To ensure the safety of the operator and others and to protect the equipment itself, an awareness of the fundamentals of excavator operation is a must. Before even turning the key, the operator should be familiar with the controls and basic excavator techniques. This will allow them to get the most out of the equipment, boost efficiency and reduce unnecessary wear and tear. This is especially important in excavator hire as any damage will incur further costs from the hire company. If caused by operator ignorance or misuse, it is unlikely to be covered by insurance. Lastly, excavators can use a lot of fuel and keeping fuel costs down through efficient use is an obvious priority.
The standard control patterns for excavators are IS0 (International Standards Organisation) and SAE (Society of Automotive Engineering). The pattern of control is reversed between systems so it is important to use the one you have been trained with. It is possible to switch from one to the other, either via a button on the display screen or a lever to the rear of the cab. ISO controls are most commonly used in Britain and are recommended for new operators.
Starting the engine is simple, first make sure the knob near the right armrest is set to ‘I’ for Idle. Turn the nearby ignition key to ‘on’ and allow the engine to run in idle for between five and ten minutes. Then turn the key to ‘start’ and in cold weather run the hydraulic systems through a few cycles.
To begin operating the excavator, raise the red lever on the left armrest to unlock the controls. Once this clicks into place, the two joysticks can be used to operate the boom and cab. In ISO controls, the right joystick controls the boom, lowering it when pulled back and raising it when pushed forward. Pushing this joystick left or right will close and open the bucket respectively.
The left joystick controls the stick and swing, extending the swing when pushed forward and drawing it back toward the cab when pulled back. To rotate the cab, push the left joystick in the desired direction. If this is held in one direction for long enough the cab will rotate through 360 degrees.
Excavators have two foot pedals with attached rods ending in two handles for driving. This allows the tracks to be controlled using hands or feet as the operator desires. This is largely a matter of personal preference, but most new operators find it easier to use the handles at first. By pushing the front of both pedals down or pushing both handles forward, the tracks will drive the excavator forward. By applying more pressure, the speed of forward movement can be increased. Pulling both handles back or pressing down on the base of the pedals near the floor of the cab will cause the excavator to reverse. To turn the excavator on the spot, use just one pedal or handle. The right pedal will activate just the right track, causing the excavator to turn left and vice versa. If the excavator is already moving, easing off on one pedal will give a smoother turn. This also causes less damage to the ground surface than turning while stationary.
After use, the cab should be rotated to face forward and square with the tracks. The red control lever should be returned to the down position to disconnect the joystick controls. Finally, the engine should be run in idle for on minute to cool down, then the ignition key turned to ‘off’.
Obviously, none of these operations should be attempted without relevant training and supervision. Excavators are large, heavy machines and can easily cause injury, death or property damage when operated by untrained individuals.
An incorrectly positioned excavator can be unstable and prone to tipping, especially with the arm extended. It should always sit on a stable, level surface that can support its weight. If the surface is uneven, earth can be packed down before positioning to make it level. When digging, the excavator should be positioned far enough back that there is no risk of falling into the hole itself. on soft or loose soil, this will need to be further back to avoid the weight of the excavator causing a cave in. If the material being removed is being loaded into trucks, the excavator should be high enough not to catch the sides or overextend the boom. If possible, load to the left so the boom does not interfere with visibility.
When working on a slope is unavoidable the excavator should always be positioned head on to the incline. The counterweight at the back of the machine gives maximum stability and the bucket can be dropped to stop any backward slide. If the tracks are parallel or diagonal to the slope the chance of tipping is greatly increased. Consult the manufacturers specifications for the maximum slope for excavator use, it can vary depending on model type.
While there are a wealth of online videos demonstrating advanced excavator techniques, it is important to master the basics first.
Firstly, mark out the line of the trench. The ideal solution is a laser level, but not all sites will have access to such sophisticated equipment. Often, stakes and string or even a line of spray paint will be enough of a guide. Position the undercarriage in line with the proposed trench with the cab aligned and facing forward. If the left track is positioned parallel with the right side of the trench the boom will be perfectly aligned for digging. Dig in layers, getting progressively deeper rather than digging to the maximum depth from the outset.
Again, a laser level can be invaluable for this, but a string level will do the same job in a pinch. Where possible, use a grading bucket attachment. These are very wide to flatten a larger ground area with the bucket edge as it is drawn toward the excavator body. The flat bottom can then be used to tamp down any remaining loose material. Once a section is level, continue with the ground next to this, using the flattened section as a guide for consistency. If a grading bucket is not available but an excavator thumb is fitted, a wooden beam or metal girder can be used. Grip this with the thumb and chain it to the bucket for a wide improvised levelling tool.
While we have only touched on the basics here, our expert staff can offer advice on many aspects of excavator use. SERV Plant Hire are plant and machinery specialists offering a huge variety of equipment for hire to the North West of England. All our construction equipment is fully certified and serviced and we are happy to answer any queries on operation and safe use. Contact us to ensure you have the best equipment for the job.