Basics of gyratory crushers

Basics of gyratory crushers

Gyratory crushers are the initial driving force for the entire mineral processing circuit. Gyratory crushers comprise a spider, main frames, a main shaft, eccentric, main drive motor, and hydraulic cylinder. The motor-driven horizontal shaft, a horizontal shaft driven by the eccentric rotation of the gear, and then driven by the eccentric portion in a circular cone movable pivot to achieve continuous extrusion crushed stones.

The main shaft can be moved up and down by adjusting the ram in the hydraulic cylinder at the bottom of the main shaft to conveniently change the size of the discharge setting and the product size distribution. At the same time, the hydraulic system serves as a tramp iron protection device. When an uncrushable object like an iron block enters the crushing chamber, the hydraulic cylinder can automatically cause the moving main shaft cone to lower, releasing the iron block and allowing the crushing to continue.

Primary gyratory crushers are built to receive run-of-mine (ROM) rocks directly from mines. Typically, metallurgical operations necessitate greater size reduction and products from primary gyratory crushers are conveyed to secondary or cone crushers for further size reduction.

Gyratory crushers, like jaw crushers, reduce size primarily through the compressive action of two pieces of steel against the rock. Continuous size reduction occurs as the distance between the two plates decreases. In addition, gyratory crushers can handle a wide range of feed particle shapes, including slabby rock.

Product features

  • With the crushing performance, the crushing chamber can be adapted to various crushing application conditions.
  • Manganese steel wear parts are standard, with optional chrome alloy concave liners and lower frame lining.
  • The effective dustproof seal includes a positive pressure blower to keep dust out of the eccentric and driving devices and to extend the life of the crusher bearing.
  • The balanced design is suitable for mobile or fixed crushing operations.
  • The heavy-duty integrated main shaft has an alloy steel threaded spindle sleeve to reduce spindle stress.
  • The moving Main shaft lock nut with the cutting ring facilitates the removal of the moving cone liner.
  • High-strength frame design can work without failure and extend service life even under severe crushing conditions.
  • The main shaft has an integrated mantle core.
  • An external backlash adjustment device for large and small gears.
  • The patent thrust bearing wear indicator reaches the worn thickness by dissolving harmless silver in the lubricating oil.
  • The main shaft position control system allows you to easily adjust the main shaft position to compensate for liner wear and control the product size.

Design benefits of gyratory crushers

A gyratory crusher consists of a solid main shaft housed within a hollow body with vertically sloping sides. When the crushing surfaces come into contact with the material it is crushed, and the crushed products fall through the discharging opening.

Hydroset design Easy automatic tramp relief and setting of a crusher gap
Spherical bearing design Less chance of component failure, i.e., extended life of components, improved machine availability and reduced operating expenses (OPEX)
More eccentric movement in the upper region of the crushing chamber
Grooved liners



Improved nipping ability
Improved PSD with fewer fines generated
Improved product shape
Energy savings up to 25%
Concave liner design Change only one row of liners at a time
Improved safety during installation and removal
Main shaft design The main shaft threaded collar shrunk to fit onto the shaft to eliminate thread on the shaft where the mantle attaches; hence no stress points
Flared outlet design Minimise possible wear on the bottom frame
Spiral bevel gear design More efficient power transfer
Lower noise level during operation


Like the jaw crusher, the largest gyratory crusher can handle boulders up to 1.5 m in length.

This crusher can handle products with a Mohs hardness between three and five.

There is no mutual sliding on grinding surfaces, only rolling of the nut on concaves. As a result, the wear is uniform and minimal.

Gyratory crushers are susceptible to jamming if sticky or moist products loaded with fines are fed into the machine.

Wear on gyratory crushers is most significant in the lower part because compression forces are applied to the entire grinding surface.

The typical reduction ratio of gyratory crushers is between four and six, similar to jaw crushers.

When the production and flow rates are equal, the power consumed by a gyratory crusher is lower than that of a jaw crusher.

Why choose IMS Engineering?

IMS Engineering offers a range of high-quality and reliable specialist solutions for crusher plants at competitive prices. Our complete range of solutions is manufactured and supplied by world-leading brands for guaranteed efficiency. This includes ETCL/Kawasaki primary gyratory crushers, cone crushers, jaw crushers, impact crushers, grinding mills and vibrating screens. With more than 60 years of experience and partnering with leading brands of specialist equipment, IMS Engineering is an industry leader and the ideal partner for your comminution mining company.

Contact IMS Engineering for details

Contact us for more information about primary gyratory crusher equipment for crushing plants. If you want to know more about our offers on other mining and industrial technology and how our team can improve your facility, chat with a representative from IMS Engineering today.


Contact IMS Engineering Today

If you would like to know more about our offers on mining and industrial technology, and how our team can improve your facility, get in touch with a representative from IMS Engineering today.

IMS Engineering (Pty) Ltd