If there is one word that defines the development of loader cranes it is versatility. No longer are they restricted to loading and unloading materials. Developments such as electro-hydraulic control systems and new grabbing accessories have enabled loader cranes to become versatile manipulators capable of a wider range of tasks in both static handling and transport logistics.
Jonsered, for example, says that for years it was known as a manufacturer of timber cranes, but now it has developed a line of cranes for the recycling business. Ranging from 5tm to 33tm capacities and 6m to 16m in hydraulic outreaches, there are cranes offered for both intermittent operations – where power, precision and safety are paramount, for example when handling valuable loads or hazardous waste – and for continuous loading – where speed, durability and productivity are more important. Three additions to this range have been made this year: the J520, J720 and J1220 for static mounting and the J1820, which is available for both static and mobile mounting. The J520, rated at 5tm, is at the bottom end of Jonsered’s range, while the J1820 is mid-range.
Palfinger’s latest grabbing crane, designed for arduous working conditions, is the 8.5tm-rated Epsilon 93A. This unit, lifting more than 1t at 8.3m and 3t at 3m, is described by Palfinger as “the ideal grabbing crane for both long reach and close-to-column work”. High pressure and return filters are fitted as standard and load holding valves are fitted on the main, outer and extension booms. It also features a return oil system to further enhance operating speeds. Hydraulic rams are mounted on the top side of the boom to protect them from damage during operation.
The Atlas 60.1 crane has proved its worth in a municipal tree planting and landscaping operation on the B213 federal highway in Germany. The 6tm-rated truck-mounted crane, with dual hydraulic extensions and a 6.5m hydraulic outreach, was used for unloading and planting trees and distributing topsoil and mulch. Atlas says that its 85.1 model, rated at 8.5tm, is another versatile tool, thanks to a comprehensive range of tools and accessories that can be used on the end of the jib.
The jib and extensions have a hexagonal profile and are designed to withstand severe torsional loads. The crane column slews in low friction, high performance bearings. This means higher efficiency and reduced strain on the slewing gear during normal operation, Atlas says.
More and more loader crane manufacturers are offering as a feature the option of increased power at the cost of a slower operating speed.
This added-power function, which is designed to enable the crane to continue working in what would otherwise be an overload condition without having to bring the crane back to the column, is given different names by different manufacturers. Hiab calls it LOS (load operated speed), Fassi has XB, Autogru PM has Plus, and Fratelli Ferrari launched its PB (for power boost) feature at the Samoter show in Italy in March (Italian fashions May99, p15).
Atlas this year unveiled its LMplus technology on the 330.1V crane, which enables lifting capacity to be increased at reduced working speeds. This crane also combines an LS valve with a variable displacement pump to allow the operator to carry out several functions at once, irrespective of the load.
The valve permits a variable oil delivery rate and a proportional response to control lever movement. The variable displacement pump delivers precisely the right amount of oil for every movement made by the operator. The benefits, Atlas says, are lower hydraulic fluid temperatures, less noise, and lower fuel consumption.
Palfinger offers HPLS (high power lifting system) as standard on its models PK 14600, PK 17000, PK 21000 and PK 27000. These models also feature Paltronic, radio remote control and an oil cooler. Paltronic is a fully automatic monitoring system of the electronic controls. The PK 27000 also has a load sensing system which improves operation and control with a variable hydraulic pump.
Some power boost systems, such as Ferrari’s, are triggered by the operator flicking a switch when necessary. Effer’s FPI is automatic. It works entirely by hydraulics and kicks in automatically when the load applied to the crane generates a pressure inside the inner boom cylinder that is higher than the pressure at which the FPI is set. The FPI device starts working by cutting part of the oil flow down to a pre-set value, Effer explains.
The operator can tell this has happened because the crane speed slows, but as the working pressure in the hydraulic circuit is increased, the crane can lift heavier loads. To return to the normal working speed the load moment must be reduced by bringing the crane back towards the column. All cranes fitted with the FPI device are also fitted with an Effer overload safety device.
Hiab’s power-boosting LOS is featured on some of the cranes that it launched earlier this year, namely the 900 E, 400 E, and 220 C. These cranes also have the electronic control and security system SPACE, V91 control valve for smooth operation and the advanced remote control CombiDrive as standard.
These three cranes are among five truck-mounted heavyweight cranes, designated C series and E series. The C series uses an inner boom link, the E models use an inner and outer boom link system. The 200 C is available with four different boom systems, giving a maximum reach of between 8m and 14.1m, with lifting capacities of up to 7t next to the column. The three E series cranes are for heavier lifting. The 360 E has eight boom sections, reaching 21.4m where it can lift 760kg. Maximum capacity at the column is 14.6t. The 400 E is designed for bulkier loads and, depending on the number of hydraulic extensions selected, lift capacity varies from 15.7t at 2m reach to 890kg at 21.4m.
The 900 E is Hiab’s truck-mounted flagship. Six extensions provide an outreach of 16.4m, where it can lift 4t. At 2.5m it can lift nearly 25t. Fitting a jib to the 900 E-8 version gives a reach of 31.7m, at which distance it can lift 400kg.
Hiab has also introduced a new series of lightweight stiff boom cranes, the four-model T series, comprising the 008 T (which weighs just 125kg), 013 T, 017 T and 026 T. Purchasers can specify manual or hydraulic extensions.
The larger two models are fitted with Hiab’s electro-hydraulic Boss system (basic overload safety system). The 026 T is designed for the heaviest loads carried on light commercial vehicles and can lift 1900kg close in and 550kg at maximum hydraulic outreach of 4.6m.
