Double-Toothed Roll Crusher
Coal has a low Protodyakonov hardness (f=1–3), so the crushing process itself is not the challenge; the true determinants of return on investment are the rate of fines generation (over-pulverization) and adaptability to moisture content. For a coal crushing line with an hourly capacity of 280 tons, the recommended configuration is "toothed-roll primary crushing + screening before crushing + toothed-roll secondary crushing," comprising: one ZSW490×110 feeder, one 2PGC1200×1500 double-toothed roll crusher, one 3YK2160 circular vibrating screen, and two 2PGC600×750 double-toothed roll crushers. The total installed power for the main machinery is approximately 285 kW, producing a 0–50 mm finished product. The primary crusher model is selected based on required capacity rather than feed inlet dimensions.
I. Coal Characteristics: Four Quantifiable Constraints
When selecting equipment for a 280 t/h coal crushing line, coal characteristics must first be broken down into quantifiable constraints.
Coal Crushing Production Line
1. Low hardness and high brittleness. Coal typically has a compressive strength of 10–20 MPa and well-developed bedding planes and fractures, causing it to shatter easily under pressure. Therefore, equipment selection focuses not on "whether it can be crushed" but on "uniformity of crushing"—impact crushers generate 18%–25% fines, whereas shear-type crushers can keep this figure below 10%.
2. Low bulk density. Raw coal has a bulk density of approximately 0.8–1.0 t/m³, less than half that of limestone. If nameplate capacities rated for limestone are applied directly, the selected equipment will be severely undersized; selection for coal applications must be based on ratings specific to raw coal.
3. High moisture content and susceptibility to clogging. Raw coal moisture ranges from 5% to 15%, while lignite can reach 20%–40%. Hammer crushers and impact crushers equipped with grate bars tend to clog and stall under these conditions, whereas grate-less toothed-roll crushers allow for continuous material flow.
4. Presence of iron and coal dust. Raw coal often contains roof bolts or steel wire, necessitating upstream iron removal. With a coal dust explosion lower limit of approximately 30–50 g/m³, crushing and transfer points must be enclosed with dust extraction systems and equipped with explosion-proof motors.
| Coal Characteristics | Impact on Crushing Stage | Corresponding Measures |
|---|---|---|
| Compressive strength 10–20 MPa; high brittleness | Prone to over-crushing; pulverized coal loses direct value | Shear-type toothed roll crusher; fines rate <10% |
| Bulk density 0.8–1.0 t/m³ | Nominal capacity must be rated based on raw coal | Equipment selection based on specific coal operating parameters |
| Moisture content 5%–15% (higher for lignite) | Clogging, roller adhesion, sharp drop in output | Grate-free structure + scraper device |
| Entrained iron; flammable/explosive coal dust | Dual risks: toothed roll damage and excessive dust | Iron remover + enclosed dust control system |
II. How to Select Equipment for a Coal Crushing Production Line
Equipment selection for a coal crushing production line can be summarized in five steps.
• Determine the number of stages based on the target product size: Single-stage for ≤150 mm; two-stage for ≤50 mm; smooth double-roll crusher required after the toothed roll crusher for ≤25 mm.
• Select the model based on lump coal yield: Lump coal and coke are priced by size fraction; prioritize shear-type toothed roll crushers over hammer crushers.
• Select the structure based on moisture content: A grate-free toothed roll crusher with scrapers offers the lowest risk for wet coal operations.
• Select specifications based on capacity, not feed inlet size: A capacity requirement of 280 t/h dictates the use of the 2PGC1200×1500 model for primary crushing.
• Do not skimp on safety accessories: Iron removers, enclosed dust control systems, explosion-proof motors, and anti-static conveyor belts are all essential.
III. Equipment Configuration Table for a 280 t/h Coal Crushing Production Line
The equipment configuration for this coal crushing production line is based on a maximum raw coal lump size of 500 mm, total moisture content ≤15%, and a finished product size of 0–50 mm.
| Stage | Model | Quantity | Key Parameters | Power |
|---|---|---|---|---|
| Feeding | ZSW490×110 Vibrating Feeder | 1 | Trough 4900×1100mm; Max feed size ≤580mm; 180–400 t/h | 15 kW |
| Iron Removal | RCDB Series Suspended Iron Remover | 1 | Suspended above conveyor belt; removes anchor bolts and steel wires | — |
| Primary Crushing | 2PGC1200×1500 Double-Toothed Roll Crusher | 1 | Feed ≤1000mm; Discharge ≤150mm; 150–350 t/h | 2×75 kW |
| Screening | 3YK2160 Circular Vibrating Screen | 1 | Screen surface 2100×6000mm (3 decks); Cut sizes 10/30/50mm; Oversize material sent to fine crushing | 30 kW |
| Fine Crushing | 2PGC600×750 Double-Toothed Roll Crusher | 2 | Feed ≤300mm; Discharge ≤50mm; 60–100 t/h | 2×22 kW |
| Dust Removal | DMC Series Pulse-Jet Bag Dust Collector | 1 | Enclosed dust extraction for crushing, screening, and transfer points | Customized |
| Conveying | B800/B650 Belt Conveyor | 6 | Finished product to silo; oversize material to fine crushing | — |
Installed power of main equipment = 15 + 2×75 + 30 + 2×2×22 = 283 kW (rounded to approx. 285 kW); including conveyors and dust removal, electricity consumption is approx. 1.0 kWh/t (estimated). Finished product size: 0–50mm; screen mesh can be changed to separate into fractions such as 0–10mm, 10–30mm, and 30–50mm.
IV. Four Verification Points for the Coal Crushing Production Line
The following four points are the areas where this production line design is most likely to encounter critical failures.
• Feed inlet capacity regarding raw ore lump size: The ZSW490×110 model accepts a maximum feed size of ≤580mm, suitable for 500mm-class raw coal; if the size exceeds 600mm, a fixed grizzly screen must be installed or an apron feeder used instead.
• Coarse crushing capacity alignment: The 280t/h throughput falls within the 150–350t/h operating range of the 2PGC1200×1500 crusher (80% load rate); the machine’s rated output size is ≤150mm, matching the required coarse crushing granularity for this line.
• Fine crushing capacity based on screen-oversize volume: In the coarse crushing output (0–150mm), the fraction larger than 50mm accounts for approximately 45% (approx. 126t/h). Two 2PGC600×750 units, operating with a ≤50mm roll gap, have a calculated capacity of 96–160t/h (based on 80% of nominal rating), covering the 126t/h requirement with a margin of about 21%; a conversion factor of 0.45–0.55 is applied when processing lighter materials like coke or coal gangue.
• Screen capacity alignment: The entire 280t/h coarse crushing output passes over the screen, with only oversize material sent to fine crushing; this falls within the 150–400t/h range of the 3YK2160 screen. Fine crushing output is controlled to ≤50mm and merged directly into the finished product, without recirculating to the screen.
V. FAQ
Q1 Should a double-toothed roll crusher or a hammer crusher be chosen for coal crushing?
For coal and coke priced by size grade, choose the double-toothed roll crusher: the fines generation rate is <10% (retaining 5%–15% more usable product per ton compared to the 18%–25% rate of hammer crushers); additionally, the absence of a grate bar structure prevents clogging even with moisture content exceeding 15%.
Q2 Why is a jaw crusher not used for coarse crushing in a 280t/h coal crushing production line?
Jaw crushers rely on a compression principle that results in a fines generation rate of 15%–20% and a minimum discharge size of approximately 40mm, failing to meet the requirement for a 0–50mm finished product; in contrast, toothed roll crushers offer the dual advantages of accepting large lumps and producing minimal fines.
Q3 Can continuous crushing be maintained with wet coal containing over 15% moisture?
Yes. Double-toothed roll crushers operate without grizzly bars and feature gaps between teeth to accommodate material; they typically handle raw coal and lignite with moisture content between 15% and 25%. For higher moisture or high clay content, continuous operation can be maintained by utilizing optional hydraulic roll-gap adjustment and variable-frequency feeding.
Q4 Will production capacity and particle size drift as the toothed rolls wear?
Yes. Wear on the roll surfaces causes the discharge product to become coarser; this can be corrected by making minor adjustments to the roll gap every 300–400 hours. The roll shells can be restored via hard-facing (weld overlay) 2–3 times, with the cost of a single restoration being only 20%–30% of the price of a new roll.
Q5 With an installed power of 285 kW, what is the approximate electricity consumption per tonne?
Based on an estimated load factor of 85%: (283 + approx. 40) × 0.85 &pide; 280 ≈ 0.98 kWh/t; a figure of approximately 1.0 kWh/t is used. Actual values will fluctuate depending on the coal type, moisture content, and the ratio of finished product size fractions.
Baichy Heavy Industry
Baichy Heavy Industry is a high-tech mining equipment company integrating R&D, manufacturing, sales, and after-sales service. Focusing on crushing, grinding, and mineral processing equipment, we provide professional solutions to our customers. We are ISO9001:2015 、certified, and our products include mobile crushing palnts, crawler crushing plant, construction waste crushing plants, jaw crushers, sand making machines, cone crushers, fine crushers, grinding mills, ball mills, etc., all with reliable performance to meet diverse project needs.
Baichy Heavy Industry – Your Trusted Partner
To ensure optimal performance of your equipment, Baichy Heavy Industry offers:
- Professional on-site installation guidance
- Comprehensive operator training
- 24/7 technical support & maintenance services
Our complete after-sales service system guarantees long-term, stable operation of your machinery with minimal downtime.
Protect Your Rights – Only Use Official Channels
To avoid scams and ensure authentic support, contact us exclusively through:
• Official Website: www.baichychina.com
• WhatsApp: +8615093222637
• Email: [email protected]
Your satisfaction is our priority – expect prompt, professional service every time.
(Note: Beware of unauthorized third parties claiming to represent Baichy. Always verify through official contacts.)
