Trituradora de piedra para minería de grava en Chile

Regional Context and Materials

Common rock types in Chile for gravel

Limestone:

Carbonate rocks used for quality, clean aggregates with good chemical stability in cementitious applications; typically low in clay and organic content, with relatively consistent crushability.

Granite:

A common durable source of high-strength gravel; tends to yield well-graded aggregates after crushing but may require more energy per ton due to its hardness.

Andesite:

An intermediate volcanic rock common in the Andean region; often used for road gravel where a balance of hardness and workability is desired.

Volcanic rocks (basalts, andesites, rhyolites, tuffs):

Widespread in Chile’s volcanic belts; volcanic gravels can offer good roughness and drainage properties, but variation in porosity and wear rate is possible.

Typical Gravel Specifications in Chile

Chilean construction projects often follow standardized grain-size classifications. Some of the most common size distributions include:

• 0–40 mm: Common for road base and compacted layers
• 0–20 mm: Used for asphalt preparation and sub-base layers
• 10–20 mm and 20–40 mm: Drainage layers, concrete aggregate
• 0–5 mm (fines or sand): Filling, plastering, concrete sand mixes

Screening and grading are essential steps to ensure that gravel meets Chilean infrastructure norms (e.g., NCh standards or MOP technical specifications for public works). Consistency in grain size ensures better compaction, drainage, and bonding with binders like cement or asphalt.

What Stone Crushers Do (Technical Function)

Overview of the Crushing Process

Stone crushers are machines designed to reduce large rocks extracted from quarries into smaller, usable sizes. Gravel production typically involves multiple stages of crushing, screening, and sometimes washing.

Stage 1: Primary Crushing

• Equipment Used: Jaw Crusher
• Purpose: Reduce large boulders (300–1,000 mm) into manageable intermediate fragments.
• Process: Rock enters the jaw crusher → compressed between a fixed and a moving jaw → breaks into smaller chunks (typically 50–200 mm).

Jaw crushers are favored for their reliability in Chile’s rugged quarry environments.

Stage 2: Secondary Crushing

Equipment Used: Cone Crushers or Impact Crushers

Purpose: Refine and shape material to meet specific gravel size targets.

Cone crushers are standard for hard andesite and granite.

Impact crushers are often used for softer or more brittle materials, including some volcanic deposits.

Secondary crushers produce more uniform particles and allow closer control of final gravel gradation.

Screening and Grading

After crushing, the material moves onto vibrating screens that separate it into standardized size fractions (e.g., 0–5 mm, 10–20 mm, 20–40 mm). Oversized particles are returned to a crusher loop for reprocessing.

Case Studies: Real-World Success in Chilean Gravel Production

Road Infrastructure in Southern Chile (Araucanía & Los Ríos)

In southern regions, volcanic materials dominate. Quarries here frequently process andesite and basalt for use in public road projects.

A typical operation includes:

• Jaw crusher for primary reduction
• Cone crusher for shaping and durability
• Final screening to produce:
• 0–20 mm: Asphalt aggregate
• 20–40 mm: Road sub-base
• Washing step included to remove pumice-like dust

Portable Crushers Supporting Copper Mine Expansion in Antofagasta

In northern Chile, mining drives much of the heavy industry demand. Copper extraction sites often require temporary gravel production to build:

• Haul roads
• Processing plant foundations
• Tailings dam reinforcement berms
• Portable screening unit for grading

This configuration allows mining contractors to quickly produce 0–40 mm base material directly where needed, reducing cost and accelerating construction timelines.