Rhodium-free bushing solutions for the fiber glass industry
2010-04-16
The bushing is the device to form glass fibers by attenuation of liquid glass through a big number of nozzles. Bushings are usually made of Platinum alloys with up to 25% of Rhodium content to maintain mechanical stability during operation. Based on our different FKS material grades we have designed bushing solutions that can be made of pure Platinum without any disadvantage regarding process performance: a tremendous potential economic saving.
Stabilisation of Platinum by means of Rhodium is only one possibility to increase alloy performance, stabilisation by means of oxidic dispersions is a much more powerful option. Not only does this enable to reduce the Rhodium content of an alloy, it even means that Rhodium content can be completely removed.
Umicore’s FKS materials have meanwhile been successfully introduced to the fiber glass industry and could demonstrate their high performance in selected E-glass applications. By slightly adapting given standard alloy bushing designs to FKS material based Rhodium-free bushings, the desired bushing performance in the fiber attenuation process could at least be equalized – without any usage of Rhodium (except for some grams of Rhodium that are still needed in the thermocouples, of course).
Calculation example: Conversion of a given bushing design made of cast PtRh10 alloy (overall weight of about 4 kg, performing with a service time of 300 days) into a FKS Pt bushing solution performing at the same level. Taking into account the 5-year average prices of Platinum (1.257 USD/oz.) and Rhodium (4.197 USD/oz.), a total annual total cost reduction per bushing of about 10% can easily be achieved. This calculation does already take into account different fabrication cost for such bushings and a slightly increased weight of a Rhodium-free solution due to the higher physical density of Platinum compared with that of Rhodium.
How about your bushings ? Are you ready to save some money ?