ABSTRACT
The change processes described in this chapter were observed during a study of conventional hewing longwalls in a pit where hewing was the main method of mining. They concern a change-over from single- to double-unit working and the subsequent introduction of cutting in one district of the seam in question—the Manley. These changes were the principal events in a pattern of development which brought the seam system from a steady state of low production to a new equilibrium at a higher level of productivity. Arrangements remained within the framework of conventional longwall working, though with an intensified composite component.
