cedar rapids rock crushercone crusher

Cedar Rapids Rock Crusher: A Legacy of Strength and the Versatile Cone Crusher

The name "Cedar Rapids Rock Crusher" evokes a specific legacy in the aggregate processing industry, primarily referring to the robust jaw and impact crushers historically manufactured by Iowa Manufacturing Company and later by Terex® Cedarapids. In modern aggregate production, these primary crushers are often paired with cone crushers for secondary and tertiary reduction. This article provides an overview of the Cedar Rapids crusher heritage, contrasts it with the fundamental operating principles of cone crushers, and examines their complementary roles in a complete rock processing circuit.

Cedar Rapids crushers, particularly the legendary "Senior Commander" and "Junior Commander" jaw plants and horizontal shaft impactors, were engineered for high-tonnage primary crushing. They are known for their simple, durable design, ease of maintenance, and ability to handle large feed material directly from the quarry face. In contrast, cone crushers operate on a different principle. They compress rock between a gyrating mantle and a stationary concave liner, excelling at producing finer, more cubical product sizes after initial jaw or impact crushing. Their strength lies in precision reduction and consistent gradation control for final product specs.

The following table highlights the typical functional differences within a crushing circuit:

Feature	Cedar Rapids-Style Jaw/Impact Crusher (Primary)	Cone Crusher (Secondary/Tertiary)
Primary Function	Size reduction of large quarry rock (e.g., 24" down to 6").	Further reduction of pre-crushed material (e.g., 6" down to 1" or smaller).
Crushing Action	Jaw: Compressive force via fixed/vibrating plates. Impact: High-speed impact/hammers.	Continuous compressive grinding between mantle & concave.
Product Shape	Can produce more elongated fragments (especially jaw).	Generally produces more cubical end product.
Typical Stage	Primary (first break).	Secondary or Tertiary (subsequent reduction stages).

Real-World Application Case: Limestone Quarry Operation
A modern aggregate plant in the Midwestern United States utilizes this classic equipment flow. The primary crushing station employs a rebuilt Cedarapids JP3042 jaw crusher (a direct descendant of the Cedar Rapids line) to handle shot limestone from the quarry, reducing 0-36 inch rock to under 10 inches. This material is then conveyed to a secondary circuit where a Cedarapids MVP380X cone crusher takes over. The cone crusher further processes the material, precisely crushing it to produce three spec products: 1½” base rock, ¾” drainage stone, and fine chip stone for asphalt. This combination leverages the jaw's brute-force reliability for primary duty and the cone's precision for efficient final product creation.

FAQ

1. Are "Cedar Rapids" crushers still made today?
   Yes, but not under that exact name. The brand and designs are now part of Terex® MPS (Mineral Processing Systems). The current product line (like the Cedarapids® Jaques and CRC models) carries forward the engineering legacy of the original Iowa Manufacturing Company machines.

2. When would I choose a jaw crusher over an impactor as my primary?
   A jaw is typically chosen for harder, more abrasive rock (like granite) due to its compressive action and simpler wear parts. Horizontal Shaft Impactors (HSI) are often preferred for softer, less abrasive rock (like limestone) where producing a more cubical primary product is desired, even at the first stage.

3. What is the main advantage of a cone crusher in a crushing circuit?
   Its key advantage is efficient reduction with good control over final product size distribution and shape with less waste (fines generation can be managed better than with some impact styles). It is optimized for consistent output in secondary/tertiary roles.

4. Can I use just one type of crusher in my plant?
   For most commercial aggregate production requiring multiple spec products, a single machine is insufficient. A primary (jaw/impactor) breaks down raw feed efficiently, while a secondary/tertiary (cone) refines it to specification. Single-stage setups are usually limited to simple fill or rip-rap production.

5. What does "MVP" stand for in Cedarapids cone models like the MVP380X?
   MVP stands for Modular Versatile Platform. It refers to Terex® Cedarapids' design that allows quick change-out of major components like cones liners through upper-frame access, significantly reducing downtime for maintenance compared to older bushing-style cone designs.