Machinery installation of a new crushing circuit is indeed a notable achievement; but it cannot, on its own, ensure operational readiness. Newly installed or upgraded processing plants are known to have many problems related to lower-than-expected throughput performance, sudden needs to order emergency spare parts, and continuous production constraints during their early ramp-up stages. The root cause of all those early life problems lies in the early operations without having put in place any critical maintenance systems, correctly calibrated instruments, and regulated control loops. The avoidance of such bottlenecks requires the implementation of a commissioning plan. Early readiness to operate needs to be done even before introducing the first batch of ore to the circuit.
The operational readiness activities should begin when the project gets sanctioned rather than wait until the completion of construction. There will be enough lead time for the maintenance staffs to conduct the asset criticality assessment, FMECA, CMMS configuration, and stocking of critical spares. Proactive asset management offers clear strategies of operation and maintenance to site staff and thus avoids failure of components prematurely in the initial stage of production.
A formal approach for pre-commissioning activities ensures the gap between construction delivery and operational commencement in the form of different stages of testing:
- Dry commissioning: test the mechanical system, electrical circuitry, drive alignment, safety interlocks, and E-stop under zero load condition to assure the proper functioning of the hardware before feeding in any media.
- Wet commissioning: run the water circuit, slurry pumps, and control interlocks under steady state condition to assure hydraulic and control integrity before bringing in rock.
- Instrument calibration: proper calibration of weightometers, power meters, density gauges, and pressure transmitters is mandatory before going for live ore test. Factory or static calibration usually drifts after installation and hence requires actual material test.
The consistency of feed is critical for the stability of the entire operation down the line. The inconsistencies in the ore particle size distribution, moisture level, or rock hardness lead to the disruption of choke feeding in the crushing units and deterioration in the screen classification performance. It is crucial for the plant operators to control stockpile feeding as well as maintain feeder surge bin levels between 50% and 80% to avoid coarse particles rilling and segregation of material. Basic process control is more important than any fancy software for the startup phase. The problem of circuit instability usually comes from the malfunctioning field instrumentation or incorrect tuning of the proportional-integral-derivative (PID) loops, not the absence of fancy controllers. Stable PID loops must stabilize basic process parameters like CSS, drive speeds, and choke bin levels first before implementing MPC or AI systems into operations. Screening optimization helps protect the crushing machines from the additional load because of removal of the qualified fines.
Sound measurement procedures are necessary for effective optimization of performance. Technical crews must track baseline measurements such as the crushing machine’s power draw, closed side settings, belt conveyor speed, reduction ratio, and liner wear characteristics. Operators need to make changes to one parameter at a time, tracking responses. Multiple parameter changes at once hide cause and effect relations thus making troubleshooting difficult. Maintenance schedules need to begin at first contact with the material being crushed. The checking of the liner wear on the crushing machine, screen deck tension, snubbers, and belt conveyor idler must take place daily so that small parts’ wear does not become a big problem.
The matrix below outlines the primary focus areas, key objectives, and operational risks eliminated during each phase of crushing circuit commissioning.
| Commissioning Phase | Key Focus Area | Target Objective | Operational Risk Avoided |
| Operational Readiness | Asset strategies, CMMS setup, and spare parts cataloging. | 100% maintenance strategy completion before first ore. | Stockouts, unassigned spares, and reactive firefighting. |
| Pre-Commissioning | Dry/wet trials, interlock checks, and instrument calibration. | Verified interlocks and baseline sensor accuracy. | Equipment damage underload and incorrect sensor readings. |
| Feed Stabilization | Stockpile control and surge bin fill management (50-80%). | Choke-fed crusher operation and zero segregation. | Choke loss, liner uneven wear, and capacity loss. |
| Control & Maintenance | PID loop tuning, screen media care, and liner tracking. | Stable closed-side setting and timely liner changeouts. | Power waste, fine re-crushing, and catastrophic breakdown. |
Successful commissioning of the crushing circuit is predicated on being prepared for the whole system, not simply on identifying problems with individual components. The three key pillars that will ensure success include:
- fully developed readiness procedures and CMMS master data completed prior to the introduction of the first tonnage of ore;
- successful consistency of the feed delivered while gaining proficiency in the base layer of process controls;
- preservation of productivity of the equipment through screening and preventive maintenance;
It is important that plant management and commissioning engineers compare their readiness checklists against these key pillars before the first run of ore.
