Wirtgen’s 220 SM and 220 SMI surface miner suit soft rock extraction

First published in bauma Preview - February 11, 2019

Wirtgen’s 220 SM and 220 SMI surface miner suit soft rock extraction

Wirtgen has improved its 220 SM/220 SMi surface miner machine, which suit extraction operations in soft rock conditions. The basic machine is the same for the 220 SM and 220 SMi surface miner variants, although the latter has more sophisticated technology and is aimed at use in developed markets while the former is designed for emergent territories.

This machine is designed especially for use in small and medium-sized extraction operations as well as for routing work and infrastructure projects. The machine has a cutting width of 2.2m and a cutting depth of up to 300mm and can be used in rock with hardnessese of up to 50MPa. The extracted material is deposited behind the machine in a windrow and then loaded onto trucks with wheel loaders. Selective extraction makes it possible to extract raw materials with a high level of purity. The use of surface miners also reduces the amount of equipment, maintenance, and time required compared to drilling and blasting or rip-and-stack operations. In addition, refraining from drilling and blasting makes it possible to efficiently remove materials close to industrial sites and other infrastructure.

For its output the machine is compact in dimension and features smooth, hydraulic, all-track steering, allowing it a comparatively tight turning radius. The machine is powered by a diesel rated at 708kW and can reduce rock due a practical grain size, and create stable and even surfaces with precision according to the firm. The machine is also said to be manoeuvrable.

A key feature is its optimised cutting drum, which is said to be specially designed for challenging windrow applications. The high, narrow sides of the holder base is said to ensure that material flows smoothly and energy consumption is kept to a minimum. This reduces wear and tear on the housing, holders, point-attack cutting tools, and scraper blade. The machine also benefits from the firm’s latest LEVEL PRO PLUS levelling system, which has been proven in road milling applications. A flat or inclined formation level can be created with absolute precision thanks to side plate scanning and the cross-slope sensor. The machine is also ready to be equipped with GPS or laser control.