Truck Frame and Crawlers

LOWER WORKS

The lower works is comprised of the truck frame, right and left crawler frames, crawler belts, propel machinery, swing rack, roller circle and collector ring system.

Truck Frame and Crawlers

CRAWLERS

The machine is provided with a crawler type mounting composed of two belts, one on each side of the truck frame. Each belt consists of links driven by a sprocket type drive tumbler. Individual crawler links are heavy alloy steel castings connected by heat treated pins.

Innovative drive tumblers made from large diameter steel castings have lugs extending beyond the tumbler rims. They are mounted on forged alloy steel shafts that turn on large anti-friction bearings mounted within the crawler frame. The sprocket type lugs provide a large area of contact against the crawler links, extending the life of both links and tumblers.

Upper and lower rollers rotate on forged steel shafts cantilever mounted from the crawler side frames for ease of maintenance and inspection. Four (4) 55" (1.39m) diameter lower rollers per frame are specially suited to withstand the periodic single point ground reaction caused by uneven pit floors. Teepee style dirt deflectors combined with vee-ring face seals prevent dirt entry into lower roller bushings. Five upper rollers on each frame support the upper crawler belt, reducing propel friction and drag. These side frames are stress relieved weldments comprised of steel castings and cold weather steel plates.

The hook surface on the inner lower edge of the crawler frame engages a rail on the bottom of the truck frame. Both parts are factory machined to ensure solid contact.