DJI Agras T40 OEM Centrifugal Sprinkler Spinner Disk (Upper & Lower Selection)

OEM Centrifugal Sprinkler Spinner Disk | Original DJI Agras T40 Upper & Lower Spinner Disk Selection | Precision Atomization Component | Spray System Repair Part | Field-Ready Original Replacement Part

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🇺🇸 U.S.A. FIRST

Ares Acres LLC is a U.S.-based authorized DJI Agras reseller supporting American agricultural drone operators with genuine DJI Agras OEM replacement parts, accessories, and field-ready inventory.

FREE & FAST Shipping is included for all U.S. customers.

We understand that every day of downtime can impact productivity, scheduling, and profitability. That's why we focus on providing fast fulfillment, responsive customer support, and reliable access to the parts operators need most.

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✅ DJI Agras T40 Compatibility Guarantee

• 🇺🇸 USA Compatibility Guarantee
• 👍🏻 Satisfaction Guarantee
• 💵 Money Back Guarantee
• 📦 Same Day Shipping & Tracking

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📦 Package Includes

• 1 × DJI Original Centrifugal Sprinkler Spinner Disk (choose Upper or Lower)
• Factory-sealed protective packaging
• Quick installation reference

⚠️ Please note: This listing is for one spinner disk only. Select the Upper or Lower position that matches your repair. If both disks show wear, order one of each to service the complete sprinkler.

SKU Options:

• AG-SPRDISK-UP-000901 → DJI Agras T40 Upper Centrifugal Sprinkler Spinner Disk
• AG-SPRDISK-LOW-000902 → DJI Agras T40 Lower Centrifugal Sprinkler Spinner Disk

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🔧 Component Overview

The DJI Agras T40 Centrifugal Sprinkler Spinner Disk is the official OEM replacement for the upper or lower rotating disk that drives uniform chemical and fertilizer dispersion.

These precision-balanced components maintain consistent droplet size and spray distribution, critical for high-volume agricultural applications.

When a spinner disk is worn or damaged, spray patterns can become inconsistent, reducing coverage and wasting product. Replacing only the upper or lower disk with this genuine DJI part restores full spraying performance and minimizes downtime.

Key features include:

• Genuine DJI OEM part – factory-certified for Agras T40 drones
• Position-specific options – Upper or Lower centrifugal spinner disk
• Optimized atomization – maintains consistent droplet size for uniform coverage
• Durable construction – resistant to chemicals, corrosion, and heavy-duty field conditions
• Cost-effective repair – replace a single disk instead of the full sprinkler assembly

Spinner disks live in the most demanding zone of the spray system—spinning at high speed in constant chemical contact. During commercial use, they may be exposed to:

• Continuous high-RPM rotation
• Constant chemical contact
• Herbicide, fungicide, and insecticide formulations
• Liquid fertilizer exposure
• Abrasive particles and sediment
• Flight vibration
• Repeated cleaning cycles
• UV exposure
• Temperature changes
• High-hour daily deployment

Over time, these conditions gradually erode the disk's precision surfaces—and because atomization quality degrades slowly, many operators don't notice until coverage problems show up in the crop.

Prove the pattern is wrong before you buy a disk. Lay a line of water-sensitive cards, or plain cardboard if that is what you have, on the ground across the swath, run the system on clean water at your normal rate, and fly or hover a controlled pass over them. Then compare the cards under each sprinkler position on the same aircraft. Every head producing the same imperfect deposit is a rate, height, or speed problem you can fix from the controller. One head laying down a deposit unlike its neighbors is that head, and on a centrifugal sprinkler the disk is the part in it that changes with wear.

Do a spin-down check with the aircraft powered off and the props secured. Turn each sprinkler head over by hand and watch the disk edge against a fixed reference such as the housing lip or a straight tool laid alongside. A sound assembly turns true and coasts to a stop quietly. A disk that is chipped, warped, or sitting up on trapped residue traces a visible wobble as it turns, and a disk that is rubbing its housing or the opposite disk gives a light, repeating scrape you can hear in a quiet shop long before it shows up in the crop.

Run a fingernail outward across the throwing surfaces and off the edge, then do exactly the same on the unused replacement and compare what you feel. Erosion on a spinner disk is not even: the faces that meet the liquid first go first, so the wear you are hunting is a feathered, serrated, or stepped edge where the surface used to run out smooth. This is the single most useful bench check on the part, because a disk can look perfectly serviceable from two feet away and still have lost the edge geometry that sets droplet size.

Separate an atomization fault from a flow fault by measuring, not by looking. With clean water in the tank, catch the output of each sprinkler in a graduated container for the same fixed count of seconds and write the numbers down. Even output across all heads with a poor pattern at one of them puts the fault at the atomizer, which is the disk. Output that is visibly down at one head points upstream instead, to a blocked filter, a kinked or collapsing hose, a tired pump, or a valve that is not opening fully, and no disk will fix any of those.

Take the stack apart before you decide a disk is clean. The faces that matter most are the ones you cannot see with the sprinkler assembled: the underside of the upper disk, the top of the lower disk, and the area around the hub where the two run closest together. Dried chemical builds there first because it is the part nobody rinses properly, and a deposit in that gap changes both the mass balance of the rotating assembly and the way liquid is fed outward. A disk that looks spotless from above is regularly the one carrying a crust underneath.

If the app is reporting a sprinkler or motor fault, treat the disk as a suspect rather than dismissing it as electronics. A disk that has gone out of balance, picked up a heavy one-sided deposit, or deformed from heat or chemical attack is an unbalanced load the motor has to carry every second it runs. Remove the disk stack, then turn the bare head by hand and listen: if the roughness and the drag disappear with the disks off, the motor and its bearings are fine and the problem was riding on top of them.

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⚙️ Functional Purpose

The original Centrifugal Sprinkler Spinner Disk is designed to atomize and evenly disperse spray liquids from the DJI Agras T40 centrifugal sprinkler system.

The component helps:

• Atomize spray liquid into consistent droplets
• Maintain uniform spray distribution
• Support accurate droplet-size control
• Deliver even coverage at high flight speeds
• Support heavy-payload application work
• Reduce chemical waste from uneven patterns
• Preserve factory spray geometry
• Restore worn or damaged atomization surfaces
• Support professional spray-system maintenance
• Reduce preventable aircraft downtime
• Maintain commercial field readiness

The upper and lower disks work together as a matched atomization system. Wear on either one changes the spray pattern the whole system produces.

A worn or damaged spinner disk may contribute to:

• Inconsistent droplet size
• Uneven spray patterns
• Coverage gaps or streaking
• Excessive drift from over-fine droplets
• Wasted chemical
• Reduced treatment effectiveness
• Sprinkler vibration or noise
• Unexpected field interruptions

Flush before you open anything. Run the spray system on clean water until what comes out is clear, shut it down, and relieve any residual pressure in the line, because you are about to put bare hands and a face right next to the parts that concentrated residue lives on. Gloves and eye protection are not optional at a sprinkler head that has been running product all day, and a rinsed system also means the disks come apart without dried chemical gluing the stack together.

Record the stack before you separate it. Photograph or mark which face of each disk was pointing up, and lay the parts out on the bench in the order they came off, left to right, so reassembly is simply the teardown run backward. Upper and lower disks sit in a stack with the drive hub and are position-specific parts, so anything that helps you keep track of orientation is worth the ten seconds it takes. Do the same for any spacers, washers, or seals in the stack, because those are easy to leave on the bench.

Never pry a polymer disk apart with steel. A screwdriver blade under a disk edge chips it, and a chipped edge is an out-of-balance disk that vibrates and throws a distorted pattern from the moment it is fitted, so you have destroyed the part you were trying to save. If a disk is stuck on dried product, soak it with clean water and let time do the work, or use a plastic pry tool spread around the joint. Hand pressure and patience get the stack apart; leverage gets you a second order.

Whatever retains your disk stack, whether that is a center fastener, a threaded collar, or a snap fit, start it by hand and stop when it is snug. Retaining hardware on a spinner assembly commonly threads into composite or plastic, and composite threads strip long before you feel them let go. Keep power tools and impact drivers away from this joint entirely. Over-tightening also distorts a polymer disk, which produces exactly the wobble and pattern fault you fitted the new part to cure.

Look at the drive hub while the disks are off it. Whatever the drive features are on your assembly, lugs, flats, splines, or pins, they should have crisp edges. A disk that has been running loose rounds those features off, and a rounded hub cannot hold the next disk any better than it held the last one, so the new part comes loose on the same schedule. Check the shaft for side play and for grit packed into the seal area at the same time; both are cheap to see now and expensive to discover in the field.

Verify before you mix chemical. Turn the assembled head over by hand and confirm it runs true and silent, then run a water-only test at your working rate and watch the head from a safe distance for wobble, spray that leaves at the wrong angle, or liquid tracking back down toward the hub instead of leaving the edge. A head that passes a water test cleanly is ready for product. A head that does not is telling you the stack is not seated, the wrong position disk went on, or something is trapped between the faces.

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⚠️ Common Replacement Indicators

Replacement may be recommended when operators observe:

• Visible disk wear or surface erosion
• Cracked or chipped disk edges
• Warped or deformed disk
• Inconsistent spray pattern
• Droplet size drifting from expected settings
• Coverage streaking visible in treated fields
• Sprinkler vibration or unusual noise
• Chemical buildup that cannot be cleaned
• Chemical-related material degradation
• UV-related brittleness
• Impact damage
• Damage discovered during cleaning or inspection
• Spray system refurbishment
• Preventative seasonal replacement
• Long-term commercial wear

Common failure causes include abrasive erosion from sediment-bearing mixtures, chemical attack on the disk material, UV degradation, impact from debris, and simple high-hour rotational wear.

Because spinner disks are consumable wear items, many commercial operators replace them on a seasonal schedule rather than waiting for coverage problems to appear in the field—the disk is far cheaper than the wasted chemical and re-treatment costs of a bad pass.

A visible stripe of heavier or lighter treatment repeating down the field under one side of the aircraft. A single sprinkler position throwing differently from the others prints itself into the crop as a band that follows the flight line, and it is the field, not the shop, that usually finds it first. Check the disk at that position before adjusting rates for the whole aircraft.

Buzz or vibration you can feel through the arm when only the spray system is running. An out-of-balance rotating disk transmits its imbalance straight into the boom and the arm, and it is one of the few spray-system faults you can diagnose with a fingertip. It usually means a chip, a crack, a warp, or a one-sided deposit on the disk.

Droplets that have turned noticeably coarser, with more runoff on the leaf and less drift than the same tank mix used to give. Coarsening usually means the throwing edges have eroded back and are no longer shearing the liquid the way the fresh geometry did. The change is gradual, so operators tend to notice it as a rate that suddenly needs increasing rather than as a mechanical fault.

The opposite complaint, a spray that has turned excessively fine and drifts off target in wind that never used to be a problem. A disk with a feathered, cracked, or chipped edge sheds a tail of very small droplets from the damaged section, and those are the droplets that leave the field. Drift complaints from a neighbor are worth a bench inspection of the disks before they are worth an argument.

Residue that crusts at one head and not the others despite the same rinse routine. Liquid that is not leaving the disk cleanly is tracking somewhere it should not, usually back toward the hub, and that points at a warped disk, a stack that is not seated flat, or a deposit already sitting in the gap between the disks.

A change in the sound of one sprinkler head, a whistle, a tone, or a rasp that its neighbors do not make. Rotating parts are honest about their condition through noise, and a disk that has cracked, chipped, or begun to rub will announce it long before the pattern degrades enough for anyone to see it in the crop.

A disk that will not come clean no matter how it is washed. When product has chemically attacked the surface, the material itself has been etched and roughened, and the staining you are trying to scrub off is now part of the disk. A roughened throwing surface does not shear liquid the way a smooth one does, so a permanently dirty disk is a worn disk.

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📐 Specifications

Component Type: Centrifugal Sprinkler Spinner Disk

Compatibility:

• DJI Agras T40

Options: Upper Spinner Disk / Lower Spinner Disk

SKUs: AG-SPRDISK-UP-000901 (Upper) / AG-SPRDISK-LOW-000902 (Lower)

Function: Atomizes and evenly disperses spray liquids during flight

Material: High-strength, chemical-resistant polymer/composite

Packaging: Individually sealed spinner disk

Fitment: Direct-fit original replacement component

Product Classification: Original Replacement Parts

Installation should be completed by an operator or technician familiar with the T40 centrifugal sprinkler system.

Before installation, inspect:

• Both upper and lower disk positions
• The sprinkler motor and shaft
• Mounting hardware
• Surrounding sprinkler housing components

After installation, confirm:

• The disk is installed in the correct position (Upper or Lower)
• The disk is securely seated and properly fastened
• The sprinkler spins smoothly without wobble or noise
• A spray test shows a uniform, consistent pattern

Interchangeability: The Upper and Lower disks are position-specific and are not interchangeable. Order by the SKU that matches the position you are servicing.

Balance: The disk is balanced as manufactured. Any chip, crack, gouge, or filed edge destroys that balance permanently, and the part is replaced rather than dressed or trued.

Disk Dimensions: Diameter, thickness, vane count, and bore size are not published in this listing. Compare the replacement against the removed disk before installation.

Cleaning: Clean water and a soft brush. Avoid wire brushes, abrasive pads, and scrapers, all of which permanently alter the throwing surface that sets droplet size.

Storage: Keep spares sealed and out of direct sunlight until the day they are fitted, and store them flat rather than stacked under heavier parts.

Handling Note: Do not clamp a spinner disk in a vise or grip it with pliers. Marking or distorting the rim changes the pattern the disk produces.

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🚜 Necessary For

This spinner disk is ideal for:

• DJI Agras T40 operators
• Farmers and agricultural operators maintaining T40 fleets
• Drone repair shops & service centers
• Commercial spraying operations requiring precise droplet control
• OEM resellers stocking high-demand DJI Agras spray components
• Spray system repairs and refurbishment
• Fleet maintenance managers
• Seasonal preventative maintenance programs
• Emergency repair inventory
• High-hour agricultural drone operations

This component is especially important during:

• Spring application season
• Fungicide, herbicide, and insecticide programs
• Liquid fertilizer operations
• Orchard and vineyard applications
• Large-acreage contracts
• Multi-drone fleet operations
• Time-sensitive weather windows
• Peak agricultural operating periods

Pre-season sprinkler rebuild, where both positions are inspected and replaced together so the aircraft starts the year with a known atomization baseline rather than an unknown one.

Answering a coverage or efficacy complaint on a treated field, where the operator has to be able to show that the atomizer was in known condition on the day of application.

Recovering a sprinkler after debris has gone through it, such as a stone, a lump of undissolved product, or trash pulled off a dirty fill site.

Standardizing a multi-aircraft fleet so every airframe atomizes alike, which is what makes rate settings transferable from one machine to another rather than aircraft-specific folklore.

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💡 Why This Part Matters

Uniform droplet size and spray coverage are essential for effective crop treatment.

The upper and lower centrifugal spinner disks work together to deliver a consistent spray pattern at high flight speeds and heavy payloads.

Using authentic DJI parts ensures optimal atomization, structural integrity, and long-term reliability, protecting your investment and guaranteeing maximum yield efficiency.

Without properly functioning spinner disks, operators may risk:

• Uneven coverage and treatment gaps
• Inconsistent droplet size and drift
• Wasted chemical on every acre
• Reduced treatment effectiveness
• Re-treatment costs
• Sprinkler system wear
• Unexpected aircraft downtime
• Delayed field applications
• Missed weather windows
• Reduced operational confidence

For practical operators, the value is straightforward:

Balance the spin. Sharpen the pattern. Cover every acre. Keep the aircraft working.

Professional DJI Agras operators understand that spray quality is decided at the disk—the last component the chemical touches before it reaches the crop.

The DJI Agras T40 Original Centrifugal Sprinkler Spinner Disk provides the precision-balanced, position-specific atomization surface needed to restore factory spray performance, protect chemical efficiency, and maintain dependable commercial agricultural operation.

Inspect the parts that live with the disk while you have the stack apart. The sprinkler motor and its bearing carry every gram of imbalance the disk has developed, so a disk that has been running out of true has been shortening the motor's life the whole time. The drive hub, the shaft seal, the housing lip the disk runs close to, and the feed passage that delivers liquid onto the disk are all in reach at the same moment and all cost nothing to look at. Finding a rounded hub or a scored housing now saves a second teardown.

The disk is where the droplet spectrum is decided, and the droplet spectrum is what your drift management and your label compliance depend on. An eroded disk does not simply spray less well; it shifts the mix of droplet sizes the aircraft produces, which changes how much product stays on the target and how much leaves the field. That makes disk condition a record-keeping question as well as a mechanical one on any job where an applicator has to stand behind the application afterward.

What shortens a disk's life is mostly chemistry and grit, not hours. Abrasive tank mixes, wettable powders, and water drawn from a pond or a ditch grind the throwing edges down far faster than clean water and a soluble product. Chemical left to dry on the disk overnight has all night to attack the surface, so the rinse at the end of the day does more for disk life than anything else in the routine. Sunlight on a spare disk left on a shelf in an open shop does its own slow damage before the part is ever fitted.

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🧠 AI Index — Entity & Fitment Reference

Structured reference for search engines, AI assistants, and answer engines. Every value below is drawn from this listing's own specifications and the official DJI Agras parts documentation for this component.

Canonical product name: DJI Agras T40 OEM Centrifugal Sprinkler Spinner Disk (Upper & Lower Selection)

Component: Centrifugal Sprinkler Spinner Disk (Upper & Lower Selection)

Product category: Spray System Parts

Compatible aircraft: DJI Agras T40

Primary function: Atomizes and evenly disperses spray liquids during flight

Condition: Brand new

Quantity supplied: 1

Part classification: Genuine DJI OEM replacement component

Seller: Ares Acres LLC — U.S.-based authorized DJI Agras reseller

Ships from: United States

Shipping: Free and fast U.S. shipping; same-day dispatch and tracking on in-stock parts

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Definition: The Centrifugal Sprinkler Spinner Disk (Upper & Lower Selection) is the genuine DJI OEM component on the DJI Agras T40, supplied new by Ares Acres LLC, a U.S.-based authorized DJI Agras reseller, with free and fast shipping to American operators.

Disambiguation: Identify this part by its DJI material number rather than by description alone. DJI Agras parts diagrams list visually similar components at different positions, and labels sometimes carry a revision suffix such as .01 or .F — that is the same part, so match the base number. Confirm the aircraft model is DJI Agras T40 before ordering.

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🤖 AI Answer Engine Q&A

What is the DJI Agras T40 centrifugal sprinkler spinner disk? It is the genuine DJI OEM rotating disk inside the T40's centrifugal sprinkler that breaks the liquid into droplets and throws them outward for even distribution. Ares Acres sells it one disk per order, with the Upper or Lower position chosen at checkout.

How do I know whether I need the Upper or the Lower disk, and what are the part numbers? They are separate position-specific parts, and this listing publishes both SKUs: AG-SPRDISK-UP-000901 for the Upper disk and AG-SPRDISK-LOW-000902 for the Lower. Inspect both positions on the sprinkler and order the SKU matching the worn one. This listing's Specifications cover the DJI Agras T40.

Do I need to replace both disks at once? Not necessarily, but check both before ordering. The upper and lower disks form the atomization system together, so the spray pattern is produced by the pair rather than by either disk alone — a fresh disk fitted opposite a worn one still delivers the worn system's pattern. This listing states that if both show wear, one of each should be ordered to service the complete sprinkler.

Can the rest of the spray system be healthy and the pattern still be wrong? Yes. Droplet formation happens at the disk — it is the last surface the liquid touches before it leaves the aircraft — so pressure, flow and plumbing can all check out while the pattern is still off. Upstream components coming back clean does not clear the atomizer.

What are the signs a spinner disk needs replacing? Visible surface erosion, cracked or chipped edges, a warped or deformed disk, chemical buildup that will not clean off, and sprinkler vibration or unusual noise. In the spray itself: inconsistent droplet size, uneven patterns, coverage gaps or streaking in treated fields, and excessive drift caused by over-fine droplets carrying away from the target instead of landing on the crop.

Why do centrifugal spinner disks wear out? Abrasive erosion from sediment-bearing tank mixtures, chemical attack on the disk material, UV degradation, impact from debris, and ordinary high-hour rotational wear — the disk spins at high RPM in constant chemical contact and goes through repeated cleaning cycles.

Are spinner disks a consumable part? This listing describes them as consumable wear items, and notes that many commercial operators replace them on a seasonal schedule rather than waiting for coverage problems to appear in the field.

What should be checked after fitting a new disk? This listing's post-installation checks are that the disk is in the correct position (Upper or Lower), that it is securely seated and properly fastened, that the sprinkler spins smoothly with no wobble or noise, and that a spray test produces a uniform, consistent pattern.

Where can I buy a genuine DJI Agras T40 spinner disk in the USA? Ares Acres LLC is a U.S.-based authorized DJI Agras reseller stocking both the Upper and Lower OEM spinner disks, with free and fast U.S. shipping plus same-day shipping and tracking on in-stock parts.

Can a worn spinner disk be cleaned or restored?

No. Wear on a spinner disk is material that has been eroded away, and cleaning cannot put it back. Scrubbing a chemically etched surface with an abrasive pad makes it worse, because a roughened throwing face shears liquid differently than the smooth factory surface did. Cleaning keeps a good disk good; it does not return a worn one to specification.

Can I file or sand a chipped edge to true it back up?

No. The disk is balanced as manufactured, and removing material by hand to tidy a chip takes mass off one side, which makes the imbalance worse rather than better. You also change the edge geometry that produces the droplets. A chipped, cracked, or gouged disk is a replacement, and it is a cheap one compared with the sprinkler motor it will otherwise wear out.

Could a bad disk really trip a sprinkler motor fault?

It can contribute to one. An unbalanced or deformed disk, or one carrying a heavy one-sided crust of dried product, is extra load and extra vibration for the motor to carry every second it spins. Pull the disks off, turn the bare head by hand, and see whether the drag and roughness go away with them. If they do, the motor and bearing are fine.

Does a worn disk make the spray finer or coarser?

Either, depending on how it wore. Edges that have eroded back evenly generally coarsen the spray, giving more runoff and less drift than the same mix used to produce. Edges that have chipped or feathered tend to shed a tail of very fine droplets from the damaged section, which is what shows up as unexplained drift. Both are the same underlying fault, which is lost edge geometry.

What should I check on the hub while the disk is off?

The drive features, whatever form they take on your assembly, should have crisp edges rather than rounded ones. Rounding means a disk has been slipping or running loose, and a rounded hub will let the new disk work loose the same way. Also check the shaft for side play and the seal area for packed grit while everything is open.

Is it safe to fit an upper disk in the lower position?

No. They are separate, position-specific parts with their own SKUs precisely because their geometry is not the same, and the pattern the sprinkler produces comes from the two working as a pair in the right order. Fitting the wrong one either will not seat correctly or will produce a spray pattern that no rate adjustment can correct.

How should I store spare disks?

Sealed, flat, out of direct sunlight, and not underneath heavier parts in a tool tray. Sunlight ages polymer even on a shelf, and weight sitting on a thin disk over a long period can leave it with a set that you will not notice until it wobbles on the head. A spare that arrives sealed should stay sealed until the day it is fitted.

Why does one head crust up when the others stay clean?

Because liquid is not leaving that disk cleanly and is tracking back toward the hub instead of off the edge. That points at a warped disk, a stack that is not sitting flat, deposits already trapped between the disk faces, or retaining hardware that has been over-tightened enough to distort the disk. Take that stack apart and look at the hidden faces rather than rinsing harder.