Processes in the crushing chamber

Analytical determination of the horizontal radial force application point on the conical head of a gyratory crusher

Wear measurement on a gyratory crusher

1 Heavy duty gyratory crusher from FLSmidth

2 Feed hopper to the gyratory crusher

3 Substitute mechanical layout (kinematics)

4 Crusher cross-section with sectors

5 Distributed load on the crusher head (longitudinal and cross-section) with horizontal substitute force F_res

6 Situation at the crusher head at height h_ers

7 Substitute layout of the radial conical head load

8 Point p

Table 1: Development of the line load p(ε) and conditional equation for the force application angle δ as a function of the starting angle ε_a and exponent n

Table 2: Force application angle δ [°] (180° = π) as a function of the comminution zone ε_a to ε_e and the exponent n (some values from [7])

9 Force-displacement curve for diorite sample no. 31 [12]

10 Force-displacement curve for diorite sample no. 25 [12]

11 Installation of a gyratory crusher

For calculation of the drive torque and drive power, and design of the machine elements of gyratory crushers, a knowledge of the forces and their points of application is needed. The comminution forces acting on a crusher head can be substituted by a horizontally applied resulting force. This force acts offset by an angle to the narrowest gap. In operation with a filled crushing chamber, this angle measures around 30° to 40°. With partial filling of the crushing chamber on one side with few very hard rocks, this angle can be almost halved.

1 Introduction

Gyratory crushers, also referred to as primary gyratory crushers, primary cone crushers, round crushers, cone crushers, short-stroke cone crusher or Gates crusher [3; 4; 5; 11], are used as primary crushers in raw material extraction operations (mines, quarries) wherever large throughputs of brittle-fracture rocks or ores have to be crushed (Fig. 1). In special cases, these crushers are also employed as secondary and tertiary crushers. Comminution is effected in an annular crushing chamber which is formed from a gyrating, upwards diameter reducing crusher head and a fixed crusher...