Modern excavators are loaded with productivity enhancing features, but if you don't understand the advantages built into your particular machines, you can't exploit them. Every manufacturer offers it own unique nuances. It is well worth your time to investigate the features and technology and how they can cut cycle times.
"The rule of thumb on excavators, cycle time is king," says Matthew Hendry, John Deere Construction. "To maximize performance, you want to make sure you are getting as fast of cycles as you can get. With a 20-ton machine, you are probably looking at a 9- to 10-second cycle time if you are doing things right. You go up to an 85-ton machine, and you are probably looking at an 18-second cycle time. The bigger machines are a bit slower."
Shorter cycle times reduce cost. "If you start lengthening cycle time, then your cost is going up and your production is dropping," says Hendry.
There are many universal tips that can increase effectiveness, regardless of make and model. "Experienced operators can tell you there are many tricks to maximize productivity and decrease the cost of operating any type of construction equipment," says Rob Brittain, product manager, Link-Belt Excavators. "Having the bucket teeth at the proper angle when digging maximizes productivity. Having the proper tools to assist in lifting applications saves time. You have more lifting power when the boom arm is tucked in closer to the machine. To be efficient, consider a quick coupler to shorten the time required to swap out tools."
Understand unique features
"The most important thing an operator can do to maximize the productivity of any machine is to know the equipment, and that starts with reading the operator's manual," says Brittain.
Different machines may respond better to different techniques. "John Deere and Hitachi excavators have a very strong arm," says Hendry. "We do a lot of our digging cycle with arm input as opposed to bucket curl. It is actually a faster cycle... With our excavators, you get about a 50° down angle on your teeth on the bucket. You arm in and boom up just enough to keep from stalling the arm. At about the 90° phase of the arm coming in, that bucket is about 95% full. Our machines will fill that bucket with just arm force."
Excavators without this added strength will arm in and run out of power. "You have to curl the bucket to fill it," Hendry notes. "We only require a 5° or 10° curl on the bucket to maintain that material and you are out to the spoil pile or out to the truck."
An advantage to the arm digging technique is it allows you a greater chance to feel utilities using the arm and peeling the material back than if you are curling the bucket. "You can curl up underneath it and by the time you feel it, you have usually broken it," says Hendry.
Liebherr Construction Equipment's unique hydraulic system allows the excavator to perform multiple simultaneous functions. "Due to our three-pump hydraulic system in our 30-ton and higher machines, we have a dedicated swing pump with closed loop that does not take hydraulic flow away from the attachment hydraulics," says Jeff Powell. "This allows the operator to boom up, curl or dump the bucket without slowing down."
This substantially reduces the cycle time required to dig, lift the bucket out of the hole and swing it over the side into a truck or add spoil to a pile. "With this dedicated swing hydraulic system, we can see a reduction of up to 20% in cycle time, which equates to the operator being able to move more material faster," says Powell.
Control setups can also affect operator performance. Several excavators on the market now offer short throw controls, including John Deere and Hitachi models.
"Your hands are moving a lot less on our machines than on some of our competitors," Hendry asserts. "Our engineers have done studies and found some of our competitors travel as much as a football field's distance further in a day."