Learn the true components of crushing cost per tonne: energy, wear parts, labour, capital recovery. Compare quotes at same CSS and product spec.
Crushing cost is not a single number—it is the sum of energy, wear metal, labour, and capital recovery divided by the tonnes of usable product you sell. For a quarry owner, the only cost that matters is the delivered cost per tonne of finished specification, not the cost per tonne of material fed to the crusher. Before you compare quotes or change process parameters, you must define the particle size distribution, the work index of your rock, and the moisture content; without those three inputs, any cost figure is an estimate at best and a guess at worst.
This page gives you the decision framework. It will not tell you that «crusher X costs $1.50 per tonne»—no honest editor can, because the evidence depends on your site. What it will do is show you which levers reduce cost, which cost lines you are probably underestimating, and what data you must collect before you can make a final selection.
1. Energy (power) consumption
Energy is the most visible line item, but it is rarely the largest. The specific energy required to reduce rock from one size to another is governed by the rock’s Bond work index. Softer limestone will consume significantly less energy per tonne than greywacke or granite. To predict energy cost, you need the work index in kWh/t, which is a laboratory measurement—not something you can assume from the rock name.
2. Wear parts (lining and blow bar life)
This is where quarry owners under-budget most often. Wear rates depend on the abrasiveness of the rock (measured by the Abrasion Index), the crusher setting, and the feed grading. A jaw crusher with a tight closed-side setting (CSS) will consume more wear metal per tonne than the same machine with a looser CSS, because the rock is being exposed to more crushing events. If a supplier quotes a wear cost without asking for your abrasion index, treat that quote as incomplete.
3. Labour and maintenance
Planned maintenance hours are a fixed cost; unplanned stops are the real risk. A crusher that is difficult to access for liner changes will cost more in labour hours over a year than the purchase price difference between two competing models. Include the cost of a change-out crew, crane time, and the lost production during the change.
4. Capital recovery
If you run the plant for 10 years and 8 million tonnes, the crusher’s purchase price is a small fraction of the total cost per tonne. If you only run the plant for 2 years before a major rebuild, it is a very large fraction. The period over which you depreciate the machine is a management decision, not an engineering fact, but it changes your cost per tonne dramatically.
Your crushing cost is dominated by wear life, not by the purchase price. Two similar crushers can have a 15–20% difference in liner life on the same rock type, depending on the crushing chamber design and the material’s impact angle. A machine that is easy to adjust and maintain—measured by time to change liners—will save more money over five years than a machine that costs 10% less but takes double the hours to service.
The counterweight and rotor design of an impact crusher influence how evenly the wear parts are consumed. Uneven wear means you throw away usable metal and replace parts before their theoretical life is over. You cannot verify this in a brochure; you need to inspect wear profiles from real installations with the same rock type.
The single biggest mistake: quoting cost without a defined CSS. The closed-side setting determines the product size, the reduction ratio, and the wear rate. If you want a fine product, expect higher cost per tonne. If you want a coarse sub-base product, cost per tonne will be lower. Compare quotes only at the same CSS and the same product specification.
Total cost per tonne = (Energy cost + Wear parts cost + Labour + Maintenance + Capital recovery) ÷ Sellable product tonnes
Most quarry owners make two errors. First, they divide by feed tonnes instead of sellable product tonnes. If your operation produces 20% fines that you cannot sell, your cost per sellable tonne is 25% higher than the raw calculation shows. Second, they forget to include the cost of the conveyors and the screen media, which can be 5–10% of the total plant operating cost.
A worked example (with placeholder values you must replace with your site data):
This article cannot give you verified numbers for SUHMAN equipment because your site conditions are not available. To get a meaningful figure, you must provide the material work index, abrasion index, moisture, and feed gradation; without those, any cost calculation is an estimate only.
Use this table as a site-input template—fill in your figures, do not rely on someone else’s:
| Cost driver | What the buyer must provide | Why it changes your cost per tonne |
|---|---|---|
| Bond work index (kWh/t) | Test report from a certified lab | Determines energy consumption for your specific rock |
| Abrasion index | Test report or historical liner life from a nearby site | Determines wear metal cost, the largest variable line |
| Feed gradation (max size, % of fines) | Sieve analysis of quarry floor | Oversize feed stalls production; excess fines waste crushing energy |
| Moisture content | Field measurement, seasonal range | Affects screen efficiency, throughput, and clogging |
| Required product specification | Sieve curve and flakiness target | Specifies CSS, which drives wear and energy |
| P90 operating hours per year | Your planned schedule | Determines capital recovery per tonne |
| Liner change time (hours) | Ask the supplier for a documented procedure | This is the hidden labour cost over 5 years |
This table is a checklist, not a specification sheet. The blank cells are deliberate. If a supplier fills those cells with numbers before asking you for the inputs above, the numbers are likely based on a different rock type or a different product spec than yours.
A supplier quote typically includes energy and wear parts for a reference material with a known work index and abrasion index. Your rock is different. More importantly, the quote rarely includes your site-specific screen efficiency, conveyor availability, or the downtime from upstream equipment. The gap between quote and reality is mostly a gap in the assumptions about your feed. Provide the supplier with your actual sieve analysis and a rock test sample; then the quote becomes comparable .
Not automatically. A larger crusher running at partial load has a higher capital recovery cost per tonne and similar or slightly higher wear cost because the crusher is not operating in its most efficient cavity. The optimal is to match the crusher to the P80 of your feed and your required product P80. Oversizing a crusher to «have headroom» rarely pays for itself unless you plan to expand feed tonnage within two years.
For hard rock quarries, wear parts are the dominant cost centre. For concrete and asphalt recycling, steel rebar and contaminants in the feed severely reduce wear life and increase the risk of downtime for blockages. A crusher set up for a quarry may need a different rotor and apron configuration for recycling duty. If you run both applications, calculate two separate cost per tonne figures—do not average them.
There is no safe universal percentage. For an abrasive granite, wear parts can be over 50% of the total operating cost; for soft limestone, it can be as low as 20%. Instead of tracking a percentage, track wear parts cost per tonne per millimetre of CSS. That ratio tells you whether your machine setup is economical before you change suppliers. A 15% difference in this ratio between two settings is a bigger saving than any discount you can negotiate on the machine.
A VSI is often added to improve particle shape in the fine fraction, not to lower cost. Adding an extra crushing stage always increases cost per tonne, because you add energy and wear cost without adding product volume. The justification for a VSI is a higher selling price for the shaped product, not a lower operating cost. Only add the VSI if the premium on the shaped product covers the extra cost per tonne .
This framework applies to conventional quarry circuits with stable feed and a defined product specification. It does not apply to short-term contract crushing with varying materials, to very high-moisture clayish feeds that cause severe screening problems, or to installations where power supply is unreliable—in those cases, the cost model changes because downtime becomes the dominant cost line, not wear or energy. For such cases, you need to factor in the cost of generator fuel and the reduced throughput from wet sticky material before you compare any equipment.
Missing inputs for a final decision: to turn this framework into a specific cost figure for your site, you must provide the measured output from an existing circuit (tonnes per hour, product grade, and test duration), the full feed conditions (material type, hardness, moisture, max feed size), the sequence of equipment you plan to use, and the project location because local power tariffs and labour rates change the calculation significantly. Without these, SUHMAN’s editors can explain the trade-offs, but only your site data can fix the cost per tonne.
