Graphite Crucibles Making Plant

1 Product Description: Graphite crucibles are extensively used in small and big industries for melting metals and alloys of copper, zinc, aluminum, tin, iron, nickel, gold, etc. These crucibles are mostly used for melting and casting smaller quantities of metals in small scale foundries.

2 Market Potential: Small scale melting of metals takes place in large repair and maintenance workshops. One notable example is the big repair workshop of the Ethio-Djibouti railway company which has a foundry unit for melting and casting different types of ferrous metals. This foundry unit consumes many types of graphite crucibles every year. There are many other foundry units attached to factories or operating independently. These units consume large quantities of crucibles. So far all the requirements of graphite crucibles are met through imports. Since all the raw materials for making the crucibles are found in the country, it is possible to produce graphite crucibles here at home both for domestic consumption and for export.

3 Source of Raw materials: The main raw materials used to make graphite crucibles are natural graphite, bond clay, ferro-alloys, borax and other minor chemicals, and silicon carbide. Most of the raw materials are found in different localities of the Amhara Region.

4 Process and Technology: Flaky graphite graded to suitable size is mixed with clay and grog in suitable proportion Silicon carbide and borax and water are also added at this stage and pan mill is used for mixing. The mixed mass is allowed to age for a few days. The mix is then pugged manually or passed through a dearing pug mill to ensure good mixing. Water is also added to make a dense mass which can be directly worked on jigger and jolly or crucible press. The formed crucibles are mostly sun dried and glaze coated and loaded into a round up draft kiln fired with coal. After firing, the crucibles are left to cool and thin removed from the kiln. Main machinery needed include disintegrator, pan mixer, ball mill (porcelain lined), pug mill, crucible press, hand press, screen, dies, moulds and testing equipment, direct fired round furnace.