On June 2, 2012, Mr.zhu have participate in the 22^nd international enamellers congress in Cologne, he visited Bosch Thermotechnik GmbH that it is focus on steel wall-mounted enamel water heater, condensate type enamel water heater, storage type enamel water heater, radiation enamel water heater, Solar energy enamel water heater. From the processes of material, sheet metal, welding, automated pre-processing production lines, automatic enamelling and firing the production line, assembly foam, automatic packaging production line. Mr. Zhu also has visited Wendel GmbH, this company mainly products are: enamel glazes, ceramic glaze materials base glazes and enamel ceramic pigments. After he finished the business trip and returned to China on June 18, 2012.