This invention characterizes that cavity for vacuum-pumping contacts with activated suction materials in sealing then the remained gas in the cavity contacts with Zr like activated suction materials to increase the vacuity to above 10 to the power -3 pa. The combined set includes cavuity measurement device, main pumping induction chamber, secondary pumping induction chamber, releasing unit and vacuum pump each independent unit connects with interfaces of cavity for vacuum pumping by valves with the advantages of having Na, k, p, Ba and their alloys suction materials as the main pumping material and Z like suction material as the secondary pumping materials. |