RT resurgence

Used as a support for larger equipment, rough terrains (RTs) are used in applications such as general construction, material handling, steel erection, low-rise apartment construction and refinery refurbishment and maintenance. This crane type has a region-focused interest in North America, the Middle East and Japan, compared to the wider appeal of all terrain cranes.

RTs are currently enjoying a resurgence with many manufacturers investing in new models and even entire series. The biggest news over the last few months came from manufacturing giant Liebherr, with the introduction of the company’s first RT line in over 20 years.

The first models to be released – making their debut at ConExpo, Las Vegas, this month – are the 100 tonne LRT 1100-2.1 and the 90 tonne LRT 1090-2.1.

Dr Ulrich Hamme, managing director, construction and development at Liebherr-Werk Ehingen, says, “The new LRT cranes stand for safe, simple, powerful and economical. These two crane types should meet all requirements on RT cranes in their class; from off-road pick and carry RT cranes, up to flexible industrial cranes in large industrial plants.”

The decision to re-enter the RT market is said by Liebherr to be because of continuous customer requests over the company’s two-decade absence.

The 100 tonne LRT 1100-2.1 has a 50 metre telescopic boom with a ‘Telematik’ telescope system. Liebherr says that the lifting capacity of this larger LRT crane is approximately 15 percent greater than that of the 90 tonne version. The LRT 1090-2.1 has a 47 m telescopic boom that has a two-stage hydraulic cylinder with mechanical rope extension.

At the end of January, USA-based All group ordered 15 units of the LRT 1090-2.1.

The RT90 from Terex was unveiled at Bauma, Munich, in 2016, said by the manufacturer to offer “unprecedented capabilities in a rough terrain crane”. The 90 tonne capacity model has the IC-1 control system and uses high strength steel giving great performance while reducing weight.

Suresh Natarajan, director of rough terrain product management at Terex, says, “The five section, full power boom of the crane stretches 47 m for long reach applications. By using proven standard components and by incorporating lessons learnt from the past, the design has focused sharply on reliability.”

Higher performance

For the Japanese market, Kobelco’s latest model is the MK650 – released in 2014 – developed by combining the company’s knowledge and experience on attachment and upper structure technology for crawler cranes and undercarriage technology for wheeled cranes.

The maximum lifting capacity of the MK650 is 65 tonnes at 3 m and a boom length of 5.6 to 33 m.

Italy-based manufacturer Locatelli Cranes is specialised in the production of RT cranes. The company describes its line as “strong, reliable and maneuverable”, ranging from 12.5 to 80 tonnes capacity.

Locatelli is launching ‘light duty’, ‘medium duty’ and ‘heavy duty’ versions of its RTs so it can meet all application needs. It will also be revealing a range later this year with new designs, higher performances, customized solutions and updated safety equipment.

China-based manufacturer Zoomlion is launching a new generation of ZRT rough terrain products: the ZRT500, ZRT700 and ZRT900.

Ken Zhou, product manager mobile crane at Zoomlion, says, “We will soon carry out the scale-production of the new product ZRT900, which has stronger lifting performance, larger telescopic length of main boom and adapts to the desert region in the Middle East.”