Crowd Machinery Components

CROWD MACHINERY

The crowd machinery, located at the front center of the revolving frame, consists of motor, brake, drum and gearing. A crowd rotary encoder prevents overtravel of the dipper handle. This is done by setting the limits on the panel view screen. Locating the crowd machinery on the revolving frame, instead of the boom, substantially reduces front end weight resulting in lower swing inertia and reduced required swing effort. The entire machinery unit can be removed from the machine should maintenance or overhaul become necessary.

Crowd Machinery Components

The crowd drum drives the crowd and retract rope system. Rope grooves are machined and flame hardened. The crowd and retract ropes are attached to the drum by ferrule-becket anchors which greatly simplifies rope changes.

A spring set, air released plate disc type crowd brake is mounted on the electric drive motor.

OPERATOR’S CAB

The isolated and elevated operator’s cab at the right hand front of the machinery house provides a comfortable, safe and efficient working environment for the operator. Sufficient space is provided for the fully adjustable operator’s seat, the standard operator’s display panel, and two storage lockers.

The cab is sound and heat insulated with interior walls made of a sound deadening steel-plasticsteel composite. A one-piece front window is supplied in a rugged, easy-to-change frame. A forward front window slant with over hanging roof helps keep the window clean. Transparent sun shades are provided in front and side windows.

Visibility through both side and front windows is excellent. The operator has the best view in the industry of the digging face and for truck spotting. This view is enhanced by the streamlined sides and top surfaces of the boom, unencumbered by crowd machinery or dipper handles on the outside of the boom.

The air conditioner and pressurizing unit utilizes environmentally friendly 134a refrigerant in the cooling system. Interior ducting distributes the airflow to best suit the comfort of the operator.

COMPRESSED AIR SYSTEM

The compressed air system consists of a rotary screw type air compressor, air receiver, controls and center pintle air swivel. Hydraulic high pressure hose is used throughout. The air system is used to operate all brakes and lubrication components and to perform various other functions.

AUTOMATIC LUBRICATION SYSTEM

The lube system is located in an insulated, double wall, lube room which can be heated for cold weather operation. A one ton (907 kg) monorail-mounted electric chain hoist is provided to be used to raise supplies from the ground onto the left house platform and into the lube room. Lube points on the electric motors, suspension rope pins and some dipper pins are manually accessed. All other lube points are fed from the automatic system or by oil bath.