How to Accept a Crushing & Screening Plant: No-Load and Loaded Commissioning Checklist

2026-10-26 08:49:45

We have manufactured wear parts for more than a decade, and half of our liners are installed during the commissioning stage of new plants — which means we have also watched many owners take silent losses at the acceptance step: nobody logs the motor current during trial runs, so when output falls short three months later, responsibility is impossible to prove; a no-load run of just two hours gets signed off, and a half-loose anchor bolt is only found after the real load goes on. This article shares the full checklist we use when supporting customers at plant commissioning: what to watch, record and gate at each stage — no-load, loaded and with-material trials.

1. The Verdict First: Acceptance Is About Three Ledgers

Many owners treat acceptance as a ceremony — the equipment turns, dust is low, material comes out, signatures follow. A professional acceptance verifies three ledgers: performance (capacity, product shape and energy use versus contract values), quality (installation precision, welding, fit clearances) and documentation (factory inspection certificates, material composition sheets, foundation settlement records). If any ledger has missing pages, later output disputes and wear-part claims have no evidence to stand on.

Quick view	Summary
Applies to	New crushing-screening plants, restarts after retrofit, EPC handover
Not for	Simple test runs after single-machine repair (flow can shrink; the ledgers cannot)
Deliverables	3-stage trial procedure + 8-item acceptance checklist + no-load/loaded criteria table
One-line advice	Run the with-material trial for at least 72 hours and log data every 2 hours — the only iron rule

2. No-Load Trial: Listen, Feel the Heat, Watch the Current

The no-load run is a health check for both machine and installation: run continuously for at least 4 hours (8 hours for large cone crushers) and capture three signals.

1. Current curve. Put a recorder on the main-drive ammeter; no-load current should hold at 30%–45% of rated. A sawtooth curve usually means tramp iron left in the feed chute. On a granite plant in northern Guangdong in 2024, unstable no-load current turned out to be an excavator tooth left inside the feeder.

2. Bearing temperature rise. Measure bearing housings every 30 minutes: for rolling bearings the temperature rise must stay below 35℃ with a peak under 70℃ (sliding bearings: rise below 25℃). A curve that climbs and then flattens is normal run-in; one side climbing nonstop means stop immediately — suspect assembly clearance or lubrication.

3. Sound and vibration. A healthy no-load run is an even rustling; metallic knocking points to foreign objects or loose liner bolts. For vibration, stand by the frame: a slight even tingle underfoot is fine, clear resonance means re-check anchor-bolt torque and damping blocks.

3. Loaded Trial: Half Load First, Then Full, Watch Both Ends

Loaded commissioning runs in two steps: 4 hours at 50% feed, then step up to full load and keep the with-material run going for at least 72 hours. Watch the inlet and the outlet:

Feed end: material must land centered. Off-center feeding causes one-sided liner wear — the No.1 reason liners deliver only half their expected life. If distribution looks segregated, reposition the feeder.
Discharge end: take a gradation sample every 2 hours. The curve should match the process design; abnormal fines usually mean a torn screen panel or liners wearing too fast.
Parameters: current, output (belt scale), discharge opening (hydraulic reading) and bearing temperatures every 2 hours — the 72-hour log is the core attachment of the acceptance report.

Crushing plant commissioning and acceptance test

4. A Signature We Almost Signed

In 2025 we supported final acceptance on a 300 t/h limestone plant in Guangxi. Everything looked fine for 70 hours; in hour 71 the belt scale slipped quietly from 300 t/h to 285 t/h — small enough for the duty operator to ignore. Cross-checking the log, the screen's current had dropped 6% at the same time: partial blinding of the screen panels by wet fines (rainy-season feed moisture). Had we signed that day, the owner would have spent three months arguing with the EPC contractor about "capacity shortfall". The value of an acceptance log lives in exactly those last two hours of data.

5. The 8-Item Acceptance Checklist (print-ready)

Item	Typical acceptance criterion	Evidence
1. Capacity	72h average ≥ 95% of contract value	Belt-scale log
2. Particle shape	Flakiness ≤ 15% (GB/T 14685 Class II) `[pending: standard year]`	Sieve analysis
3. Specific energy	≤ 2.0 kWh/t for a two-stage limestone line	Power meter + output
4. Bearing temperature	≤ 70℃, rise ≤ 35℃ (rolling bearings)	Inspection sheet
5. Noise	≤ 85 dB(A) at operator position	Sound-level record
6. Liner installation	Torque verified, backing compound full, no knocking	Installation record + material sheet
7. Safety devices	E-stops, guards and interlocked access doors all functional	Interlock test log
8. Documentation	Material sheets, factory certificates, settlement records complete	Document list

6. Three Traps Only Insiders Know

Trap 1: accepting on a smooth no-load run. 80% of liner, screen and belt problems only appear under load; no amount of empty running reveals capacity or particle shape.

Trap 2: jumping to full capacity right after acceptance. New liners need a 3–5 day run-in at about 80% load to build their initial work-hardened layer. Straight to full load chips and spalls the edges — we have seen plenty of those fragments in our lab.

Trap 3: no paperwork for the wear parts. At acceptance, cross-check the material composition sheet of every wear-part batch. Every batch we ship carries a composition sheet and supports sample-based re-verification; liners are water-toughened at about 1050℃ per GB/T 5680 `pending: standard year`. Without that page, an early liner failure three months later leaves you without even a counterparty to claim against.

7. Limitations

The cost of this procedure is time and labor: a 72-hour with-material trial means an extra week of commissioning fees and power. Small plants (below 500 t/d) can compress it to 48 hours, but none of the three ledgers should be dropped. This checklist is calibrated for aggregate/limestone lines; HPGR circuits in metal mines and cement raw-meal lines have different acceptance boundaries and need dedicated refinement.

8. Decision Matrix: How Hard Should You Test?

Project type	Recommended acceptance depth
Large aggregate plant (≥1000 t/h)	Full: 8h no-load + 4h half-load + 72h full-load, third-party testing
Mid-size plant (300–1000 t/h)	4h no-load + 72h full-load, tripartite sign-off (owner/EPC/equipment maker)
Small plants / retrofits	2h no-load + 48h full-load; focus on performance and documentation ledgers

9. FAQ: The Four Questions We Hear Most on Site

Q1: What is the minimum no-load duration?
Where the contract is silent, industry practice is 4 hours for crushing equipment and 8 hours for large cone crushers. Duration is negotiable; the current and temperature logs are not.

Q2: Who pays for the with-material trial?
Normally included in EPC commissioning fees. For pure equipment supply, the owner pays for material and power but can require the supplier's engineer on site to sign off the parameters.

Q3: When should liners be inspected first after acceptance?
First internal check after 2 weeks at full load, then weekly → monthly → quarterly. Focus: bolt torque, wear rate, any localized early failure.

Q4: Particle shape fails at acceptance — what now?
Rule out process causes first (screen aperture, feed segregation) before blaming the crusher. We once saw a wrong screen aperture mistaken for a "bad crusher"; half a day on site settled it.

10. Wear Parts for Every Station of This Line

On this line, the cone-crusher station's concaves and mantles, the jaw crusher's fixed and moving jaw plates, the ball mill's liners and grinding balls and the screen's panels are all standing Grand Heavy supply categories — quoted per ton of wear cost with a material sheet in every shipment. Foshan Grand Heavy Trading Co., Ltd. brings 40+ years of wear-material expertise and exports to 6 overseas markets including the USA, Russia and Australia, with 24-hour response from offices in Guangzhou, Foshan and Changsha.

Need acceptance support or a wear-parts quote?
Phone/WhatsApp: +8618144901190 | Email: zhouwenbin@fsgrandheavy.com | Web: www.fsgrandheavy.com

Further reading: How to configure an aggregate production line | Wear parts incoming inspection | Wear parts purchase contract | Cone crusher cavity selection