As a high hardness (Moh’s hardness 7-8) and wear-resistant material, pebbles have very high requirements on wear resistance, energy consumption and particle size control of crushing equipment. For pebble sand crushing, you can choose roll crusher, roll crusher has significant advantages in the field of pebble sand making by virtue of its extrusion crushing principle and structural characteristics.

1. Core advantages of roll crusher

High efficient crushing and energy saving

Extruded crushing: 50-200 MPa high-pressure squeezing force is generated by the relative rotation of double rolls, which makes the pebbles cracked and crushed, and reduces energy consumption by more than 30% compared with the impact crusher.
Low rotational speed design: reduce mechanical wear and prolong equipment life, especially suitable for continuous operation of high hardness pebbles.

Precise particle size control

Hydraulic adjustment system: Dynamically adjust the gap between the two rolls (0.5-50 mm).  The discharge size can be controlled in the range of 2-20 mm to meet the grading requirements of construction sand. 
>Low over-crushing rate: Extrusion crushing reduces the needles and flakes particles, and the finished sand is closer to the cubic shape, which improves the strength of concrete.

Wear resistance and maintenance cost of pebble sand making equipment

Alloy roller skin: made of high manganese steel or tungsten carbide alloy, the wear resistance is improved by more than 3 times, and the life of roller skin of large equipment can reach 6-12 months.
Modular design: easy replacement of wear parts (such as roller skins, bearings), downtime reduced by 50%.

Pebble sand making environmental protection and intelligence

Low dust and noise: closed structure with dust removal device (such as pulse bag), dust emission ≤ 20 mg/m³, noise ≤ 80 dB.
>Intelligent monitoring system: real-time feedback of roller pressure and temperature data, automatically adjusting the gap to cope with changes in material hardness.

2. Sand making effect and finished product quality

Gradation optimisation

After roll crushing, the pebble sand has continuous grading, with fineness modulus controlled at 2.6-3.0 (ideal range of construction sand) and stone powder content ≤10%.

Strength Enhancement

Extrusion crushing reduces the micro-cracks inside the aggregate, and the compressive strength of concrete is increased by 10-15%.

Application Verification

The pebble aggregate processed by 1080 roller machine has been successfully used in high-speed railway concrete project, which meets GB/T 14684-2022 standard.

3. Precautions for use

Pre-treatment requirements

Cobblestone feed size should be ≤ the maximum permissible value of the equipment (e.g. 120mm for 1200 type), and oversized pieces should be roughly crushed by jaw or cone crusher first.

Anti-blocking and iron removal

Sticky pebbles need to be equipped with an iron remover to prevent metal foreign bodies, and regularly clean the roller joints to prevent clogging.</p>

Maintenance focus

Check the wear of roll surface every shift, and adjust if the gap deviation is >1 mm; the beari

ng temperature should be ≤65℃.
Roll Crusher Application Scenarios and Suggestions