|023 — Direktlink
12.06.2013, 15:20 Uhr
in einem Artikel in der Cranes Today wird die Geschichte der Knicklenker-Krane in Australien recht ausführlich dargestellt (Autor: Greg Keane, Datum: 8. Dezember 2008):
(Ich zitiere hier mal den ganzen Artikel direkt, um entsprechende Kommentare einfügen zu können)
The kangaroo of the world
Australian pick and carry cranes are like the continent's well-known marsupials: they are rather funny-looking, but they are good at what they do and wholly adapted to their environment. Greg Keane reviews the history and the future of these multi-tasking articulated cranes.
Australia can rightly be regarded as the home of the pick-and-carry crane. The design was born during World War II, when trailed cranes were the most common type of pick-and-carry crane used in handling stores, with cranes of this type brought to Australia by US forces. The crane section was mounted on a turntable, and trailed behind a truck or tractor when travelling. For positioning the load, the crane gooseneck was sufficiently tall that the truck or tractor could turn under the gooseneck to face the hook.
Australian engineer Laurie Hardman had the idea that the front axle of the prime mover could be dispensed with, to create an articulated crane that was more manoeuvrable. This crane had a 5-ton capacity, and changed little in basic design until the early 1970s. Manufacturer Fowler protected this design with patents, which partly explained the lack of change.
The most significant advance in the tractor crane was the BHB crane, based on the Australian Chamberlain Industrial tractor. Apart from being a cleaner design with a single, underslung articulation point (the Fowler crane had an articulation point above and below the tractor), the Chamberlain tractor was stronger and more mobile than the International and Fordson tractors commonly used by other manufacturers. When manufacture of the Chamberlain tractor was discontinued, this was virtually the death knell of the tractor crane. Other tractors were tried but they did not measure up, and tractor units were designed and built by some of the crane manufacturers, but where the tractor unit was purpose-built there was no need for it to look like a tractor. The BHB/Chamberlain tractor cranes did establish a market for a mobile machine that could operate as a taxi crane. In the early era of the tractor crane, truck cranes using drivetrains derived from British trucks were certainly no greyhounds, and the BHB tractor cranes lost little in terms of mobility.
Das ist ein Beispiel für die eben genannten knickgelenkten Chamberlain Tractorcranes, hier schon mit Teleskopausleger. Die älteren Versionen gab es auch mit festem Gitterausleger oder ganz früher sogar ohne Winde, sondern nur mit festem Haken, aber immer mit Hydraulikzylinder gewippt.
One factor that is often not appreciated by the rest of the world, and which in part explains some of the peculiarities of Australian crane preferences, is that while Australia is a vast continent, it is highly urbanised around the major population centres on the east coast. At the time when the tractor crane market developed, there were few cranes of any size seen outside the major towns, and cranes often travelled significant distances to undertake minor lifts. It was not unheard of for a crane to travel for a day for a half-hour job.
The Franna crane came to the market in the early 1980s and, like the tractor crane, it was an articulated machine. Where it differed is that it used a truck drivetrain that gave it greater mobility, and it positioned the cab on the front chassis section, under the boom, providing the operator with a vastly superior view of the load when lifting, as well as providing a better view for road travel. In final production form, it became a four-wheel-drive machine.
Even though Franna was an unknown brand at the time, it was the right crane for the era and over time it gained market ascendancy. However it was not without competitors – initially the tractor crane, and then tractor crane manufacturer Linmac, which came up with its own articulated high speed pick-and-carry crane, the AWD. When Linmac failed, Forward Engineering took over the design, and by the time that Forward Engineering ceased manufacture of cranes, DRA Engineering had a crane on offer, although it was not actively sold for a number of years.
The early times of the Franna crane gave no indication of its current success: it was not until the 2002/2003 financial year that annual sales were consistently above 100 units a year. Prior to that, sales fluctuated widely, from a low of 30 units in 1991/92 to a high of 150 in 1997/98.
The first Franna had a capacity of 8t capacity, and tractor cranes of the same era had similar capacity. The capacity of the Franna was increased to 10t, and then 12t. At the same time that the 12t upgrade of the original was launched, a higher capacity 16t model was introduced. In these capacities there were both high-speed (AT) and lower specification (MAC) models, with the less mobile units aimed at the site crane market. Initially sales of the 12t and 16t machines were roughly comparable. In the intervening years these machines have been upgraded to 15t and 20t respectively, and the market now shows a distinct preference for the 20t capacity high speed model, with the only lower mobility machine produced today being the 15t capacity UC-15.
A 25t capacity machine has been added to the range, and while sales of this machine were initially barely sufficient to justify its existence, it now has consistent healthy sales. This machine was introduced as a lower mobility machine, but its road speed is now comparable to most truck cranes on the market.
These trends suggest Australia wants a high speed pick-and-carry taxi crane. This model can travel on the road at a similar speed to an all terrain or truck crane, be ready to work virtually as soon as it gets to site (as it does not need outriggers), and can carry a sizeable load rather than set up in multiple positions and double-handle the load.
This appeal has reached the level where, despite Terex Franna continually increasing production, demand shows no sign of abating. Late model used cranes can sell for better than new prices, older cranes sell for more than they originally cost, and some owners are placing orders for cranes for which they do not have an immediate need, in the knowledge that they can sell on without a loss. Chris Logan of Gleason Cranes says that prices of used Frannas are unsustainably high, and feels that a softening of economic conditions and the availability of alternate machines could see normal values restored in 12–24 months.
What has evolved is the perfect climate for others to enter the market. Economies of scale, and the buying power of the Terex group, make it virtually impossible for another Australian manufacturer to become a volume seller unless they make a leap in design. The only realistic way of entering the volume market is to have cranes built in another country, where costs are lower and the facilities exist for volume manufacture. Two companies have taken this path, and there have been rumours of a third party investigating this course of action, but it is unlikely that there is room for three new volume manufacturers, particularly if the market declines in the current economic climate. There are many who at present would not consider a pick and carry crane other than a Franna, so any inroads by the newcomers will be hard-won.
Fortsetzung im nächsten Posting
Mal was ganz Anderes: Marion Walking Dragline aus Constructor (Holzbaukasten)
Dieser Post wurde am 12.06.2013 um 15:27 Uhr von Menzitowoc editiert.