There are many types of mobile crane that can do a good job serving in a harbour setting, from a little old Jones Iron Fairy to a big Manitowoc or Kobelco crawler. But the class of crane specifically known as mobile harbour cranes, or sometimes harbour mobiles, has only three main players on the international stage. These are the Demag Gottwald HMK line, the Liebherr Nenzing LHM series, and Fantuzzi Reggiane’s cranes. Broadly speaking, the market breaks down roughly into 40% Demag, 40% Liebherr and 20% Reggiane.

Beyond these, there are cranes that are based on standard production duty-cycle cranes that have been specifically adapted for customers in the docks and harbours sector. The most visible alteration made to the standard cranes is the elevated cabin, enabling the operator to see into the hold of a ship. This type of machine is also typically seen in scrap yards. Sennebogen says that its Port Line, which has achieved some notable sales since being introduced two years ago, should be seen as a purpose-built harbour mobile, however, and not as an adapted construction crane.

While none of these types of crane can compete with the big permanently installed ship-to-shore cranes, there will always be a market for the mobiles.

Sticking with the traditional harbour mobiles for the moment, Gottwald has generally been market leader, with more than 750 units sold to more than 70 countries. The cranes rely on a diesel-electric system for low operating and maintenance cost, and a long service life.

Sale successes

Liebherr says that mobile harbour cranes have increasingly become accepted as a solution for ship-to-shore container handling. ‘The increasing demand in the last five years is proving this trend,’ says Liebherr’s Berthold Leopold. Benefits of harbour mobiles include the fact that no infrastructure is required, they are transportable and they have a high resale value.

Gottwald says that over the next couple of years it expects the market for mobile harbour cranes to grow further. In the first seven months of 2001 Gottwald received orders for 36 mobile harbour cranes with capacities from 63t to 120t. Most of these are to be used for container handling, although the prime advantage of harbour mobiles over other types of dockside lifting equipment is their versatility – they are just as suitable for moving general cargo and bulk materials. Seven of Gottwald’s orders are for four-rope cranes for bulk handling. The market for mobile harbour cranes with four ropes is also expected to grow, Gottwald says.

Gottwald’s best seller this year is the HMK 300E with 13 units shipped or on order. Introduced to the market last year, the HMK 300E is the most recent addition to the Gottwald HMK product line. This model is based on the HMK 280E – ‘the most successful mobile harbour crane in the world’, Gottwald claims – but has a stronger load chart. The redesigned successor can handle five fully loaded standard 40ft containers in the 13th row of a panamax vessel without repositioning the crane.

One satisfied owner of an HMK 300E is Agunsa in San Antonio, Chile. Agunsa uses the crane for ship-to shore operations, equipped with a twin-lift spreader capable of handling two 20ft containers in one lift. Agunsa has achieved an average hourly handling rate of 22 units for single container handling and 28 units per hour for twinlift container handling. Peak rates are 47 units per hour.

Other HMK 300Es have also been shipped to customers in Colombia, Finland, Italy, Korea, Turkey, USA, Venezuela, Vietnam and Australia.

Liebherr believes that the total worldwide market for harbour mobiles in 2001 will be between 100 and 120 units. Its own sales target for the year is 45 units. ‘So far, it looks like we will exceed this figure,’ says Leopold. By mid-September 31 units had been delivered, including only the machines produced this year, with another 11 for delivery before year-end.

Orders of note for Liebherr include an LHM 100 to Kitimat in British Columbia, Canada, which is the company’s first harbour mobile on the west coast of North America. It has also sent a total of seven LHM 250s to two customers in Africa.

Liebherr says that it brings to its LHM cranes its years of experience building ship cranes for the most hostile marine environment. It claims that although its prices are higher than other cranes, over the 20 to 25 year design life the crane’s whole life cost is lower because of its modern design.

Liebherr says that its harbour mobiles are the only ones to have a zero inner turning radius, and therefore complete manoeuvrability in any direction, allowing any kind of travelling motion, including crabbing to either side. This is achieved by the new undercarriage system carrying its axle sets below the mainframe structure.

The multiple axle sets of the undercarriage results in a typical axle loading of less than half that of competing products, Liebherr claims. The lower axle loading means less wear and tear on the main frame and hence a lighter structure, which in turn reduces structural stresses on the dock.

The hydraulic drive system of the Liebherr LHM cranes allows hoisting, slewing and luffing to be carried out simultaneously. And according to Liebherr the required moment of inertia of hydraulic components is 50 times less than that with electrical components. With acceleration and deceleration being quicker on hydraulic cranes, Liebherr claims, the cargo handling is faster and more efficient.