About the Caterpillar D9N Bulldozer
The Caterpillar D9 is a large track-type tractor designed and manufactured by Caterpillar Inc. Though it comes in many configurations it is usually used as a bulldozer equipped with a detachable large blade and a rear ripper attachment.
The D9, with 354 kW (474 hp) of gross power and an operating weight of 49 tons, is in the upper end (but not the heaviest), of Caterpillar's track-type tractors, which range in size from the D3 57 kW (77 hp), 8 tons, to the D11 698 kW (935 hp), 104 tons.
The size, durability, reliability, and low operating costs have made the D9 one of the most popular large track-type tractors in the world.
The D9 is a series of heavy tracked-type tractors, propelled by Caterpillar tracks and usually used as bulldozers. It came out as a prototype in 1954 as a D9X.
The D9 has undergone several generations of engineering enhancements. Each new model is denoted with an English letter added to D9 like D9E, D9G, D9H, D9L, D9N, D9R, and the current D9T. The 370 hp (280 kW) D9N replaced D8L in 1987.
The D9's primary working tools are the blade, affixed to the front and controlled by six hydraulic arms, and the optional ripper, which can be attached to the back. The blade is mainly intended for earthmoving and bulk material handling: pushing up sand, dirt, and rubble.
The rear ripper is intended for use in loosening rocky ground and ripping out larger stones.
The size, power and weight of the larger track-type tractors dictate that they are used primarily for major projects. The D9 is most commonly found in use in construction, forestry, mining, waste, and quarry operations.