Idler key for track roller assembly

An idler key, comprising:

• a generally plate-like flange portion having a first centerplane of symmetry extending in a lengthwise direction;
• and
• a protrusion extending from the flange portion and having a second centerplane of symmetry extending in the lengthwise direction of the flange portion,
• wherein the first centerplane of symmetry is offset by an amount from the second centerplane of symmetry.

An idler key, comprising:

• a cast iron component having a plate-like flange portion, an elongated protrusion extending from a machined internal surface of the flange, a first step located at a base of the elongated protrusion, and a second smaller step located between the first step and external machined surfaces of the elongated protrusion,
• wherein:
• the external machined surfaces of the elongated protrusion include hardened upper and lower machined surfaces that are substantially parallel and extend in a length direction of the elongated protrusion;
• the flange portion includes a first row of fastener holes passing from an external surface through the machined internal surface at a location adjacent the upper machined surface of the elongated protrusion, and a second row of fastener holes passing from the external surface through the machined internal surface at a location adjacent the lower machined surface of the elongated protrusion;
• the first step includes machined outer surfaces;
• the second smaller step includes a machined end surface;
• and
• the cast iron component is nonsymmetrical in a width direction.