How to Reduce Fines in Manufactured Sand Production
For sand producers in India and Vietnam, excessive fines (particles below 0.075 mm) can downgrade manufactured sand and cause rejection from concrete plants. Learning how to reduce fines in manufactured sand production helps you meet standards like IS 383 (India) or TCVN 9205 (Vietnam) while improving product value. Fines content above 10‑12% increases water demand and reduces strength. Below we share practical methods to control fines without sacrificing yield, based on OCP Mechanical Company’s experience with Type V VSI and sand processing equipment.
Adjust Rotor Speed and Cascade Ratio
The first step in how to reduce fines in manufactured sand production is optimizing the VSI’s operating parameters. Rotor speed directly affects the amount of fines generated. Higher speed (1,800‑2,000 rpm) creates more fines; lower speed (1,400‑1,600 rpm) produces coarser sand. For hard rock like granite or basalt, start at 1,500 rpm and measure the passing 0.075 mm. If fines are above 12%, reduce speed by 50‑100 rpm. Also, increase the cascade ratio (bypassing some feed directly to the chamber) – a cascade of 20‑30% can lower fines by 2‑4 percentage points while maintaining shape.
Note: Product data are constantly updated; for the latest VSI parameters, please contact our online customer service.
Many sand plants in Maharashtra and Binh Duong have reduced fines from 15% to 9% simply by lowering rotor speed and adding 25% cascade.
Use an Air Classifier or Dry Screen
Another effective method for how to reduce fines in manufactured sand production is mechanical classification. For dry sand, a static or dynamic air classifier can remove ultrafines (down to 0.045 mm) by creating a controlled air flow. The classifier can be adjusted to cut at 0.075 mm. Alternatively, a high‑frequency vibrating screen with fine mesh (0.1‑0.2 mm) can separate some fines, but blinding is an issue with wet material. For moist sand, a hydrocyclone is more efficient.
OCP offers both air classifiers and high‑frequency screens as optional modules. Many producers in Tamil Nadu and Hanoi have lowered fines to 6‑8% using a multi‑stage air classifier after the VSI.
The above values are for illustration only. OCP continuously improves its products. Contact our online team for the most current data sheet.
Optimize Feed Gradation and Moisture
Feed characteristics play a role in how to reduce fines in manufactured sand production. A feed with a high proportion of fines already present will increase the fines in the product. Pre‑screen the VSI feed to remove material below 5 mm. This reduces the amount of fine material entering the crusher. Also, dry feed (below 3% moisture) tends to generate more fines than slightly moist feed (3‑5% moisture) because dry material fractures more easily. Spray a fine mist of water at the VSI feed point – just enough to dampen without causing packing.
OCP’s Type V VSI can be equipped with a water spray system for dust and fines control. Many Vietnamese operators have found that adding 2‑3% moisture reduced fines by 15‑20%.
Combine with Sand Washing
For the strictest specifications, the most reliable answer to how to reduce fines in manufactured sand production is washing. A screw washer (Type W) can remove fines down to 0.075 mm, typically reducing content from 12‑15% to 5‑8%. Hydrocyclones can cut at 0.045 mm for ultra‑clean sand. However, washing increases water consumption and creates a settling pond requirement. In water‑scarce regions, an air classifier is a better choice.
As a direct‑selling manufacturer, OCP supplies complete sand processing lines including VSI, screens, air classifiers, and washers. We keep local spare parts in India and Vietnam.
Why OCP Is Your Partner for Fines Control
Understanding how to reduce fines in manufactured sand production helps you produce a higher‑value product. OCP Mechanical Company has over 40 years of history in sand making technology. We offer:
Free pre‑sale fines analysis and reduction recommendations.
Factory‑direct VSI, air classifiers, and sand washers with 24/7 support.
24/7 online technical service for parameter tuning and troubleshooting.
For a no‑obligation consultation and personalized advice on how to reduce fines in manufactured sand production, simply click the live chat icon on this page. Our online customer service team is available 24 hours a day, 7 days a week, to answer your technical questions, provide free recommendations, and help you produce specification sand for the Indian and Vietnamese markets.
