Sand is generally divided into two categories: natural sand and manufactured sand.
Natural sand is formed under natural conditions such as rock weathering and river erosion. It consists of rock particles with a diameter below 4.75 mm (typically under 5 mm).
Manufactured sand—also known as mechanism sand—is produced by crushing rocks through sand-making machines and related equipment.

Advantages of Manufactured Sand

Compared with natural sand, manufactured sand offers higher adaptability and flexibility. It can be processed into various sizes and shapes according to different production requirements, making it more suitable for modern construction and industrial applications.

Key Factors Affecting the Gradation of Manufactured Sand

There are two major factors that influence the particle gradation of manufactured sand:

1. The crushing method used in the sand-making process
2. The screening process

The crushing method determines the internal characteristics of the sand particles, while screening plays the most critical external role in controlling the final gradation.

Role of the Vertical Shaft Impact Crusher

Among all sand-making machines, the Vertical Shaft Impact (VSI) Crusher is the most widely used. Sand produced by VSI crushers features:

• Rounded particles
• Excellent grain shape
• Well-graded particle size distribution

For this reason, VSI crushers are commonly adopted in highway construction and building materials production.

Combination of Primary and Secondary Crushing

As a secondary crushing machine, the sand maker must work in harmony with the primary crusher.

• For hard rocks, a cone crusher is usually preferred.
• For softer rocks, a hammer crusher is more suitable.

A well-designed combination of primary and secondary crushing ensures higher output, better particle shape, and continuous gradation.

Screening – The Key to Perfect Gradation

The screening stage is crucial for achieving a balanced particle size distribution. Since production specifications and capacity vary, choosing the right screening equipment requires a comprehensive evaluation of production needs and material properties.
Only by selecting properly sized and configured screening equipment can a plant produce well-graded manufactured sand that meets industry standards.

Leemay Machinery – Your Trusted Partner in Sand Production Solutions

Choosing the right crushing and screening equipment is the foundation for achieving ideal production results. When selecting a crusher, it is essential to consider not only production capacity, but also the manufacturer’s technical strength, research capability, and after-sales service.

Leemay Machinery is a professional manufacturer and exporter specializing in the R&D and production of mining and sand-making machinery. Guided by the spirit of efficiency, pragmatism, responsibility, and commitment, we are known for our professional technology, attentive service, and dedicated attitude.

Our expert engineering team can design and build production lines with a capacity of 100–3000 tons per hour, tailored to customer requirements.
We guarantee timely pre-sale consultation and responsive after-sale support—striving for 100% customer satisfaction worldwide.