Tower crane manufacturers are looking for niche markets
By Heinz-Gert Kessel16 September 2009
In these stormy times of a woldwide economic slowdown, one area where manufacturers are looking for business is niche markets with specially adapted cranes. Heinz-Gert Kessel reports
For years Denmark-based tower crane manufacturer Krøll has been establishing a growing market share in custom-made wharf tower cranes supplied for shipyards in the far east. This year Krøll will ship three K3000 and one K3500 models to Korean shipyard DSME, which already operates a number of Krøll units.
At the end of 2009 six K3000, one K3500, one K4000 and two of the large K5000 type will be working for DSME. The new K3000 can lift up to 100 tonnes at 28.5 m radius. At 90 m radius capacity is still 23 tonnes.
The crane has one trolley offering two reeving possibilities. With 10 line falls 40 to 100 tonnes can be raised at a speed of 12 to 22 m/min. For light loads up to 20 tonnes a two fall line operation is available with speed up to 110 m/min.
The K3000 cranes for DSME travel on 12 m and 16 m wide portal with an underhook height of 69 m and 75 m based on a 6.4 x 6.4 m tower system. Thanks to the sophisticated design, maximum erection weight of the crane components was reduced to 32 tonnes.
The latest addition to the Krøll product line is the K1000. Two units were erected at the Samsung shipyard in Korea at the beginning of 2009. Using the well proven M40 3.6 x 3.6 m mast system with external climbing cage, the cranes were jacked to 70 m and 60 m underhook height. Both cranes are based on a specially designed 9.5 m wide stationary portal with height-adjustable pyramids.
To move the Krøll cranes on site while erected, self propelled units can be used to drive under the portal, lift up the complete crane and move it. They can also be picked up by a floating crane at a wharf and and relocated. To make this popular movement by floating cranes easier all new cranes for DSME and Samsung have special lifting lugs at the tower head.
The new K1000s have 90 m jib and lift 40 tonnes to 20.1 m radius, while the tip load is 5 tonnes. Light loads up to 10 tonnes can be lifted on two falls, while maximum capacity needs eight falls. Fastest hoisting speed is 150 m/min.
Optional is a double trolley arrangement that increases the tip load to 7 tonnes. In contrast to the former Krøll heavy lift models, the new K1000's winch platform is no longer on the jib head section but on the counterjib, reducing the dead weight of the jib. In 2010 Krøll will install a K1200 and a K2500 at the Samsung shipyard in Korea. Each crane will have two independent movable trolley systems and a dual hoisting winch to turn large prefabricated ship sections.
Ultra high rise
After launching what is claimed to be the biggest luffing jib tower crane in the word, the M2480D, (IC Feb 2009, page 31), heavy duty crane specialist Favelle Favco designed another interesting luffer. Also for large scale construction projects, the M860D lifts 96 tonnes at 10 m radius in only three fall operation. It offers an outreach of 70 m where 7 tonnes can be lifted. On a single fall of rope up to 32 tonnes can be lifted by the main hoist.
The 750 m winch capacity making the crane suitable for ultra high rise construction projects. An auxiliary hoist for loads up to 12 tonnes is an option. Simon Marr of Australian company Marr's Contracting, owner of M2480D and other big Favcos, believes it to be the fastest hoist in the world, with a line speed of 260 m/min.
Like the M2480D, ballast plates are stored lying down inside the back of the machinery split-deck. Tail radius is restricted to 9.24 m, a benefit on construction sites where space is restricted. The 3 x 3 m monoblock tower system is for speedy erection to a free standing tower height up to 64 m. This feature gives the new M860D the opportunity to find a ready market in the international power plant construction programme.
Marr's has bought three M860Ds to be used on special undercarriages for construction of a jetty at Bown in Queensland, Australia. They take on the work formerly only possible with crawler cranes, which needed an expensive separate track way to move on as construction progresses. A real benefit when working at the coast is that the tower cranes can keep working at a wind speed of 20 m/s, while the crawlers have to stop work at 9 m/s.
In addition, electric versions of the usually diesel powered Favelle Favco tower cranes are entering the European market. Two MK380 and one MK440 have been sold as internal climbing cranes for the prestigious Pinnacle Tower project in London. Aside from the electric drives supplied by Krøll in Denmark, these cranes have other unique special features. All four luffing jib cranes, for example, have hydraulically lockable boom buffers to leave the cranes slew locked out of service due the congested site.
German crane manufacturer Jost is also looking for niches in export markets, for example, in Australia, where European crane design is going to play an increasingly important role. To address the specific customer requirements in a market formerly dominated by high speed diesel cranes, Franc Jost combines its successful luffing jib crane concept with a new hoisting drive design.
The hoisting winch of the JL616.32 for Australia is driven with two side-mounted 75 kw frequency regulated drive units providing a total capacity of 150 kw for the crane lifting 32 tonnes in four line reeving mode and 16 tonnes in two fall operation. Drum capacity is 1,060 m. Thanks to the dual drive, even if one motor brakes down, the crane can keep working at half speed.
In addition, spare parts stocking is simplified as the luffing winch is another of the 75 kW drives. As soon as the sidewalk platform is disconnected the complete counterjib, including winch platform, can be transported inside a standard container. A further JL416.24 with 12 tonnes capacity on one line fall and 24 tonnes on two falls has been manufactured for Korea. It also has the dual hoisting drive system. In this case two 90 kw frequency regulated drives enable 400 m under hook height and a capacity of 24 tonnes.
Jost Cranes is designing a new hoist winch for the JL616.50 luffer with a capacity of 50 tonnes in two-fall operation. On a single part line 25 tonnes can be lifted to 800 m. On its first job site the crane will be used as an internal climbing crane.
Larger power stations means bigger cranes. In China the FZQ1380 luffing jib climbing crane designed in 2001 by the Shandong Fenghui Equipment Technology Company, is suitable as the main lifting equipment for 300 to 600 MW power pant construction but is too small for the growing number of 1,000 to 1,300 MW plants. As a result it is no longer produced and has been substituted by the 75 tonne capacity FZQ1650 and, more recently, by the large FZQ2200 with 100 tonne capacity.
In contrast to the FZQ1650 a monoblock tower system cannot be used with the new crane.
Regarding transport and rigging problems associated with 4.2 x 4.2 m cross section towers, with help from the Harbin Industry University, a way was found to split down the tower elements in K-shaped panels und tubular core sections, which are slug-bolted together on the job site before being lifted by an auxiliary winch to the front opening of an external climbing frame. It means that pre-rigging of the tower is done under safer conditions at ground level.
The auxiliary 10 tonne erection allows the boom to be left at maximum radius during the complete climbing phase which makes for a safer climbing procedure. Like on the old Linden 8000 tower system the mast sections are connected by clamps surrounding the mast joints. A further benefit is the cross-shaped stationary undercarriage with large pontoons at the end of its outriggers.
For simple erection the inverted u-shaped ballast blocks are hung over the outriggers. No expensive conventional footing block with anchorage is required and the crane can be even installed above crossing pipes that lead to the boiler block.
For best performance there are stepless frequency regulated drives, planetary reducers inside Lebus winches, video surveillance, real-time monitoring and self diagnostic black box systems.
Walk-in electrical cabinets and an elevator running inside the tower are design features. The sophisticated heavy luffing jib crane is not only developed for its domestic market and it has CE certification.
Target export markets are East Europe, India and Indonesia. An FZQ2200 supplied by CITIC International Contracting Inc. was erected at the Campinas C Thermal Power Plant Phase II Project in Brazil in March 2009.
After Potain launched the MD1100 in 2008 a number of Chinese crane manufacturers adapted some of the major structural design principles for new crane models in this capacity class. One of the first was Zoomlion with the D1100 presented to the public in November 2008.
This year further competitors have followed, for example, Sichuan Jincheng Construction Machinery Co. It has installed its all new M900 with 50 tonne capacity and 70 m jib with 9.1 tonne tip load at a power station project in Inner Mongolia.
Yongmao delivered its first ST80/116 for a shipyard on travelling portal base with a capacity of 40 tonnes and a tip load of 11.6 tonnes at 80 m radius. The biggest crane so far in the new line of large capacity saddle jib cranes is the 64 tonne capacity Yongmao ST80/238 with 23.8 tonnes at 80 m.
Yongmao sees potential for its CE certified large cranes to enter the European market for large construction projects like power stations.
Sichuan Construction Machinery Co. Ltd (SCM), with its M1200, developed a new crane in this capacity class with a capacity of 50 tonnes and, again, 11.5 tonnes at 80 m radius. In addition to SCM, Shenyang Sanyo Building Machinery Co.,Ltd (SYM) already has a reputation in large saddle jib crane construction.
For STX eight of the all new S1200K40 were manufactured as shipyard cranes with 40 tonnes capacity at 40 m radius and a tip load of 10.6 tonnes at 70 m. The cranes are specially weather proofed to work in harsh conditions.
In contrast to the Potain climbing system in the 1,000 tonne-metre class, complete tower sections are inserted through the opening of the climbing cage. It means that pre-rigging of the tower sections can be done more safely at ground level.