CYCLOTRONS 2010 - List of Keywords (superconducting-magnet)

Paper	Title	Other Keywords	Page
MOPCP008	Control System of Cryogenic Plant for Superconducting Cyclotron at VECC	controls, cyclotron, cryogenics, monitoring	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.

MOPCP095	Experiment and Analysis: Partial Loss of Insulation Vacuum in K-500 Superconducting Cyclotron During Energization	vacuum, cyclotron, controls, extraction	248
	P. Bhattacharyya, M. Ahammed, S. Bandyopadhyay, R.K. Bhandari, U. Bhunia, J. Chaudhuri, A. De, A. Dutta Gupta, C. Mallik, A. Mukherjee, C. Nandi, U. Panda, S. Saha, S. Saha DAE/VECC, Calcutta, India
	At higher currents in superconducting coil of K-500 Superconducting cyclotron, it was found that the insulation vacuum surrounding the LHe vessel gets worsen with increased current in the coil,finally leading to slow dump of power of the coil. This is a limitation for further increasing current value in the superconducting magnet coil. But once the current value returned to zero, vacuum reading reaches its initial value. Experiment & analysis have been done to quantify the contribution of molecular gas conduction on heat load because of this partial loss of insulation vacuum. Experiment was done to quantify how much betterment in terms of heat load is possible by incorporating additional vacuum pump. The cryostat safety analysis because of loss of insulation vacuum has become very important at this new scenario. Analysis has been done to know what could be the maximum pressure rise with time in case of loss of vacuum. This data has been used to know what should be the relieving mass flow rate to avoid any pressure burst accident. Finally this data has been compared with the existing relief valve. It is found that the existing safety system can take care of such incident.

Paper

Title

Other Keywords

Page

MOPCP008

Control System of Cryogenic Plant for Superconducting Cyclotron at VECC

controls, cyclotron, cryogenics, monitoring

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.

MOPCP095

Experiment and Analysis: Partial Loss of Insulation Vacuum in K-500 Superconducting Cyclotron During Energization

vacuum, cyclotron, controls, extraction

248

P. Bhattacharyya, M. Ahammed, S. Bandyopadhyay, R.K. Bhandari, U. Bhunia, J. Chaudhuri, A. De, A. Dutta Gupta, C. Mallik, A. Mukherjee, C. Nandi, U. Panda, S. Saha, S. Saha
DAE/VECC, Calcutta, India

At higher currents in superconducting coil of K-500 Superconducting cyclotron, it was found that the insulation vacuum surrounding the LHe vessel gets worsen with increased current in the coil,finally leading to slow dump of power of the coil. This is a limitation for further increasing current value in the superconducting magnet coil. But once the current value returned to zero, vacuum reading reaches its initial value. Experiment & analysis have been done to quantify the contribution of molecular gas conduction on heat load because of this partial loss of insulation vacuum. Experiment was done to quantify how much betterment in terms of heat load is possible by incorporating additional vacuum pump. The cryostat safety analysis because of loss of insulation vacuum has become very important at this new scenario. Analysis has been done to know what could be the maximum pressure rise with time in case of loss of vacuum. This data has been used to know what should be the relieving mass flow rate to avoid any pressure burst accident. Finally this data has been compared with the existing relief valve. It is found that the existing safety system can take care of such incident.