Review: Caterpillar 623F scraper

Evolving from a one man and his horse job to a 60-ton behemoth, earthmoving machinery has a rich history. Ron Horner gets into a Caterpillar 623F elevating scraper from the heavier end of the excavator gene pool

As the bloody drought in QLD and NSW hits home hard, there is real concern that the farmers in these states are facing financial ruin unless the weather takes a drastic turn for the better, and really soon.

What turns out to be one person’s dilemma can quickly turn to favour someone else and that’s how it is today in the current erratic weather climate.

Farmers (or those whom can afford it), are taking the chance of extending, cleaning and creating new water storages while they can and also whilst the dry weather can work in their favour. In doing so, they are creating a working frenzy amongst qualified earthmoving contractors such as Danny Hope of Hope Civil in south-east QLD.

Danny runs a fleet of scrapers, all with the Cat insignia on the side and of several sizes and models; ably supported by a couple of the big dozers also in the Cat range. Danny is flat out working the rural scene in building and extending current water storage facilities in an effort to create large enough water reserves to sustain a prolonged drought once the heavens open up.

As my old mate Jack Fletcher, The King of the Kimberley (RIP), said for almost a generation, “Australia … just add water”, because without it we are buggered.

Danny has been in the game for many years and has seen so many changes within the industry. “Some good and many not so good, but that’s the way it is these days,” he says.

“I’ve got 637’s and 623’s and both are good rigs,” he claims. They are late 70 and 80 models, but the good thing about Caterpillar equipment is that it is, “Built to last and built to be rebuilt”.

“Do you know Ronnie,” he said, “I can still go into Caterpillar and buy any part I require to keep these old girls going and I maintain them to the highest level at all times.”

When I asked him about the costs of running such equipment, he replied: “Well, disregarding fuel and labour costs, tyres would have to be a big cost to keep them running. I have spent $18,000 on one single Michelin tyre for these old girls, but then again spending $10,000 on a scraper is akin to spending $200 on your family car for a service.”

Danny went on to say that work for these big girls has been patchy for a few years as the flatter, larger parcels of land suitable for subdivisions have diminished. The steeper the country, the more the clients look for excavator/dump trucks to complete the bulk earthworks jobs. However, when it comes to moving dirt and building big dams or bulk cut or fills, the scraper/dozer is the only way to go.

HISTORY OF SCRAPERS

The evolution of scrapers is as interesting as you would ever want to read.

Many of the innovative ideas that have crept or leaped into Earthmoving have evolved from the agriculture or farming industry and were born out of the need for a specific tool to carry out a local task. Necessity is indeed the mother of invention.

Not that long ago, when horses were the only mode of transport and before the advent of mechanised machinery, when everything was achieved by hard work, sweat, callused hands and back breaking chores, farmers had to construct their dams, roads and paddocks by hand and horse-drawn scoops.

It was during these days that we first saw the advent of the slip or pan scraper –­ a simple metal scoop about 1m x 1m with a built in draw bar at the front and two wooden handles at the rear (similar to an inverted modern-day wheelbarrow). The scoop was pulled by the horse across a selected area to shovel up dirt and move it to another spot. It was held in place by the farmer and, when filled and hauled into position, was tipped over on its side manually and the process started all over again.

There are so many farm dams across the length and breadth of Australia which, although may have been enlarged since, were built in this back breaking method.

The ‘Fresno’, ‘Tumblebug’ and ‘Tumblin’ Tommy’ were all names given to different variations of scoops or scrapers. Other names applicable to the evolution of scrapers were wheeled scrapers, rotary or tumblebug scraper, the mechanized wheel scraper developed in 1910 and the first rubber tyred pull scraper developed in 1932 by the late and great R.G. LeTorneau. In addition to the rubber tyres, this scraper had a large bowl capacity, cable-operated bowl for discharging and loading, and was pulled by an agricultural tractor (dozer).

This innovation soon became industry standard, as were many of Le Torneau’s inventions.

WALKAROUND

Impressive is the only way you can describe any scraper, and especially the Cat 623F. A proven 3406CTA Cat Engine, proven design, proven performance and proven reliability has this scraper at the top of the tree in my opinion.

IN THE CAB

As we clawed our way up into the cabin of the 623F Cat scraper you could be excused for becoming nauseous and nervous if it was your first trip. The cabin sits several metres off the ground and has a slightly skewed seating arrangement so the operator can view the rear of the machine as well as the front. This is to allow the operator full vision of how the material is being loaded and discharged from the trailing bowl, and on the right side of the operator’s panel beside the seat are the controls used for dropping the bowl for loading and elevating the bowl for travel and discharging.

The 48km/h, eight forward speed power-shift transmission (and one reverse) stick is in easy reach of the operator and the steering wheel can be controlled by the operator’s legs if need be. It’s all power steering and with a quick flick of the wrist you can get the nose of that machine whipping from one side to the other in quick fashion.

Gauges are easily viewed from the operator’s seat and the throttle, brake and diff lock are all located on the floor.

ON THE JOB

Running costs of these massive earthmovers don’t come cheap, with a 600-litre fuel tank and needing a top-up at the end of a heavy 10-hour shift, the 623 can load up in one minute a full-capacity load of almost 19m3 solid material in the bowl.

Pulling out filled at a 60-ton all up weight, this model Cat scraper has been a proven winner at all levels for so many years it’s not funny. In my opinion, it’s one of the best on the market.

Although the Cat 623F elevating scrapers of this configuration do not require a dozer to push fill them, it is advisable to have a dozer rip rock or any tighter material ahead of the scrapers to keep the pit clean and material plentiful and easy to load.

Discharging of material is extremely efficient, with the ability to drop the material from the bottom of the scraper bowl at a speed of 48km/h to a depth of up to 480mm. This enables the compactor to trim, level and compact the material at optimum speed, creating a very efficient and effective working environment.

From pit to pad it is advisable to have a grader to trim the haul road for greater speed and efficiency, however, scrapers have the ability to trim the haul roads upon the return journey to pit if and when required. Although fitted with a good cushion hitch to minimise the rough conditions, a major occupational health and safety issue is caused by the poor quality of the haul road conditions, which cause the operators of these rigs a great deal of discomfort and pain that over time, will develop into a workplace injury.

These “big girls”, hauling up to 60-ton in overall weight, just chew up the haul roads, creating so much dust it is advisable that a water truck, or several, are used on these projects.

THE BOTTOM LINE

As the suburban bulk earthworks projects gradually come to a grinding halt throughout Australia and moving dirt ideas change to dump trucks and excavators, scrapers are still the most efficient method of moving bulk dirt today.

Quick loading, high travel speeds and the ability to load and dump on the run yield fast cycle times, allowing these Caterpillar 623 scrapers to consistently deliver high productivity at the lowest cost per ton.

Other players in the manufacturing of scrapers have been John Deere, Le Tourneau, Wabco, Michigan, Clarke, Euclid and Caterpillar, however, many suffered from company takeovers and buyouts. Perhaps the person who played one of the most innovative and important roles in designing, manufacturing and producing scrapers was a small-time farmer from Texas, Eugene Hancock (now his is another story for another day).

Makes you wonder how the small one-horsepower, man-handled scoop, developed through necessity over 100 years ago, could evolve into this massive hulking motorised machine capable of moving mountains of material.

Irrespective of whoever claims the supreme title, there is one thing we all must appreciate – scrapers have evolved into an integral piece of earthmoving equipment that has changed the face of the mining, construction, agriculture and other industries throughout the world.

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