Zero/Reduced Tailswing Wheeled Excavators.

[IBH]

I was thinking earlier today about Wheeled excavators and why with the recent development of zero (and reduced tail swing) excavators upto 30 tonnes and their greater acceptence with ever more manufacturers entering the market (e.g Volvo recently) product development has seemed to have favoured Tracked excavators over Wheeled variants.
Of the few examples I can think of that would fit the bill, most are road rail excavators such the Atlas-Terex 1404/1604 ZW 'Rail and Road Excavator' and also the New Holland MH City (?);I think Case-Poclain made a short tailswing version of the 888P in the recent past.

Are there any particular reasons why people can think of why these haven't really been developed (yet?) for more general construction useage?.

[Robban_C]

If you compare the tracked zero tail diggers with tracked non-zero tail ones in the same weight class you will probably notice that most of the zero tail ones (maybe not everyone) have a wider under carriage than their non-zero sisters. This is probably to partly compensate for the shorter "ass".
A widened u/c also gives the possibility to use a not that short tailswing so the wider u/c improves stability in several ways.

Now what about the wheeled ones? Can the under carriage be made wider to improve the stability?
According to this broschure:
http://www.volvo.com/NR/rdonlyres/8226E ... 200707.pdf
the Volvo EW140C is 2,55 m wide and that is the smallest of the wheeled Volvos. In Sweden the maximum allowed width on the roads is 2,6 m (3,1 m with signs saying "Wide Load"). I guess that it is the same in the rest of the Europe.
So the rubber ducks cannot be widened to regain some of the lost stability.
And some people call them rocking chairs as they are now.

I do not know if this is as fun in English as it is in Swedish:
A friend of mine that prefers tracked diggers calls the wheeled ones for "digging cars" (translated from the Swedish home made word "grävbil").
They usually are called "digging machines" ("grävmaskin") in Sweden.

[Nick Drew]

Interesting stuff Robban

Thanks for posting

Nick

[Robban_C]

Thanks Nick.
Note that it is my own theory, I dont know if this is the way the manufacturers think.

[Nick Drew]

Thanks Nick.
Note that it is my own theory, I dont know if this is the way the manufacturers think.

Well Robban,

That all made very good sense to me I had never thought of it like that

Nick

[Robban_C]

Saw a Hydrema rubber duck with zero tail on Blocket yesterday.

Text from ad translated:
Smooth 17ton wheeled digger with short rear end. Front dozer blade, rear utriggers (correct translation?), central lubrication system, S60 quick hitch, Encon rotortilt, hydralics for hammer, grading bucket and pallet forks. Strong digger in good kondition. 10 000 hours.

Price: 375000 +taxes

I would say that this is the exception that confirms the rule.

[Jeremy Rowland]

Very interesting Robban I agree with what you say "rubber ducks" are certainly not the most stable of machines, you would definately need some decent outriggers on a zero tailswing or it would be useless.
The one in your pic has some fitted, I always thought it was strange that Hymac didn't fit them as standard to their rubber ducks if you look at the Hymac thread ref the 610 with the grab not a stable machine.
As for zero tailswing you should look at the size of the tailswing on a Hymac 880, you could of used it to demolish buildings.

Jeremy

[IBH]

Slightly off topic, did you see the Express and Star last night Jeremy, the photo of a building being knocked down but instead of swinging a wrecking ball into it a dragline bucket was being used?

[catpeter]

Got this Cat320D LRR brand new just over one year ago.
It's really super for the type of work I'm doing mostly new sewer's and water mains.

Peter

[Jeremy Rowland]

Slightly off topic, did you see the Express and Star last night Jeremy, the photo of a building being knocked down but instead of swinging a wrecking ball into it a dragline bucket was being used?

Sorry IBH sods law I missed the E&S lastnight, where was that then? Most unusual!!

Jeremy