Modernisation of crane scales
EN ISO 13849 ensures maximum functional safety
Since 1 January 2012, EN ISO 13849 has been the only standard in force for control functions of relevance to safety. All new cranes and major modernisation projects have had to be designed in line with this standard since this date. Put simply, this standard stipulates that through an appropriate choice of hardware and software, overload protection in cranes must be designed such that the failure of one component in the measuring chain does not result in subsequent overload events not being detected or reported.
Reliable overload control and unbalance load detection that is state-of-the-art
By innovatively combining our proven DISOBOX® Plus and DISOMAT® Tersus weighing electronics, overload protection in accordance with EN ISO 13849 can be realised for up to two crane hoists.
In many cases, the weighing mechanics in the crane can even continue to be used unchanged.
This addition and the new safety functions bring main contractors and end users significant benefits in terms of investment, diversity of parts, standardisation, training and spare part management.
Reliable collective load calculation to optimise crane maintenance intervals
The DISOMAT® Tersus weighing terminal is equipped with a so-called collective load memory. The maintenance staff can read the load history recorded automatically during crane operation from the DISOMAT® Tersus memory at regular intervals.
This additional function enables Schenck Process weighing electronics to greatly optimise maintenance intervals of the crane, resulting in costs savings and improved productivity through increased availability – without any compromise in safety!
High-precision weighing as the basis for optimum material balancing and process control
The various crane scales in the steelworks play a key role in ensuring a safe, efficient and economic production process. High weighing accuracy is important for the precise balancing of all incoming materials and end products. Essentially, this is determined by the weighing mechanics. However, modern weighing electronics also help to achieve optimum accuracy: for example, in upper sheave-block weighing systems, the DISOMAT® Tersus provides a function for compensating the weight of the crane ropes, meaning that the scales always display the same weight regardless of the lifting height of the spreader beam.
Preventive maintenance and diagnosis functions for maximum availability
Heavy-duty cranes used in steel production need very high levels of availability – downtimes and maintenance times must be kept to a minimum.
Schenck Process has satisfied these requirements in its modern DISOBOX® Plus and DISOMAT® Tersus weighing electronics with vastly extended diagnosis functions. Nowadays, our equipment in the control room on the ground doesn’t just display the current weight on the scales, but also monitors the individual weights and temperatures of every single load cell. All important adjustment and setting work can also be managed here. This improves not just the availability and reliability of the crane scales, but also the safety of the maintenance staff.
Ultramodern interfaces for flexible communication with the PLC control system
Over the last few years, many steelworks have fully modernised their process control systems. Compared with them, the weighing electronics in many crane scales are often so out-of-date that the modern functions cannot be used.
To solve this problem, simply upgrading to DISOBOX® Plus and DISOMAT® Tersus provides Profibus DP, DeviceNet, Ethernet and Profinet interfaces. All the scales’ important operating data can therefore be transferred to the customer control system where it can be processed in line with current industrial standards.
What’s more, our wireless data transmission options for communication between the crane and control room are particularly useful for such crane scales.