DEVELOPMENT OF ADJUSTABLE EXTERNAL FEED EQUIPMENT FOR WINNING MACHINES PART II
Slowly running winning machines, such as coal ploughs equipped with activated cutting tools, require feed forces up to 300 kN for running speeds varying from 0 to 0.4 m s, whereas shearer-loaders absorb feed forces up to 400 kN for running speeds between 0 and 0.1 m s. Coal ploughs functioning on activated tools can no longer be operated as conventional ploughs with pole-reversible drives but rather, like shearer-loaders, have to adopt feed control over the full speed range. A high motor torque is necessary during standstills in order to maintain the cutting tools in coal face contact. Given the restricted space available on the plough adjustable drives must be installed in the gateroads with the plough being drawn by channel-guided chains. In the case of shearer-loaders, elasticity-induced oscillations due to external feeds have to be eliminated. The trials and simulations confirmed the effect of the elastic traction chain lengths and pretension forces on both oscillation behaviour and peak loads and consequently provided useful information on the recommended design of adjustable drives. Oscillations and performance variations can be minimised by a primary adjustment of main and auxiliary drives combined with some secondary or individual drive adjustment.
Bibliographic Reference: EUR 12654 DE (1990) 134 PP., MF, ECU 8, BLOW-UP COPY ECU 17.50 THE OFFICE FOR OFFICIAL PUBLICATIONS OF THE EUROPEAN COMMUNITIES, L-2985 LUXEMBOURG
Availability: Can be ordered online
Record Number: 1989128092900 / Last updated on: 1990-11-02
Original language: DE
Available languages: de