·278·IMP&HIRFL Annual Report2019
7-31Conceptual Design of the Vacuum System in Target
Area of HFRS
Chai Zhen,Meng Jun,Luo Cheng,Yang Weishun,Xie Wenjun,Jiao Jiqiang,Niu Zhiwei and Ma Xiangli
A radioactive ion beam line,HIAF(High Intensity heavy ion Accelerator Facility)Fragment Separator(HFRS), is under design at the Institute of Modern Physics(IMP)at prent.According to the evaluation of the do in the target area of HFRS[1],electronic components and vacuum products would fail in a short time when HFRS works at the design current.Thus,a plug system design similar to the Super-FRS at GSI[2]has been propod to solve the problem.One of the technical challenges in HFRS beam line is the vacuum system design,which can work safely at the exposure of high levels of radiation.望帝春心托杜鹃>白螺
The model of vacuum system of target chamber is shown in Fig.1.The plug comprid a combination of devices more nsitive to radiation,massive mobile shielding,and beam interaction device asmbled.Due to the high levels of radiation,it is difficult to bolt theflange of the inrt and meet the re
quirements of installation accuracy.So called lf-weight al,which relies on gravity and atmospheric pressure as the tightening force,was developed and tested in October2009.A specially designed dovetail groove with a optimized depth was procesd on theflange face of the inrt,which could make the O ringfixed.Theflatness and roughness on both of the twoflange faces are 0.1mm and0.8µm respectively,which can ensure the accuracy when the plug installed into the vacuum chamber. Meanwhile,when the O ring with the hardness of75HS(elastic modulus of6.8×106Pa)was compresd to6.8mm which was the depth of dovetail,the leakage rate of the aling surfaceis less than1×10−9mbar.L/s,and the vacuum degree reach3.78×10−7mbar,as shown in Fig.2.
炒鸡的做法Fig.1(color online)Design of target chamber.Fig.2(color online)Test of lf-weight for target.
A prototype of the primary target chamber will be built in2020,and with it the vacuum al and positioning guide of the target will be jointly tested.
References
[1]Y.Yang,Nucl.Sci.Tech.,29(2018)149.
[2]Luis Miguel Orona.International Journal of Advanced Robotic Systems,10(11)(2013)1.doi/10.5772/57073.
7-32Design of Vacuum System of SSC-Linac西门豹
Xie Wenjun,Meng Jun and Li Changchun
In order to improve the performance of the Heavy Ion Rearch Facility at Lanzhou(HIRFL),the Separated Cyclotron Linac(SSC)-Linac was designed and constructed as the injector for the parated-ctorcyclotron(SSC).It mainly consists of a superconducting high-charge-state electron cyclotron resonance(ECR)ion source,a low energy beam transport(LEBT)line,a Radio Frequency Quadrupole(RFQ),a medium energy beam transport(MEBT)line, four drift tube linacs£DTL¤and a high energy beam transport(HEBT)line[1],as shown in Fig.1.The vacuum condition is<1×10−7mbar.
2019IMP&HIRFL Annual Report·279·
孟子是哪个朝代的人>钟无艳怎么玩Fig.1(color online)The general layout of the SSC-Linac.Fig.2(color online)The vacuum condition distribution
along the accelerator system.
The whole system adopts non-baking scheme.The rough-pump station of LEBT and HEBT consists of a Turbo Molecular Pump(TMP)with a pumping speed of550L/S and a dry pump with a pumping speed of4L/S.Roughing down to approximately10−6mbar and then switch on the Sputter Ion Pump(SIP)with a pumping speed of400L/s as the maintenance pump due to its high reliability,no moving parts,long life and high radiation resistance.The length of LEBT is only5m and the gas load is low,so only one tup with a rough-pump station and an ion pump is needed.The HEBT has two v
acuum chambers and two high-frequency cavities.Considering the significant pumping speed loss becau the small diameter of the vacuum pipes(Ø40mm),SIP is installed in each vacuum chamber and high-frequency cavity.Due to the large gas load of the RFQ and DTL,TMP pump with a pumping speed of1000 L/s and dry pump with a pumping speed of8L/s as the rough-pump station have been ud.Roughing down to approximately10−6mbar and then switch on the Cryopump with the pumping speed of1500L/s for N2as the maintenance pump.
怎样写辞职信The beam line is divided into4vacuum ctors by gate valves.The gate valves are interlocked by vacuum gauges. The valves also allow the repairing and modification of components without venting other ctors.Fast-closing valves were installed at the end of the HEBT to protect the adjacent part from a catastrophic vacuum failure(Fig.2).
朝花夕拾阅读
Due to the compact position of the entire beam line,some components have been optimized.The LEBT ction adopts a design scheme of embedding water-cooled conical oxygen-free copper inside the stainless steel vacuum pipe, as shown in Fig.3.In the MEBT ction,the welding of BPM,vacuum pipes and bellows is ud to reduce the installation space(Fig.4).
Relocation and commissioning was completed in2019and thefinal vacuum is better than5×10−8mbar.
Fig.3(color online)Water-cooled vacuum pipe.Fig.4(color online)Vacuum pipe+BPM.
Reference
[1]X.J.Yin,Y.J.Yuan,J.W.Xia,et al.,Physical Review Accelerators and Beams,19(2016)1.
