Secondary Crusher Machine
What Is a Secondary Crusher Machine？
Secondary Crusher Machine is placed in the mineral processing flow after the jaw crusher as the core equipment of the secondary crushing stage, reducing primary crushed material from 100–400 mm down to 25–100 mm for ball mill feed or concrete aggregate specifications.
A cone-type Secondary Crusher Machine offers a reduction ratio of 6:1 to 8:1, while an impact-type unit can reach 30:1. When feed silica exceeds 15%, the cone-type machine's wear cost per ton is roughly 40% lower than that of the impact type. According to field data from 44 quarries worldwide, cone crushers tend to consume less specific energy than impact crushers in hard rock applications. Improper selection may cause actual throughput to fall 15% to 30% below design capacity, raising cost per ton by 2 to 5 RMB.
How a Secondary Crusher Machine Works: Operating Principle Explained
Both cone and impact versions of the product use mechanical force to reduce material to target size. The cone-type Secondary Crusher Machine uses inter-particle compression to crush material layer by layer, with a closed side setting range of 8 to 70 mm. The machine is widely used in hard rock crushing operations globally.
In Finland, JK Sorajaloste Oy operates a Lokotrack LT330D as its secondary unit. During a 15‑hour working day, the machine processes approximately 3,000 tonnes of material, with its diesel‑electric drive system offering fuel savings of about 15% to 20% compared with hydraulic systems. In the United States, Lexington Quarry in Kentucky has been running a 7‑foot Symons unit since 1948, still processing around 5,000 tonnes of limestone per day. In Germany, HH‑Basalt replaced an old gyratory crusher with a Sandvik CS430 in autumn 2023, achieving stable production and improved maintainability.
On 12 July 2026, during a commissioning test at a granite quarry in Jiangxi, China, a cone-type machine was adjusted from a 16‑mm closed side setting to 22 mm. Throughput rose from 280 t/h to 410 t/h, the proportion below 10 mm decreased from 68% to 51%, motor current dropped from 81% to 69% of rated value, and vibration amplitude fell from 2.1 mm/s to 1.6 mm/s. After three adjustments, the 22‑mm setting was identified as the most suitable operating point for balancing capacity and product fineness under that hard rock condition. The impact-type Secondary Crusher Machine relies on high‑speed rotor impact, achieving a single‑pass reduction ratio of up to 30:1. When feed moisture exceeds 8%, pre‑screening is recommended.
Secondary Crusher Machine Specifications: Complete Technical Data
| Parameter | Cone Type | Impact Type |
|---|---|---|
| Max feed size | 215 – 425 mm | 180 – 350 mm |
| Closed side setting range | 8 – 70 mm | 40 – 330 mm |
| Capacity | 100 – 1500 t/h | 40 – 700 t/h |
| Motor power | 220 – 750 kW | 75 – 630 kW |
| Typical reduction ratio | 6:1 to 8:1 | 10:1 to 30:1 |
When selecting the product, the maximum feed opening must be larger than the largest piece discharged by the upstream jaw crusher; otherwise, oversized material may block the feed opening. For every 1‑mm reduction in closed side setting, throughput decreases by approximately 3% to 5%.
It is advisable to determine the target product size first, then derive the required setting, and finally select a specific model based on capacity data. For purchase or pricing information, contact manufacturers with your material parameters for a quote.
Benefits of Using a Secondary Crusher Machine
The impact-type Secondary Crusher Machine can keep flaky and elongated particle content below 8%, meeting requirements for high‑grade asphalt aggregate. Hydraulic closed side setting adjustment reduces setting time from 45 minutes to 5 minutes. Additional benefits include:
Extended jaw crusher wear life: In July 2026, a limestone plant in Anhui, China, widened the jaw crusher discharge setting from 150 mm to 200 mm. Jaw die service life increased from 1,200 to 2,100 hours, while the machine handled the additional feed without issue.
Reduced unplanned downtime with intelligent control: A six‑month comparison at an iron mine in Shandong showed that two identical units—one with automatic wear compensation and one manually operated—recorded unplanned downtime of 22 hours and 92 hours, respectively.
Lower downstream energy consumption: At a copper mine in Yunnan, reducing ball mill feed size from 40 mm to 15 mm lowered grinding power draw from 28 kWh/t to 19 kWh/t.
Secondary Crusher Machine Capacity vs Discharge Setting: Real Data
The following data were recorded in July 2026 at a granite quarry in Jiangxi, China. Feed had 18% silica content, a size range of 150–250 mm, and the unit was a cone-type machine:
| Closed side setting | Throughput | <10 mm fraction | Motor load |
|---|---|---|---|
| 10 mm | 185 t/h | 78% | 92% |
| 16 mm | 280 t/h | 65% | 81% |
| 22 mm | 410 t/h | 51% | 69% |
| 30 mm | 540 t/h | 38% | 58% |
When the setting was widened from 10 mm to 30 mm, throughput nearly tripled while the fine fraction fell by half. Compared with published data for similar machines, the 410 t/h at 22 mm is roughly 8% above the industry average, while motor load of 69% is below the average of 75%, indicating a good balance between throughput and energy consumption at this setting. When the setting exceeds 25 mm, adding a closed‑circuit screening system is recommended to ensure final product meets size specifications.
Secondary Crusher Machine Applications by Material Type
The product is used with various material types worldwide:
Granite and basalt: A cone-type machine is preferred. Wear part costs are roughly 0.8 to 1.2 RMB per tonne. In Finland, JK Sorajaloste uses an LT330D to process granite.
Limestone and dolomite: An impact-type Secondary Crusher Machine is commonly used, accounting for over 70% of installations in cement raw material lines. The Symons unit at Lexington Quarry processes about 5,000 tonnes of limestone per day.
Concrete and construction waste: An impact-type unit is suitable, producing recycled aggregates with water absorption of about 5% to 8%, usable in low‑grade concrete and road base.
Iron ore and copper ore: A cone-type machine is standard, with a configuration rate above 90% in hard rock mineral processing plants.
How to Choose the Right Secondary Crusher Machine: Selection Guide
Selecting the product involves evaluating five key factors:
Feed silica content: When silica exceeds 15%, a cone-type machine is recommended; when below 12%, an impact-type machine is more suitable.
Closed side setting: Based on field data above, every 5‑mm reduction reduces throughput by about 20% to 25%.
Reduction ratio requirement: If total required reduction exceeds single‑pass capability, a closed‑circuit arrangement should be used. This typically reduces throughput to 70%–80% of open‑circuit capacity but ensures product size control.
Annual operating hours: For plants running more than 5,000 hours per year, an automatic control system is advisable. Data from the Shandong iron mine shows unplanned downtime reduction of over 70%.
Site conditions: Available space, foundation load capacity, and compatibility with upstream and downstream equipment also influence the final choice.
Secondary Crusher Machine Maintenance: Daily Checks and Best Practices
More than 60% of unplanned downtime for the product is due to lubrication system issues. During early operation at the Jiangxi quarry, wrong lubricant viscosity caused two instances of bearing over‑temperature; switching to a lower‑viscosity oil resolved the problem. At the Nordkalk mine in Finland, wear parts on the machine are replaced after approximately 18 months of continuous production. Daily maintenance practices include:
Every 8 hours: Check lubricating oil level and quality. For a cone-type Secondary Crusher Machine, use low‑viscosity oil when ambient temperature falls below 5°C.
Each shift: Verify closed side setting using the lead‑block compression method. Re‑adjust if deviation exceeds 2 mm.
Weekly: Record remaining liner thickness. When it falls below 20% of initial thickness, order replacement parts at least two weeks in advance. Jiangxi data from July 2026 indicate that at 18% silica and 16‑mm setting, liner life is about 1,200 hours.
Monthly: Test hydraulic overload protection response time. If it exceeds 3 seconds, service the hydraulic valve group.
Frequently Asked Questions About Secondary Crusher Machine
Cone vs impact Secondary Crusher Machine: which saves more energy?
For hard rock, cone-type units consume about 1.2 to 1.8 kWh/t, while impact-type units consume about 2.0 to 2.8 kWh/t. For limestone, the difference is less than 10%. These figures are based on a study covering 44 quarries worldwide.
How to prevent blockage in a Secondary Crusher Machine with wet feed?
Cone-type machines can handle feed with 8% to 12% moisture. Impact-type units are more prone to blockage above 8% moisture; pre‑screening or reducing moisture to below 7% is recommended.
How long does liner last on a Secondary Crusher Machine?
Jiangxi field data from July 2026 show that with 18% silica granite, liner life for cone-type units is about 1,200 hours at 16‑mm setting and extends to over 1,700 hours at 22‑mm setting. At the Nordkalk limestone mine, liner life is approximately 18 months.
What is the capacity impact of closed-circuit on a Secondary Crusher Machine?
Throughput typically falls to 70%–80% of open‑circuit capacity, but final product can be fully controlled to pass screen aperture. This suits applications with strict maximum particle size requirements, such as aggregates and mill feed. For pricing or purchase information, contact manufacturers with your specific parameters for a quote.
