SWING MACHINERY

REVOLVING FRAME

The revolving frame is the main structural member of the rotating deck. It is a welded, stress relieved structure with integral lugs for mounting the Aframe, crowd machinery and boom. Provisions are made for mounting deck extensions, operator’s cab, ballast box and swing gearcases. Machined pads on the deck locate the hoist drive motor and machinery frames.

Refer to the following page for a view of the revolving frame assembly with deck extensions and ballast box.

The revolving frame is connected to the truck frame by the center pintle.

CENTER PINTLE

The center pintle is a large diameter, hollow cylindrical forging with a flange at the top. It is threaded at the bottom with a lower nut used to hold it in place. A bronze coated steel core spherical thrust washer between the lower adjusting nut and the bottom surface of the truck frame provides a wear surface for pintle loads. The upper clamping collar at the top of the center pintle is doweled and bolted to the revolving frame to keep the center pintle from rotating.

The hollow pintle provides passage for air and grease lines and electrical cables from the revolving frame to the lower works using a swivel and collector ring assembly.