NA62 – GTK Cooling Station
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Main characteristics
• Fluid: C6F14 (fluorocarbon)• Operating temperature: -30 °C ÷ -10°C• Temperature precision: ±1 K• Temperature stability: ± 0,5 K• Flow rate (cooling loops): 7 ÷ 10 g/s• Operating pressure: 13 bar*• Tank pressure: - 0.7 bar• Number of circuits: 3
April 10th, 2015
• Maximum allowable pressure PS of the equipment in conformity with the European directive PED 97/23/EC
NA62 – GTK Cooling Station
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NA62 – GTK Cooling Station
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Coolant (C6F14) characteristics
• Fluid: C6F14 (fluorocarbon)• Non-toxic• Non flammable• zero ozone depletion potential
April 10th, 2015
• Tank capacity: 0.036 m3 • Total amount of C6F14 : 0.040 m3
NA62 – GTK Cooling Station
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Main characteristics
General Safety Issues
To prevent over pressure inside the circuits, when the cooling station is switched-off all valves (regulation valves, stop valves and pneumatic electro valves)/actuators are open (status normally open). So, the fluid can expand inside the tank during the warm-up (from – 25 degree up to ambient temperature). In case of over pressure due to mechanical failure of the valves, 21 pressure relief valves assure that, the pressure inside the circuits don’t exceed 13 bar. In case of leakage inside the detector, the fluid will be recovered into the return tank.This tank will be maintained in under pressure via a dedicated vacuum pump.
April 10th, 2015
NA62 – GTK Cooling Station
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Leakage inside the detector(s) In case of leakage inside the detector, the pressure (PT5101/02/03) at the inlet will decrease quickly. In this case, the cooling station control system will shut the loop(s) acting on the valve(s) GS5101/02/03 and GS5104/05/06. In case of over pressure (PT5101/02/03), the control system will stop the loop(s), acting on the valve(s) GS5101/02/03. In this case, the valve(s) GS5104/05/06 will be kept open to prevent aver pressure inside the detector.
In case of low flow rate (FT5101/02/03), the control system will stop the loop(s), acting on the valve(s) GS5101/02/03. In all these scenarios, the control system will send a signal (dry contact) to the DSS and DCS.
April 10th, 2015
NA62 – GTK Cooling Station
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Detector Safety System DSS 4 inlets and 4 outlets interlocks are available to be hardwired connected to the Detector Safety System (DSS).These allow the possibility to stop the cooling on each cooling loop separately or to stop the whole cooling system on DSS request.
April 10th, 2015
NA62 – GTK Cooling Station
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Detector Control System DCS It checks the following parameters: Temperature of the coolant at the inlet (T_in); Temperature of the coolant at the outlet (T_out); Coolant flow; Pressure at the inlet and at the outlet. Meaning that if the above parameters are within the allowed ranges, the status will be OK and the cooling station runs, otherwise the cooling station or the loop(s) will be switched-off. In this case, the control system will send a signal (dry contact) to the DSS.
April 10th, 2015
