The Gradall excavator was the idea of two brothers Koop and ray Ferwerda. The excavator was established In the 1940's during WWII, when there was a scarcity of workers. Partners in a Cleveland, Ohio construction company known as Ferwerda-Werba-Ferwerda, the brothers faced a huge dilemma when numerous men left the workforce and signed up in the military, depleting available laborers for the delicate grading and finishing work on highway projects. The Ferwerda brothers chose to build a machine that would save their company by making the slope grading task easier, more efficient and less manual.
Their initial design model was a device with two beams set on a rotating platform that was attached over a second-hand truck. A telescopic cylinder moved the beams forward and backward which enabled the fixed blade at the end of the beams to pull or push dirt. Soon enhancing the initial design, the brothers built a triangular boom to add more strength. Additionally, they added a tilt cylinder which let the boom rotate 45 degrees in either direction. A cylinder was placed at the rear of the boom, powering a long push rod to allow the machine to be outfitted with either a blade or a bucket attachment.
Gradall introduced in the year 1992, with the introduction of the new XL Series hydraulics, the most innovative adjustment in their machinery since their invention. This new system of top-of-the-line hydraulics enabled the Gradall excavator to deliver comparable power and high productivity to the more traditional excavators. The XL Series ended the initial Gradall equipment power drawn from low pressure hydraulics and gear pumps. These traditional systems successfully handled grading and finishing work but had a difficult time competing for high productivity tasks.
Gradall's new XL Series excavators showed more ability to dig and lift materials. With this series, the models were produced with a piston pump, high-pressure system of hydraulics that showed noticeable improvement in boom and bucket breakout forces. The XL Series hydraulics system was also developed together with a load-sensing capability. Conventional excavators make use of an operator to select a working-mode; where the Gradall system could automatically adjust the hydraulic power intended for the work at hand. This makes the operator's whole work easier and also saves fuel simultaneously.
When their XL Series hydraulics came onto the market, Gradall was basically thrust into the highly competitive market of machinery designed to deal with excavation, demolition, pavement removal and several industrial jobs. Marketability was further improved with their telescoping boom due to its exclusive ability to work in low overhead areas and to better position attachments.
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