Telescopic Unloader Buying Guide for Flat Grain Warehouses: How to Empty 50,000 Tonnes Without Wrecking Your Floor

Published: May 25, 2026 · Xinyada Technology · 9 min read

The day you have to empty a 50,000-tonne flat warehouse for the first time is the day you find out whether your unloading plan actually works. If the answer is a front-end loader and a crew working twelve-hour shifts, it works — until the floor cracks, the wheel loader runs over a sweep auger, or the customer demands the grain be delivered in three days instead of three weeks. A large telescopic unloader exists for exactly this problem. It is the single piece of equipment most likely to determine whether your flat warehouse is a profitable storage asset or a logistical bottleneck.

This guide explains what a telescopic unloader actually does, where it fits relative to the alternatives (front-end loader, sweep auger, pneumatic grain suction), how to size one for your facility, the procurement pitfalls that bite first-time buyers, and what FOB pricing looks like in 2026.

What a Telescopic Unloader Actually Is

A large telescopic unloader — in Chinese, da xing ba gu ji, literally “big grain-raking machine” — is a self-propelled machine that drives into a flat warehouse and excavates the grain pile from the floor up. The business end is a horizontal rotating raking head, usually a spiral or pick-up rotor, that draws kernels off the pile face and feeds them onto an enclosed inclined belt or scraper conveyor running back along the body of the machine. The conveyor discharges through a telescoping outlet boom that can extend forward, retract, and pivot, so the operator can park the unloader once and feed several outlet points without repositioning.

The machine sits on wheels or tracks. As the pile face recedes, the operator drives forward, lowers the rake, takes another bite, and walks the discharge boom across the rear conveyor or pit. A typical large unit handles between 100 and 300 tonnes per hour on free-flowing wheat, with the bigger frames climbing toward 500 t/h on shorter, simpler installations.

The key word is “telescopic.” The discharge boom extends and retracts under power, which is what lets a single machine reach the entire footprint of a wide flat warehouse without dragging hoses or rebuilding ducting between bays.

Why Flat Warehouses Need Their Own Unloading Strategy

Silos solve the unloading problem with gravity and a sweep auger. Flat warehouses do not. A flat warehouse is essentially a long shed with structural walls; the pile builds up to the roof at angle of repose and sits on a level concrete floor. There is no funnel, no central discharge, no mechanical advantage from height. Everything you load has to be physically moved out, kernel by kernel.

That mechanical reality drives three common approaches:

Wheel loaders pushing grain into a floor pit. Cheap to start with, brutal in practice. Wheel loaders generate point loads that crack floor coatings, kick up dust, leak hydraulic oil, and lose roughly 0.5 to 1 percent of grain to floor sweepings on every clean-out. They also do not work well in deep piles — once the pile is taller than the loader cab, you are pushing only the bottom layer.

In-floor scraper or sweep systems. Permanent, automated, and expensive to install. They work beautifully for the right floor plan but lock you into one layout for the life of the building, and a single mechanical failure stops the whole bay.

Pneumatic grain suction. Excellent for cleaning final residues out of a bay and for the last few hundred tonnes, but expensive per tonne at high throughput and limited by horsepower on long horizontal runs.

A telescopic unloader sits in a fourth lane. It is mobile, so one machine serves multiple warehouses or multiple bays. It works the full pile height because the rake climbs into the face. It is mechanical rather than pneumatic, so per-tonne energy cost is a fraction of grain suction at the same throughput. And it is non-destructive to the floor, which is the single biggest concern of any owner whose concrete slab represents a significant share of building cost.

Where a Telescopic Unloader Wins, and Where It Does Not

A telescopic unloader earns its keep when at least two of the following are true:

The warehouse holds more than roughly 5,000 tonnes per bay, or you need to clear it on a schedule (rail loading, vessel call, contract delivery).
Floor integrity matters — new building, epoxy coating, food-grade certification, or government storage where floor damage is audited.
You operate more than one flat warehouse and want a single mobile asset to rotate between them.
Average pile depth is more than about 4 metres, putting it out of comfortable wheel-loader range.

It is the wrong tool when bays are tiny (under 2,000 tonnes), when the grain is highly cohesive (caked soybean meal, wet maize, sugar), or when you need a permanent, hands-off automated discharge and are willing to pay for an in-floor scraper system to get it.

Sizing a Telescopic Unloader

Four numbers should appear on every quotation. If they do not, ask:

Rated throughput (t/h). Stated at a reference bulk density — wheat at 750 kg/m³ is conventional. The honest range for large machines is 100 to 300 t/h; numbers higher than that on a single rake usually depend on ideal pile angle and free-flowing material. Size for your peak emptying schedule (vessel loading, harvest dispatch), not your average daily moveout.

Working width and pile-face height. The rake bar width sets how wide a bite the machine takes per pass; the maximum face height sets how tall a pile it can attack without re-piling. Match these to the bay geometry — a machine that can only reach 5 m of face in a 7 m-high warehouse will leave the top third of every pile for a loader to push down first.

Boom reach and discharge height. The telescoping boom needs to reach your conveyor hopper, rail wagon, or truck bed without the unloader having to relocate. Measure the longest reach you actually need, then add a metre of margin for swing room.

Installed power and fuel/electric option. Larger units run 30 to 90 kW total. Indoor warehouses usually prefer electric drive (no exhaust in the bay); outdoor or remote sites often specify diesel for self-sufficiency. Some machines offer both with a quick-change power pack.

Procurement Pitfalls

Missing the “last 10 percent.” A telescopic unloader cleans 85 to 95 percent of the pile cleanly; the last few hundred tonnes always require a sweep, a small loader, or a portable grain suction unit. Budget for that follow-up equipment up front, not after the first vessel.
Underspecified discharge interface. The unloader is only as fast as the conveyor it discharges onto. If your bay-side belt or bucket elevator is rated 80 t/h, do not buy a 200 t/h unloader expecting throughput numbers it can never reach.
Ignoring door and aisle widths. Confirm the machine's transport dimensions against your warehouse doors, ramps, and turning circles. A machine that cannot enter the bay is the most expensive paperweight on the property.
Skipping dust control. An unloader working a dry wheat pile generates significant dust at the rake. Specify either a hood-and-suction package at the conveyor inlet or a sprayed-water dust suppression option, and align with whatever applies to grain dust in your jurisdiction.
No spare wear parts. Rake teeth, conveyor belting splices, and rotor scraper blades wear on a predictable schedule. Order one full spare set with the machine; international parts shipping is the most common reason for downtime in year two.
No operator training. A telescopic unloader rewards skilled operation — bite depth, boom positioning, and walking pattern affect throughput by 30 percent or more. Insist on at least one week of commissioning training included in the contract.

Indicative Pricing (FOB China, 2026)

Mid-size telescopic unloader, 100–150 t/h, wheeled, electric drive, basic boom: USD 28,000–42,000 FOB
Large telescopic unloader, 150–250 t/h, wheeled or tracked, full telescoping boom: USD 45,000–75,000 FOB
Heavy-duty unloader, 250–400 t/h, dual-power option, dust suppression package: USD 80,000–130,000 FOB
Spare wear-parts kit (rake teeth, belting, scrapers) per machine: USD 1,500–4,500
Commissioning and operator-training package on site (China travel basis): negotiated case-by-case

Allow another 15 to 25 percent for DAP or DDP delivery depending on destination port. A mid-size machine ships in a single 40-ft open-top or flat-rack container; large machines are often crated in two pieces and assembled on arrival.

Why Buyers Choose Xinyada

Xinyada Technology has been manufacturing grain handling, cleaning and storage equipment in Hebei, China for nearly fifty years — the predecessor factory was founded in 1976 — and is a long-time supplier to China’s national grain reserve and provincial grain bureau projects. We build telescopic unloaders alongside the belt conveyors, bucket elevators, and cleaning screens they discharge into, which means one supplier can deliver the full bay-clearing train rather than splitting responsibility across vendors. Standard scope includes the machine, a one-year wear-parts kit, English and Spanish operator manuals, and remote commissioning support; on-site commissioning is available on request.

Next Steps

If you are scoping unloading equipment for a new or existing flat warehouse, send us your project brief with bay dimensions, pile height, peak emptying tonnage, destination interface (truck, rail, vessel), and your port of discharge. Our engineering team will reply inside 24 hours with a sized configuration, boom geometry, and FOB / DDP quotes.

You can also browse our full bin loading and unloading lineup, or read the companion articles on belt conveyor sizing and bucket elevator selection if you are designing the conveying side of the system.