Winches

A winch is mounted on the rear of the dozer (fig. 11-21) and is directly geared to the rear power takeoff. This arrangement permits development of a line pull that is 50 to 100 percent greater than straight dozer pull. The winch is used for uprooting trees and stumps, hoisting and skidding felled trees, freeing mired equipment, and supporting amphibious construction operations.

Some limitations to consider when performing winch operations are the pulling capacity of the winch and the size and weight of the dozer. Also, the terrain may affect maneuverability of the dozer.

WARNING

The breakage of the wire rope is a serious hazard to both the operator and the helpers. Wire rope stretches under strain; and if it breaks, it whips with great force. The danger to the operator is greatest if the operator and dozer are in direct line with the wire rope when it is under strain. When the wire rope is under strain, everybody in the area should stand clear of the full length of the paid-out wire rope.

When rewinding the wire rope back onto the winch drum, ensure riggers hands are clear of the winch drum by at least 3 feet. Be safety conscious and ensure the wire rope used is of the best quality and meets the manufacturers' specifications and is properly inspected before use. Always wear leather-palmed gloves when handling the wire rope.

A good practice is to work a winch at less than its maximum capacity and to avoid anchoring the dozer unless absolutely necessary. Moderate loads give long life to the wire rope and winch parts and avoid severe catching on the drum. If the work is heavy, strain can be reduced by the use of pulleys and multiple lines. When pulling from the winch, always be sure to pull straight off the winch. When wire rope is pulled from an angle, it slips sideways, possibly causing damage to both the wire and winch.

OPERATING TECHNIQUES

The dozer blade is hydraulically controlled by a lever in the operator's cab. Before starting, raise and lower the blade several times to get a feel of the hydraulic control. Start all jobs, if possible, from relatively level ground. If necessary, level an area large enough to provide sufficient working space for the dozer. This prevents back-and-forth pitching of the dozer and results in better blade control.

Avoid track spinning whenever possible; this wastes effort and only converts a relatively smooth working area into ruts and piles of material that pitch and tilt a tractor. In cold weather, ruts and piles freeze and cause additional difficulty the following workday. If it rains, the ruts hold the water, resulting in wet, muddy material.

Ditches, ridges, rocks, or logs should be crossed slowly and, impossible, at an angle. his procedure slows the fall, lessens the danger of upsetting the dozer, and reduces the jolt of the fall that can be harmful to both the operator and the dozer.

When dozing, shift the dozer into low gear and feed the blade into the ground gradually until the desired depth of the cut is obtained. When you feel an increase in resistance as the load increases, start raising the blade in small increments, about one-quarter inch at a time. If you raise and lower the blade as much as 2 or 3 inches at a time while operating, the blade cuts an uneven surface over which the dozer must travel. The uneven surface will cause the dozer to nose up and down. This causes the blade to cut still more unevenly, thereby increasing the up-and-down movement of the dozer.

To carry the load with the blade, you must anticipate and compensate for the up-and-down movement of the front of the dozer. When the front of the dozer starts to nose up, you should move the control lever in the direction that will lower the blade. When the dozer starts to nose down, raise the blade high enough to compensate for the lowering of the front of the dozer. Do not over control. Raise and lower the blade only enough to compensate for the raising and lowering of the front of the tractor. Through experience, you will be able to raise and lower the blade automatically without giving it much thought or special attention.

Clearing

Clearing consists of removing brush, trees, and rubbish from a designated area. Surface boulders and other material that may be embedded in the ground should also be removed as well as any material that may interfere with the construction project.