Tilt Cylinder draper-header-tilt-cylinder 2 · part

Sourcing: possible vendors

Prices, MOQ, and lead times are algorithmic estimates, not quotes, and not claims about these companies. Company mappings are curated by keyword; est. price band $5k–$800k. How estimates work
VendorHQSpecialtyMOQLead time
🇺🇸John Deere
deere.com ↗
Moline, US Agriculture & turf made to order 14–24 wks
cnh.com ↗ Basildon, GB Agriculture (Case IH, New Holland) made to order 14–24 wks
🇺🇸AGCO
agcocorp.com ↗
Duluth, US Agriculture (Fendt, Massey Ferguson) made to order 14–24 wks
🇩🇪Claas
claas.com ↗
Harsewinkel, DE Harvesters & tractors made to order 14–24 wks
🇯🇵Kubota
kubota.com ↗
Osaka, JP Compact tractors & equipment made to order 14–24 wks

980-word article