Wireless Communication using RFID
IDENTIFY - AUTOMATE - OPTIMISE
Material tracking and logistics for steelworks and foundry plants
The key to an optimised production
The fiwa)group production management system
Practitioners and industry insiders are aware of the many possibilities for optimisation in the metalproducing and metalworking industry, on the way from raw materials to finished products. An excellent solution for process control, in which errors are largely ruled out, is provided by the fiwa)group with its modular production control system.
The system consists of four sub-systems interacting with each other:
1) Accurate weighing of furnaces, crucibles and ladles
(through patented heavy duty weighing kits)
2) Unequivocal identification
(by means of RFID transponders)
3) Local, non-contact read/write stations
(stationary and mobile devices)
4) iMES CC production management software
(fully integrable, modular MES system)
By using/integrating all four sub-systems in the production system, a seamless batch traceability is feasible in real time. For this to be obtained, all "players" must be equipped with RFID transponders. All information to and from the single stations of the production process is conveyed in a non-contact way. Thus, error sources in data transfer (reading or ambiguity errors) can be eliminated; in addition, there is also the option to log the entire material flow, thereby automating it. By linking the most important processes, a significant optimisation potential arises, for example, with regard to quality and material usage (exact recipe management/material quality), time (significant shortening of cycle times), energy costs (heating-up only when necessary) and also batch traceability (quality assurance).
Depending on the desired degree of automation, a customised solution is developed for the customer. In this respect, a big advantage is that the system can be expanded at any time to a fully integrated version complete with all features even when a minimal solution (e.g. traffic light control) is adopted.
A) Furnace weighing/ Raw materials handling
Both new furnace plants and existing furnaces can be easily equipped and retrofitted with the fiwa)group worldwide patented weighing kits. Weighing deviation is less than one kilogram per ten tonnes. The indication of the furnace and product weight is not only provided before, during and after filling, but this information is also always available over the emptying, heating-up or cleaning stages. As a result, any slag content in the product, deposit build-up, or product residues can be detected in the furnace. In alloys production it is possible to dose alloying additives very precisely, namely, with a degree of accuracy of less than 0.5% of the total product content.
B) Transport - Outgoing goods
Each transport crucible using RFID radio chip is uniquely identifiable (crucible ident.). The data determined during filling is transferred to the chip. The product data is available during the entire transport path.
C) Transport - Incoming goods
Upon the customer's goods receipt, the RFID chip automatically reads batch data in a non-contact way via antennas or hand-held terminals. Should any differences in terms of quantity, specifications or temperature be determined here, the customer can refuse acceptance of the goods even before production problems arise. If, for example, the temperature of the product is already at a critical level , the supplied crucibles can be immediately forwarded to then heating stations without wasting any time.
D) Reclining chair with scales
With a flawless product, transport crucibles are taken over by a reclining chair. At this station weighing is appropriately carried out again. Depending on production requirements, the raw product is delivered to so-called "(cating) ladles" that in most cases are conveyed by specially adapted forklifts e.g. to casting furnaces for further processing (alloying). Here, the crucible <-> ladle assignment occurs in the database.
E) From the forklift with ladle to the casting furnace
Here too RFID technology provides for the uniqueness of the ladle. All data is stored in the database (MES). Only the corresponding ID is stored on the chip (in the case of a crucible, the crucible ID). The forklift is provided with a read/write station which informs the forklift operator of the next bagging station, in addition to giving him the product data. Additionally, load cells are installed on the forklift between the ring gear and casting device; these ensure accurate and maintenance-free ladle weighing (0.02-0.03% of the product content). All occurring disturbances such as shear and side forces or impacts - caused by uneven terrain - are compensated.
F) Casting furnace - re-alloying
At this point, the alloy for the automated casting units is produced. The technical equipment of the casting furnace is similar to that of the furnace weighing system. To ensure the highest possible quality of the end product, accurate weighing and recipe management are essential.
G) From the forklift with ladle to the automated casting unit
At the casting furnace, the casting ladle is filled with an optimal amount depending on requirements, and can then feed several automated casting units in immediate succession. This is possible through the mobile ladle scales installed on the forklift. This way, the delivery of accurate quantities is guaranteed - re-weighing of the ladle contents or refilling at the casting furnace is no longer necessary. However, as also the temperature of the liquid raw material plays a major role on the last conveyor path before the actual casting process, prior to this a further heating station can be approached if necessary.
H) Automated casting unit
While emptying the ladle at the automated casting unit, a continuous weight display is available to the forklift operator; hence, the delivery of exact quantities is feasible. In addition, thanks to the RFID-based network, the approached automated casting unit will not accept any "wrong" ladles.
Advantages of the patented process
- Avoidance of sources of error
- Shorter distances
- Efficiency in and between the production stations
- Batch traceability
- Quality assurance
- Quality improvement
Scheme - wireless communication using RFID
The result of communication along all the stations involved is short paths and the delivery of the most accurate amounts - with virtually no error sources. This comprehensive production management system by the fiwa) group leads to increased efficiency in and between all manufacturing stations.
Anyone who, in the medium term, does not optimise the networking of all data sources important for the entire production (ERP, MES and automation), is likely to have significant competitive disadvantages. This is unanimously predicted by experts. Also the subject of "flexibility" becomes even more important with an increasing individualisation in production.