The question is not whether you can make 0–5 mm particles. It is whether the grading curve, the fines content and the particle shape will pass your concrete producer's specification, every day, in the rainy season.
Natural river sand is increasingly restricted or banned across Southeast Asia and parts of Africa, and the price of compliant concrete sand has risen accordingly. Manufactured sand fills that gap — but only if it is genuinely compliant. Sand that is too coarse, too flaky or too high in fines causes workability problems at the batching plant, and the producer will reject the load regardless of the price.
Three properties decide whether your M-sand sells: gradation (the full curve, including the fine end, not just the top size), particle shape (cubical rather than flaky, which is a VSI advantage), and fines and silt content (controlled by the process — dry with air separation, or wet with washing and dewatering).
Our relevant experience: we built and run a 500 t/h construction-waste wet-process line in Hangzhou, including the wet sand process used through the region's rainy season. That is first-hand operating experience with the exact problem that stops most tropical sand lines in month four: wet feed blinding the screens and pushing the fines content out of spec.
| Consideration | Dry process | Wet process |
|---|---|---|
| Water requirement | None (or minimal dust suppression) | Substantial — make-up water, settling pond or thickener |
| Fines & silt control | By air separation and deck selection; harder to control on a fine curve | Directly controlled by washing and dewatering — best product consistency |
| Rainy season performance | High feed moisture blinds screens and drops throughput | Designed for wet feed; maintains throughput and spec |
| Footprint & cost | Smaller, lower capital cost | Larger: water circuit, settling, dewatering screens |
| Best for | Dry climates, low-moisture feed, moderate fines targets | Monsoon and tropical climates, tight concrete specs, C&D-waste feed |
0–40 mm crushed product from the aggregate side, screened and de-dusted. Feed gradation matters: too much −5 mm in the VSI feed wastes power and inflates fines.
Rock-on-rock as standard for shape and lower wear cost. Rotor speed is the tuning screw for the fines curve — we set it with you at commissioning, using your actual product test.
Closed circuit: oversize returns to the VSI. Screen apertures and deck count set the top size and the intermediate cuts.
Wet process: washing plus SJ.TS dewatering screens, water recovered to the process. Dry process: air separation and, where needed, a cyclonic classifier.
| Stage | Equipment | Model | Qty | Power (kW) | Note |
|---|---|---|---|---|---|
| Feed screening | Circular vibrating screen | SJ.Y.2.A.24.60 | 1 | 30 | Removes −5 mm ahead of VSI |
| Sand making | VSI sand maker | SJ.L.500 | 1 | 250×2 | Rock-on-rock, closed circuit |
| Sand screening | Circular vibrating screen | SJ.Y.3.A.27.60 | 1 | 37 | 3-deck: 0–5 / return / waste |
| Dewatering (wet) | Dewatering screen | SJ.TS.22.45 | 1 | 11×2 | Wet process only |
| Sand washing (wet) | Sand washer | wheel / screw | 1 | — | Supplied to the silt spec |
| Process water (wet) | Settling / thickener circuit | — | 1 | — | Water returned to process |
Sand yield in this arrangement is typically 35–55% of VSI throughput, depending on feed gradation and target curve. Figures above are indicative; the configuration sheet for your project is produced from your own feed analysis.
In most of the markets we serve it already has, either because river sand is restricted or because the price gap makes it uneconomic. The commercial test is simple: compare the delivered cost of compliant M-sand from your own line against the local river-sand price. We usually build that comparison into the quotation.
A cone sand maker compresses the rock; a VSI breaks it by impact. The VSI gives a cubical particle and a more controllable fines curve, which is what concrete specs reward. The cone version is cheaper to buy and run, and is fine where the spec is loose. We build both and will recommend honestly — see the VSI product page for the detail.
It depends on your feed and your silt target, and it is one of the things we size during configuration. In practice most plants recirculate the bulk of it through a settling or thickener circuit, so make-up water is a fraction of the circulation rate — but you need to plan the pond or thickener footprint.
Usually yes. If the structure and conveyor take-off points were designed with the possibility in mind, adding a VSI and a screen is a reasonably contained project. If not, it is still possible but involves more structural work. We will assess an existing plant — including one we did not supply.
We will return a process recommendation (dry or wet), an equipment list and a yield estimate — including the per-ton wear cost that decides whether the line pays.