Image: Following their removal from production for engine and structural upgrades, a model 562B series was introduced and this is one of them. Even fewer of these were made than the initial production models, and this machine is even rarer as it still survives! Note the changes to panel work and the cab – which appears to be a factory fitted item. PHOTO: INTERNET
There is an inherent fascination with large pieces of earthmoving equipment, no matter what function they perform. And the rarer those machines are, the more mystique builds up around them, explains Richard Campbell.
This is certainly the case with the Allis-Chalmers 562, the largest motor scraper that Allis-Chalmers manufactured and based around a modular concept that allowed for the addition of an extra scraper bowl if necessary, and the easy replacement of components.
The machine was developed from the company’s existing TS-460 single-engined, open-bowl scraper, with which the tractor unit of the 562 shared many major components.
As Allis-Chalmers’ first attempt at a twin-powered machine, the company had great hopes for the TS-562 and its ability to make inroads into the large-capacity twin scraper market that, at the time, was dominated by the Caterpillar 657 and Euclid TS-32.
With a 30-cubic-yard bowl, and 730-flywheel horsepower at its disposal, the TS-562 certainly looked good on paper.
The TS-562 was powered by two Allis-Chalmers model 21000 turbocharged, 6-cylinder diesel engines rated at 365 flywheel horsepower each.
Completing the power train were two Twin-Disc, 5-speed powershift transmissions, and dual Allis-Chalmers Kon-Tork power transfer differentials feeding the power into identical double reduction bull gear and pinion final drives.
The machine was capable of a top speed of almost 32 mph and was usually fitted with 33.5×33-32 ply tyres.
Brakes were air actuated shoe brakes on all four wheels with a hydraulic retarder fitted to the front transmission for some extra stopping power.
Allis-Chalmers used the same design two-cylinder hydraulic steering system as fitted to their smaller scrapers which allowed full 90 degree turns to either side of centre.
The bowl
As mentioned previously, the business end of the machine held 30 cubic yards struck and 40 cubic yards of material heaped and was all-hydraulically operated with a 4-section reversible cutting edge.
Bowl raising and lowering was by two double- acting hydraulic cylinders with an unusually splayed mounting at a 30-degree angle. The apron was actuated by a single-stage hydraulic ram acting on a lever and short length of cable to raise the apron. It was lowered by gravity.
Ejection was roll out, a similar system to that employed by Euclid; the TS-562 being the only Allis-Chalmers scraper to use this manner of ejection.
Ready for action, an Allis-Chalmers TS-562 weighed 48 tons.
Home comforts
Operator efficiency was given a great deal of thought by Allis-Chalmers, and the operators compartment was roomy and well laid out with an air suspension seat, full instrumentation and well-placed operating controls.
A nice touch was the standard addition of a wide rear-view mirror across the top of the machines windscreen that allowed the operator to view the loading cycle without having to constantly turn his head and body around.
Into service
The first deliveries of the new machine were made in 1962, and initial reports were very favourable, citing plenty of power and speed. Operator opinions were also very good regarding the machine’s handling characteristics, riding qualities, and visibility compared to the opposition.
Unfortunately, then the gremlins began to appear in the form of exploding engines, multiple tyre failures (due to exceeding ton/mph ratings) and, worst of all for a large machine, structural failures.
It was not that the TS-562 was a bad machine, it was just that technology had not quite kept pace with it. Allis-Chalmers’ insufficient testing of the prototypes due to their haste to get the machine into production had led to the failures.
The machine was pulled from production after about 170 had been built.
Allis-Chalmers was not slow in addressing the problems, replacing the 21000-series engines with higher horsepower model 25000 diesel engines with the tractor unit producing 387 flywheel horsepower and the scraper 344 flywheel horsepower.
More steel was added to those areas that had been prone to structural failure, however, this in turn caused another problem as the machine was even heavier, tipping the scales at 51 tons empty. This also added to the tyre overloading issues.
Allis-Chalmers was not alone in having tyre problems caused by heat buildup and overloading. This issue affected many scraper manufacturers during the 1960s and 1970s as rubber companies scurried to keep pace with the development of high- speed earthmovers.
Allis-Chalmers renamed the TS-562, dropping the “TS” and now just calling it the 562B, and the machine, with some revised front and rear panel work, was put back into production.
The 562B was certainly an improvement on the former TS-562 when re-released, but the machine’s reputation had taken a body blow due to the previous model’s issues, with the last 562B leaving the production line in early 1967 with Allis-Chalmers citing “low sales”.
It is not known how many 562Bs were manufactured before Allis-Chalmers pulled the pin. Several prototype 562Cs were trialled, but the type was not put into series production.
No Allis-Chalmers TS-562s or 562Bs were ever imported into this country as they were considered too large for our projects (as was the slightly smaller, single-engined model TS460). Local contractors preferring the flexibility of smaller sized scrapers.
An unusual offshoot, the 555
As part of its modular concept, Allis-Chalmers had also designed a specialised twin-powered, rubber-tyred, articulated- steer push tractor, utilizing major components of the 562, which used two 562 tractor units joined by a special hitch, and fitted with a push dozer.
This was intended solely as a high-speed scraper push tractor for large jobs but, beset by technical problems, fewer than 10 were actually built.
The model 555 had disappeared from the Allis-Chalmers sales catalogue by 1965 but remains a very interesting piece of machinery.
For the model collector
Unusually for such a rare machine, a 1:50 scale model of the TS-562 does exist, manufactured by EMD Models.
This is manufactured from resin and white metal castings and looks quite imposing. It has a lot of detail but is expensive (more than $600) and is only available from a couple of specialist model retail outlets within the USA.
It is worth acquiring if you can find
one – making a change from all those Caterpillar 657s!