CYCLOTRONS 2010 - List of Keywords (cryogenics)

Paper	Title	Other Keywords	Page
MOPCP008	Control System of Cryogenic Plant for Superconducting Cyclotron at VECC	controls, cyclotron, monitoring, superconducting-magnet	57
	U. Panda, T. Bhattacharjee, R. Dey, A. Mandal, S. Pal DAE/VECC, Calcutta, India
	Cryogenic Plant of Variable Energy Cyclotron Centre consists of two Helium refrigerators (250 W and 415 W @ 4.5K), valve box with sub-cooler and associated sub systems like pure gas storage, helium purifier and impure gas recovery etc. The system also consists of 3.1K liters of liquid Nitrogen (LN2) storage and delivery system. The plant is designed to cater the cryogenic requirements of the Superconducting Cyclotron. The control system is fully automated and does not require any human intervention once it is started. EPICS architecture has been adopted to design the SCADA module. The EPICS Input Output Controller (IOC) communicates with four Programmable Logic Controllers (PLCs) over Ethernet based control LAN to control/monitor 618 numbers of field inputs/ outputs. The plant is running very reliably round the clock, however, the historical data trending of important parameters during plant operation has been integrated to the system for plant maintenance and easy diagnosis. The 400 kVA UPS with 10 minutes back up time have been installed to keep the cryogenic system running with one 160 kW cycle compressor during utility power interruptions.

MOPCP076	Operational Experience of Superconducting Cyclotron Magnet at VECC, Kolkata	vacuum, controls, cyclotron, coupling	203
	U. Bhunia, M. Ahmed, R.K. Bhandari, T. Bhattacharyya, M.K. Dey, R. Dey, A. Dutta, A. Dutta Gupta, C. Mallik, C. Nandi, Z.A. Naser, G.P. Pal, U. Panda, S. Paul, J. Pradhan, S. Saha DAE/VECC, Calcutta, India
	The Kolkata Superconducting cyclotron magnet has been operational in the center since last few years and enabled us to extensively map magnetic fields over a year covering the operating range of the machine and successful commissioning of internal beam. The magnet cryostat coupled with the liquid helium refrigerator performs satisfactorily with moderate currents (<550A) in both the coils. The superconducting coil did not undergo any training and over the years has not suffered from any quench. Author would share the experience and difficulties of enhanced overall heat load to the liquid helium refrigerator at higher excitations of coils. This creates instability in the operation of liquid helium refrigerator and finally leads to slow dump. Rigorous study has been carried out in this regard to understand the problems and operational logic of liquid helium refrigerator has been modified accordingly to alleviate from. Some other measures have also been taken from cryostat and cryogenic distribution point of view in order to reduce the heat load at higher excitations.

WEM2CCO02	Operating Experience with the RF System for Superconducting Ring Cyclotron of RIBF	cyclotron, acceleration, vacuum, pick-up	338
	N. Sakamoto, M. Fujimaki, A. Goto, O. Kamigaito, M. Kase, R. Koyama, K. Suda, K. Yamada, S. Yokouchi RIKEN Nishina Center, Wako, Japan
	Since December 2006, Superconducting Ring Cyclotron (SRC) has been operational. Up to now, the beams of ²³⁸U, ⁴⁸Ca, pol-d, N, ⁴He have been provided for nuclear physics experiments. The SRC consists of 6 superconducting sector magnets, 4 accelerating cavities and one flattop cavity. Designed value of the acceleration voltage is 2 MV/turn. The gap voltage of 600 kV is excited with 130 kW rf power in the accelerating cavity. The cavities have been installed at four valley regions of 6 sector magnets and are exposed to a strong stray field of superconducting magnets. The strength of the magnetic field is as large as a few kilogauss. It is found that the condition of multipactor depends drastically on the strength of the stray field. How to treat the multipactor is one of the most important issues for stable operation of the SRC. This paper will discuss on our efforts to settle the problem concerning the cavities. By improving the vacuum, cooling, surface treatment and so on, we finally succeeded to minimize the break time due to the rf break down of the SRC cavities during experiments.
	Slides WEM2CCO02 [9.291 MB]

Paper

Title

Other Keywords

Page

MOPCP008

Control System of Cryogenic Plant for Superconducting Cyclotron at VECC

controls, cyclotron, monitoring, superconducting-magnet

57

U. Panda, T. Bhattacharjee, R. Dey, A. Mandal, S. Pal
DAE/VECC, Calcutta, India

Cryogenic Plant of Variable Energy Cyclotron Centre consists of two Helium refrigerators (250 W and 415 W @ 4.5K), valve box with sub-cooler and associated sub systems like pure gas storage, helium purifier and impure gas recovery etc. The system also consists of 3.1K liters of liquid Nitrogen (LN2) storage and delivery system. The plant is designed to cater the cryogenic requirements of the Superconducting Cyclotron. The control system is fully automated and does not require any human intervention once it is started. EPICS architecture has been adopted to design the SCADA module. The EPICS Input Output Controller (IOC) communicates with four Programmable Logic Controllers (PLCs) over Ethernet based control LAN to control/monitor 618 numbers of field inputs/ outputs. The plant is running very reliably round the clock, however, the historical data trending of important parameters during plant operation has been integrated to the system for plant maintenance and easy diagnosis. The 400 kVA UPS with 10 minutes back up time have been installed to keep the cryogenic system running with one 160 kW cycle compressor during utility power interruptions.

MOPCP076

Operational Experience of Superconducting Cyclotron Magnet at VECC, Kolkata

vacuum, controls, cyclotron, coupling

203

U. Bhunia, M. Ahmed, R.K. Bhandari, T. Bhattacharyya, M.K. Dey, R. Dey, A. Dutta, A. Dutta Gupta, C. Mallik, C. Nandi, Z.A. Naser, G.P. Pal, U. Panda, S. Paul, J. Pradhan, S. Saha
DAE/VECC, Calcutta, India

The Kolkata Superconducting cyclotron magnet has been operational in the center since last few years and enabled us to extensively map magnetic fields over a year covering the operating range of the machine and successful commissioning of internal beam. The magnet cryostat coupled with the liquid helium refrigerator performs satisfactorily with moderate currents (<550A) in both the coils. The superconducting coil did not undergo any training and over the years has not suffered from any quench. Author would share the experience and difficulties of enhanced overall heat load to the liquid helium refrigerator at higher excitations of coils. This creates instability in the operation of liquid helium refrigerator and finally leads to slow dump. Rigorous study has been carried out in this regard to understand the problems and operational logic of liquid helium refrigerator has been modified accordingly to alleviate from. Some other measures have also been taken from cryostat and cryogenic distribution point of view in order to reduce the heat load at higher excitations.

WEM2CCO02

Operating Experience with the RF System for Superconducting Ring Cyclotron of RIBF

cyclotron, acceleration, vacuum, pick-up

338

N. Sakamoto, M. Fujimaki, A. Goto, O. Kamigaito, M. Kase, R. Koyama, K. Suda, K. Yamada, S. Yokouchi
RIKEN Nishina Center, Wako, Japan

Since December 2006, Superconducting Ring Cyclotron (SRC) has been operational. Up to now, the beams of ²³⁸U, ⁴⁸Ca, pol-d, N, ⁴He have been provided for nuclear physics experiments. The SRC consists of 6 superconducting sector magnets, 4 accelerating cavities and one flattop cavity. Designed value of the acceleration voltage is 2 MV/turn. The gap voltage of 600 kV is excited with 130 kW rf power in the accelerating cavity. The cavities have been installed at four valley regions of 6 sector magnets and are exposed to a strong stray field of superconducting magnets. The strength of the magnetic field is as large as a few kilogauss. It is found that the condition of multipactor depends drastically on the strength of the stray field. How to treat the multipactor is one of the most important issues for stable operation of the SRC. This paper will discuss on our efforts to settle the problem concerning the cavities. By improving the vacuum, cooling, surface treatment and so on, we finally succeeded to minimize the break time due to the rf break down of the SRC cavities during experiments.

Slides WEM2CCO02 [9.291 MB]