Semi GPC (SGPC) yana daga rufin rufi na acheson makera.The graphitization zafin jiki yana cikin kewayo. zafin jiki na 1700-2500C. Yana cikin samfurin jadawali zafin jiki. Yana da recarburizer na tattalin arziki tare da babban ƙayyadaddun carbon, ƙananan sulfur abun ciki, saurin rushewa da yawan sha.