What is a mini-crane? In Japan the definition is clear: it is anything under 5t capacity, as that is the threshold for requiring an operator’s licence. Hence 4.9t is a popular class in Japan and the term mini-crane is in common currency.
But the term “mini” is also used for not quite so small rough terrain cranes, the 10t or 20t models, though here the prefix “city crane” or “city class” has taken over.
In Japan, where the mini concept is most enthusiastically embraced, the market for crawler cranes of 3t capacity and under was about 1,200 units three years ago. In the year to 31 March 1999, about 700 were sold, reflecting the general decline in the economy.
There are various applications for them. They are used for underground work, subway construction and the like, or anywhere that space is constrained. They have also been placed on top of a structure to hoist material up instead of using a big mobile with a long boom to do all the lifting. Often, the big crane is needed not because of the weight of the load but for the reach that it offers. Yet the cheaper option may be to hire the long reach machine for a single lift only, just to raise the mini onto the building, and then use the mini for the donkey work of hoisting materials.
Maeda, part of the Maeda Corporation, one of Japan’s biggest general contractors, produces a small range of mini-crawlers ranging from 1t to 3t capacities which it markets under generic name of “crab cranes” on account of the outriggers resembling crabs’ legs. Maeda reckons that it is the biggest manufacturer of this type of mini-crawler, claiming an average market share of 30% in Japan, reaching 60% with certain models, in competition with Tadano, Furukawa Unic and Toa.
At the top of the range is the MC-355C, which lifts 3.5t and has a five-section boom reaching 12m. The range also includes the MC-274C (2.7t, four-section boom), the MC-275C (2.7t, five-section boom) and the MC-205C (2t, five-section boom).
New this year is the smallest of the range, the radio-controlled 1t-capacity MC-104CW, which has a reach of just over 5m yet folds away into a unit less than 2m long, 600mm wide and 1.3m high. Reducing the vehicle width was Maeda’s response to “client needs for more compact crawler cranes usable in narrow spaces for transporting tombstones and for engaging in plant transplanting in gardens”.
According to the manufacturer, this is the first time that a pentagonal fully-automatic four-section boom has been used on this class of crawler crane.
Another new model is the MC-305CW, a modified version of the 2.9t-capacity MC-355C. The wire extension has been put inside the boom for protection, sliding outriggers have been lengthened for extra stability, and a new operator’s seat has been fitted for comfort. Maeda’s target is to sell 200 units a year of this model in Japan.
Komatsu, with whom Maeda works closely in crane development, achieved CE approval for its 4.9t-capacity LC 755 mini-crawler earlier this year and it is being test marketed by Komatsu Europe in Germany.
Komatsu has no plans to market its mini-RTs in Europe, though, despite exhibiting a 4.9t-capacity LT 300 at the Bauma show in Germany last year to test the water.
Maeda’s new models were on show at Japan’s Conet exhibition, held in Tokyo in July, where other exhibits included Furukawa Unic’s UR-A500CL, a mini crawler that lifts 3t at 3.4m.
Also on show was the CCH 30T Pick Ace, a 2.93t-capacity crawler from IHI with a 10m telescoping boom. The CCH 30T’s key feature is that it has zero tail swing and so can work within the width of its 1.74m tracks.
This machine has the body of an IHI mini-excavator and the crane of a Tadano truck loader, thus keeping costs down by using standard components. It was produced specifically in response to a request from AGD, IHI’s UK based European dealer. AGD is one of Europe’s keener promoters of the mini concept. It claims to have launched mini-cranes into the UK with the 4.9t-capacity IHI crawler CCH 50T, selling its first model to contractor J Murphy in 1990.
AGD has 40 minis in its rental fleet of crawlers: 15 units of the CCH 50T, 10 recently acquired CCH 30Ts and 15 of Kato’s 3t-capacity KC30 city crane. The Kato is a mini-crawler dating back to 1990.
AGD has a further 15 units of the IHI three tonner in stock for sale, though there buyers have been slow to come forward. “It is predominantly a rental market,” says AGD sales director Robert Law.
Law says that the market for mini-cranes in Europe remains immature. “There are hundreds of applications for them outside of civil engineering that haven’t really been explored yet,” he says. “It is only really in London where they have been used on a regular basis.” Similar in concept to the IHI crane is Aichi’s FR-300, which has a lifting capacity of 2.95t. Though its boom is only 8.6m long at maximum, compared to the CCH 30T’s 10m, it has a noticeably better load chart. Three units were shipped to Europe last year and the crane was exhibited at Bauma ’98 in Germany. However, without significant modification, it could not secure the CE certification necessary for Europe and all three units were returned to Japan. Though it is not available in Europe, the FR 300 is now being promoted in North America and was exhibited at Conexpo this year.
A notable non-Japanese specialist manufacturer in this segment is Sandhurst Manufacturing Company (SMC) of the UK. SMC does not like the label mini for its cranes, preferring to call them compact, but whatever the label, SMC’s range of Starlifter crawlers come firmly into the category under discussion.
New this year from SMC is the 3t-capacity CX-3T, which supercedes the 2.2t CX 220 model. The two-stage telescopic boom extends to give a 6m height under hook. Rigged on three falls of rope, it has a 12m drop with a 36m drop on a single fall.
A more significant development for SMC this year, however, is that it has finally broken into the fleet of a major rental company, with Ainscough Group taking its first Starlifter. Ainscough opted for a CX 800, which has a maximum capacity of 8t with stabilisers deployed and a 13m height under hook. Its footprint is 3.48m by 3.48m. “We have been inundated with enquiries for this machine,” says Ainscough director James Ainscough.
The third model in the Starlifter range is the 1t-capacity CX 100.
AGD believes that the relative success of the CX 800 in the UK is due to lack of competition. For this reason it has asked IHI to develop an 8t crawler with which to take on the Starlifter.
Other developments on the mini mobile side include Kato launching into Europe its 10t-capacity city crane, the CR-100. This move follows the success that the 25t version, the CR-250, has had, particularly in the UK. In Japan more than 2,800 units of the 10t machine have already been sold. First in line to buy the CR-100 in Europe were Bernard Hunter and Ainscough Group in the UK and Trackline and Crane Hire in the Republic of Ireland.
