·The heating element is made of Cr80Ni20. This metal have good mechanical capability at high temperature. It can be endured byalternating heating and cooling. The tiptop work temperature is above 1000℃ . It is the best heating element metal. Cracking tube whose shape is clubs can employ the hydrogen current distribute epuably. The heating mode which the heating element is beside the cracking tube can make cracking filly. The purity of gas is higher.
·The central material of heat preservation uses Japanese lsolite fiber board of light aluminum silicate for thermal insuliation. It is light but the intension is high.