In Hubei Province, there is a place where oranges are produced 365 days a year. Every orange on the processing line passes through precision instruments that measure weight, size, and even sugar content. But how exactly are navel oranges sorted? Here's what every citrus grower should know.
Why Navel Oranges Need Special Sorting
Navel oranges are one of the most popular citrus varieties in the world. They're prized for their sweet flavor, seedless flesh, and that distinctive "navel" at the blossom end. In Hubei Province, there is a place where oranges are produced 365 days a year—each one passing through precision instruments that measure weight, size, and even sugar content.
But here's what many growers don't realize: once an orange is picked, its quality doesn't stay the same. Sugar content continues to develop. Moisture gradually evaporates. The fruit that was perfect in the orchard can become average by the time it reaches the packing line—if it isn’t sorted quickly.
Manual sorting takes too long. Workers handle each fruit one by one, making subjective calls about size and appearance. By the time the sorting is done, some oranges have already lost their peak condition. The solution? A grading machine that sorts accurately and efficiently—before the fruit loses its value.
Two Ways to Sort Navel Oranges
Fstsort offers two main sorting technologies for navel oranges, each serving a different market need.
Roller Grader – Diameter Sorting for Standard Markets
The roller grader is the classic choice for orange packing lines. It works by diameter: oranges travel along a series of forward-moving rollers with gradually widening gaps. Smaller oranges fall through the narrower gaps first. Medium ones fall through next. The largest continue to the end. Each size exits through a separate outlet.
This is the same technology that has been used in citrus packing houses for decades—simple, reliable, and cost-effective.
What it delivers:
Feature | What It Means for Your Oranges |
|---|---|
6–10 tons per hour | High-capacity throughput for commercial packing lines |
4 adjustable grades | Sort into four distinct size grades to match different market channels |
Gentle handling | Food-grade rollers protect delicate orange skin—no bruising, no damage |
Adjustable intervals | Fine-tune grade sizes as market requirements change |
Cost-effective | Lower investment than electronic systems |
Best suited for: Standard packing lines, domestic markets, and packers who sell by size.
Electronic Weight Sorter – Precision Grading for Export
For packers supplying export markets or high-end supermarkets, weight grading offers a different advantage.
Here's why: two oranges of the same diameter can have very different weights. A dense, juice-heavy orange weighs more than a lighter, pithier one of the same size. And when buyers pay by weight—not by diameter—the weight sorter delivers what the market actually values.
Each orange is weighed individually with ±2g accuracy, then directed to the appropriate grade. Shape doesn't matter. Diameter doesn‘t matter. Only weight does.
What it delivers:
Feature | What It Means for Your Oranges |
|---|---|
±2g accuracy | Every orange goes to the right weight grade—no guesswork |
Multiple weight grades | Fine grading for export specifications |
Gentle handling | Soft weighing cups protect fruit during measurement |
Data recording | Track production volume and weight per grade in real time |
Export-ready | Meets the tight specifications of international buyers |
Best suited for: Export orders, high-end supermarkets, and packers who sell by weight.
Which One Is Right for Your Oranges?
Consideration | Roller Grader | Weight Sorter |
|---|---|---|
Sorts by | Diameter | Weight (±2g) |
Best for | Standard packing, domestic markets | Export, premium retail |
Investment | Lower | Higher |
Packing integration | Manual or semi-automatic | Fully automatic compatible |
The choice depends on one simple question: how does your buyer pay? If they pay by size, choose the roller grader. If they pay by weight, choose the weight sorter.
Beyond Sorting: A Complete Orange Processing Line
For packers who need more than just sorting, Fstsort also offers a complete orange washing, drying, waxing, and grading line—all in one continuous workflow:
1. Washing — Bubble washing or brush cleaning removes field dirt and debris
2. Drying — Air blowers remove surface moisture
3. Waxing — Liquid wax application extends shelf life and enhances appearance
4. Grading — Roller or weight sorting to match your market requirements
Explore the full specifications on our orange grading machine page →
Sort Smarter, Not Harder
Navel oranges come in all sizes. The right grader makes sure every orange finds the right market—at the right price. Whether you need high-volume diameter sorting or precision weight grading, there‘s a solution designed for your oranges.