Operational aid devices for cranes are an established part of the lifting industry, aiming to ensure that an operator's job is easier and safer. The latest wave of products have become more customized to fit operators' specific needs, according to Frank Beardsley, technical director at Rayco Wylie, who says that devices such as the rated capacity indicator (RCI) are improving working conditions for crane operators around the world.
“A couple of years ago, for example, a customer may have thought it impossible to ask for and receive changes to the arrangement and content of displayed information on a recently installed RCI display while the technician was calibrating the system on a job-site. With a rated capacity indicator, this is now feasible.”
Pictured right, is the company's model i3000 rated capacity indicator, showing one version of several available screens in a standard graphic display supplied to a customer. The new screen was designed by the operator himself to provide crane information the way he wants to view it.
In this example, the operator sketched this screen, faxed it to the factory where it was programmed, e-mailed back to the on-site technician who downloaded the program into the RCI. Even the size of the numerals in different places was customized to suit the operator. In addition, the operator can switch back and forth from his screen to the other standard screen whenever he wants.
The Hirschmann Electronics Group (PAT) has extended its product range with the launch of the Maestro load moment indicator (LMI). This new system consists of a central unit, console and a range of accessories. The Maestro, according to PAT, provides a user-friendly and cost-effective modernization of old PAT LMIs. The Maestro was developed to modernize systems installed on boom trucks and hydraulic cranes to provide the latest technology on older cranes.
Retrofitting the Maestro, according to PAT, can be completed in just four steps. Firstly the central LMI unit is replaced with a compact unit and the original data and load chart information is then loaded into the central unit. After a sensor alignment through the console, the crane is ready for operation, without needing to be recalibrated. The original length and angle sensor, the anti-two-block switch and the electrical wiring from the old LMI system can be used. The Maestro also gives the option of incorporating wireless sensors into the LMI. This, claims Hirschmann, ensures that modernisation of an older PAT LMI with Maestro is significantly more cost-effective and faster than any other alternative.
Hirschmann has also developed a new wireless indicator for mobile cranes. The PRS 80 EZ is designed to monitor single or multiple sensor inputs, including combinations of load, anti-two block, boom angle and wind speed. The inputs are displayed on a large, backlit, graphic display, capable of displaying readings from up to seven sensors at one time. The operator can pre-set limits on load, wind speed and angle with audible and visual warning when the limits are reached. The PRS 80 EZ uses frequency hopping spread spectrum technology (FHSS) to ensure accurate and consistent reception of data. FHSS also provides additional protection against interference common to construction job sites. The system incorporates reliable and proven sensor technology with an operating range of up to 304 m, Hirschmann says.
Liebherr's new mobile cranes are fitted with the company's LICCON working area limitation system. The system, according to Liebherr, “unburdens the crane operator by controlling the working area limits, especially in situations where the handling of loads requires his full attention.”
Four different limitation functions are available; pulley head height limitation, radius limitation, slewing angle limitation and edge limitation. Each function can be activated independently or in conjunction with others so that a number of combinations can provide the operator with information at one time.
A better view
Cameras on cranes are becoming a common form of operator assistance device. Applications include giving the operator a view of the load in situations where it would otherwise be obscured by a building, or to allow the operator to monitor the winches.
In-crane camera system manufacturer Orlaco estimates that 25 to 30% (600 units) of mobile cranes in the Netherlands have a load view camera. Orlaco says that retrofit orders for cameras on mobiles in Sweden, Norway, Germany, Switzerland, Denmark, Belgium, France and Finland are carried out on a regular basis.
It is not just the retrofit market that Orlaco is succeeding in; the company says that Liebherr, Terex-Demag, Grove and Tadano Faun now offer Orlaco load view cameras as an option on new mobile cranes, while Spierings and Gottwald machines have them as standard.