Atonsu-Agogo (Ash), June 28, GNA – Some researchers at the Department of Industrial Art, Kwame Nkrumah University of Science and Technology (KNUST), are bringing their expertise to bear to improve local crucible production.
The objective is to help transform the industry for the better by assisting local crucible producers, especially those at Atonsu-Agogo in the Asokwa Municipality, to embrace good practices along the value chain.
“Crucibles produced from Atonsu-Agogo are of great importance to the local jewellery industry in Kumasi for smelting and refining of metals, and yet less is known on how they are manufactured,” Dr. Samuel Baah Kissi, a Lecturer at the Department has said.
Currently, the researchers are providing the workers with the needed technical and scientific assistance under a project dubbed ‘Improving Local Crucible Production for Metal Casting’.
“The agenda is to unleash the industry’s broad development prospects in terms of job and wealth creation,” Dr. Baah Kissi told the Ghana News Agency (GNA), on the sidelines of a visit by the researchers to one of the crucible processing sites at Atonsu-Agogo.
He argued that crucibles produced locally ought to meet acceptable standards in terms of quality.
He said, research and observations conducted by a team of researchers from the Industrial Art Department revealed that “the locally manufactured crucibles which are being used by the local jewelers and goldsmiths as well as used by the casting industries, are not durable as the foreign or imported crucibles”.
“The crucibles, when compared with imported ones, which are expensive and difficult or sometimes impossible to obtain locally, have a very short life span,” he told the GNA.
The study aimed at identifying the right materials to be used in the production of local crucibles at Atonsu-Agogo, and also to work on the lifespan of the ones being produced presently in terms of their durability and performance.
Dr. Baah Kissi said that the research investigated and experimented with other materials such as clay additives to improve the life span of local crucibles.
The researchers also documented the working processes, as well as that practiced at Atonsu-Agogo in producing local crucibles.
In their recommendations, the researchers proposed that the proportion of graphite to clay, borax to clay and grog to clay as used in this research must be adhered to, and borax flux should not be used on melts when clay-graphite crucibles are used.
They also recommended that clay-borax crucibles should be used for metal refining.
Dr. Peggy Ama Fenning, a Senior Lecturer, and member of the research team, said experimental research was used to derive the suitable materials for the crucible composition by varying the materials to study their response to intense melting conditions.
“Experiments were conducted to determine the problem with the composition used by the people of Atonsu -Agogo in the manufacture of their local crucibles.
“Experiments were also conducted to obtain an ultimate solution to extend the life span of these crucibles and to make them stronger and ideal for any metal melting temperature as far as jewellery production is concerned,” she told GNA.
According to the researcher, since clay was the primary material used to produce crucibles by the people of Atonsu-Agogo, it had to be processed through some stages to get it ready for the manufacturing process.
A concept note underpinning the research says gold and silver are precious metals and as such, crucibles which will be used in the melting of these precious metals should be handled with special attention.
The crucibles which will be used in casting gold alloys, for instance, must be kept clean by covering the inside of the crucibles with moistened strips of heat resistant material and relining them for reuse.
According to the researchers, three crucibles with different compositions were used in their experiment, and all subjected to identical conditions.
The various compositions yielded contrasting results, they observed.
The experiments indicated that the local crucibles from Atonsu-Agogo could not withstand thermal-shock.
With the technical expertise provided by the researchers, crucible compositions made up of clay-borax, clay-grog, and clay-graphite were found to have improved the local crucibles.
Tests were done on the crucibles’ resistance to thermal-shock, tendency of metal not to oxidize, melting test and crucible re-usability. One each was taken from each composition for the test.
“From the analysis, we can boldly say that this experiment is a successful one indeed.
“All the crucibles were able to survive the thermal-shock test and the slagging test, which is a great achievement,” the researchers concluded.
GNA