The PI-1 Mobile Limestone Crusher is a wheel-mounted primary impact crushing and screening plant from the CONSTMACH PI series, intended for limestone and other low-abrasion stones. The sections below summarise what it does, the materials it handles, where it sits in the crushing line, why impact crushing suits limestone, its wear parts and maintenance, and how it compares to alternative primary plants.
What does the PI-1 do?
The PI-1 combines feeding, primary impact crushing and vibrating-screen classification on a single mobile chassis. It receives run-of-quarry stone, reduces it in a horizontal-shaft impact crusher, and screens the crushed material into finished fractions, producing three or four different products at the same time.
What materials and feed sizes is it designed for?
- Designed for materials with a low grade of hardness and abrasiveness, such as limestone.
- Maximum feeding size of 900 x 900 mm.
- Stated production capacity of 150-200 t/h, depending on the hardness of the feed.
Where does it fit in the crushing line?
It operates as the primary station at the front of the line, directly at the working face. Because feeding, crushing and screening are integrated on one mobile unit, the PI-1 can deliver saleable fractions on its own or feed material on to further crushing and screening stages.
Why is impact crushing suited to limestone, and what about wear?
Impact crushers reduce material by striking it with rotor blow bars and throwing it against impact aprons, which gives a high reduction ratio and a cubical, fines-rich product favoured for limestone aggregate. Blow bars and aprons are wear-exposed, so abrasive high-silica feed wears them quickly; this is why impact-based plants like the PI-1 are matched to low-abrasion stone rather than hard, abrasive rock.
What are the main wear parts and maintenance points?
- Blow bars on the rotor and the impact aprons in the crushing chamber are the principal wear parts and require periodic inspection and replacement.
- The vibrating screen media and feeder liners are also subject to wear.
- The SIEMENS/SCHNEIDER automation and PLC, controlled by tablet, support monitoring of the crushing and screening process.
How does it compare to a jaw-based primary plant?
An impact-based plant such as the PI-1 offers a higher reduction ratio and a more cubical product in a single stage and is matched to low-abrasion limestone. A jaw-based primary plant is generally chosen for harder, more abrasive rock where impact loads and wear would otherwise be excessive. The PI-1 is the smaller plant in the series; the PI-2 provides higher capacity and a larger feed opening.
