Unsure which crusher to choose for hard rock crushing? Look no further!

Rocks are ubiquitous mineral materials in nature, but how do we classify hard rock? Generally, this can be determined by saturated uniaxial compressive strength: rocks exceeding 60 MPa are termed hard rock, while those between 30-60 MPa are classified as moderately hard rock. For example: Granite, basalt, limestone, marble, sedimentary rock, quartzite, slate, dolomite, gneiss, and others are all classified as hard rock. After crushing and sand-making processes, they can be effectively utilized in numerous fields such as highways, bridges, municipal construction, airport runways, and railways. However, to process and utilize them, a crusher is essential. Only materials processed by crushers can be utilized in the construction industry. Selecting crushing equipment requires careful consideration—choosing the right manufacturer and product is crucial. For instance, impact crushers or hammer crushers are unsuitable for hard materials, as frequent replacement of wear parts would delay production and increase costs. So, what equipment is suitable for crushing hard materials? Let's explore!

Generally, rock processing involves three main stages: primary crushing, secondary crushing, and tertiary crushing. Below, we introduce the commonly used crushing equipment for each stage.

1. Primary Crushing Stage — Jaw Crusher

The most widely used primary crusher, suitable for both hard rocks like granite and soft ores. Jaw crushers handle a broad range of materials. Domestic manufacturing processes for jaw crushers are well-established, making them the near-universal choice for primary crushing applications.

Advantages: Simple structure, reliable operation, lightweight design, cost-effective pricing, diverse models, compact footprint, large feed opening, easy maintenance, and economical operating costs.

Disadvantages: Wear plates are prone to abrasion, output tends to contain higher levels of needle and flake particles, and feeding equipment is typically required.

2. Secondary Crushing Stage — Cone Crusher

The cone crusher is undoubtedly the most widely used equipment for fine crushing of hard rock. It offers excellent wear resistance and comes in various models, including spring cone crushers, single-cylinder hydraulic cone crushers, and multi-cylinder hydraulic cone crushers. However, cone crushers are also unsuitable for crushing damp or sticky ores.

Advantages: High crushing ratio, high efficiency, low energy consumption, minimal dust generation, uniform product particle size, stable operation, low failure rate, and resistance to over-crushing.

Disadvantages: Complex structure and maintenance, tall body, and high cost.

3. Fine Crushing and Shaping Stage — Vertical Impact Crusher

If sand production isn't required downstream, the fine crushing models of cone crushers can also serve in the secondary crushing stage. For stringent product shape requirements, a sand-making and shaping machine is typically configured afterward. Vertical impact sand makers offer “stone-on-stone” or “stone-on-iron” crushing chamber configurations. For granite, which has high hardness, the “stone-on-iron” chamber isn't suitable because the peripheral liners wear out quickly, requiring frequent replacement and resulting in higher spare part costs.

Advantages: Features shaping capability, produces cubic-shaped products with high bulk density, making it a widely adopted sand-making and shaping solution in the market.

OCP Heavy Industry offers comprehensive production solutions with complimentary installation. We provide flexible customization based on user requirements and ensure timely project completion. For appointments, discounted pricing, model specifications, or design proposals, consult our customer service team free of charge or leave us a message. We will respond promptly.