The Design And Development Of Helium Pneumatic Tunner

Tuner is an important part of the accelerator’s high frequency system. It’s main function is to make high frequency cavity operate at designed frequency and work normally.The extruding tuner is based on the tuning range and mechanical property requirements of 162.5MHz HWR superconducting cavity supported by project“Strategy Guided Scientific and Technological Project of Chinese Academy of Sciences”. It’s fundamental principle is to change the helium pressure. The helium pressure would transform the shape of cavity, further cause the change of radio frequency cavity.In the text, the tuner’s design is based on Argonne laboratory’s design. On account of 162.5MHz HWR superconducting cavity’s mechanical structure, the tuner’s structure is designed and mechanics analysis was carried out. Test at the room temperature shows that the performance of the manufactured tuner meets the requirement of tuning range 300 KHz. Resolution test of cavity was based on gas mass flow control scheme. The test results show that the resolution precision of the tuner reaches 15 Hz which meets the tuning requirement. At last,the text analyzed the feasibility of the tuner by fluent. It is proved that the helium pneumatic tuner can be used at 4.2K temperature.