OPERATIONS GROUP
CYCLOTRON TANK COOLDOWN PROCEDURES
Revision 19 - 22 June 2012 - Peter Yandon - (original: 24 April 1991)
This document is intended to be used as both instructions and as a checklist for bakeout. The author assumes that anyone using these instructions has a basic knowledge of the location and operation of the devices mentioned herein.
INDEX
1. LOWERING CYCLOTRON TEMPERATURE FOR OPERATION
1.01 RECORD TEMPERATURE OF AL-ALCW SYSTEM
1.02 START COOLDOWN
1.03 MONITOR TEMPERATURES
1.04 MONITOR THREE-WAY VALVE POSITION
1.05 MAINTAIN COOLDOWN RATE
1.06 END COOLDOWN
1.07 START R.F. TRANSMISSION LINE COOLING
1.08 START MAIN MAGNET COIL and BUSS BAR COOLING
1.09 START R.F. BOOSTER COOLING
1.10 START R.F. DEFLECTOR COOLING
1.11 START DEIONIZERS
1.12 SET INTERLOCKS
1.13 CHECK RESONATOR TEMPERATURE SETPOINT
1.14 MONITOR TEMPERATURE
1.15 SET R.F. THERMOCOUPLE WARNING AND TRIP TEMPERATURES
1.16 OPEN NORTH HEAT EXCHANGER
1.17 SET THREE WAY VALVE CONTROL TO NORMAL 2. R.F. BOOSTER COOLING SYSTEM
2.0 OVERVIEW
2.1 START UP
2.2 BAKEOUT
2.3 SHUTDOWN / SYSTEM ISOLATION
1.0 - LOWERING CYCLOTRON TEMPERATURE FOR OPERATION 1.01 - 1.17
Before proceeding, initial checks should be made to see if there are any special instructions (Blue Book notes etc.) in effect before starting the cooldown.
* * * DO NOT TURN HEATERS OFF ! * * * (see 1.06)
1.01 - RECORD TEMPERATURE OF AL-ALCW SYSTEM
The thermocouples displayed on XTPAGE "2Y" may take up to six hours to cool down below the normal warning and trip levels (which are the same as those set on XTPAGE "2T"). Therefore implementation of this instruction may have to be delayed.
2.0 - R.F. BOOSTER COOLING SYSTEM 2.1 - 2.3
OVERVIEW
The R.F. booster is cooled by the CU-ALCW system. It is important at all times to prevent condensation from forming on the booster elements. This can happen anytime the tank is not at vacuum, and can happen at a molecular level during bakeout due to temperature difference. Therefore the cooling must be shut off for bakeout. In addition the booster cooling must be on during main R.F. operation as the induced voltages may reach 10kV if the system is detuned from resonance. Therefore the cooling must be on for any R.F. operation.
There are three cooling circuits involved with the R.F. Booster : Upper booster, Lower booster and
Coupling Loop. The valves for these circuits are located in the vault basement, on the inside of the north
cyclotron shielding support wall, in the vicinity of the booster itself. Both the Upper and Lower cooling loops have
flow switches in their return lines. The valves descriptions follow :
A - The Upper and Lower booster supply valves are red handled ball valves located downstream of the red-and-white handled valves off the supply header. *** DO NOT adjust the red-and-white handled valves ***
B - The Upper and Lower booster return valves are blue lever handled gate valves located on the return header.
C - The booster Coupling loop uses red lever handled ball valves for both the supply and return lines. These valves are located about six feet upstream of the previously mentioned valves, on the supply and return headers.
D - The three cooling loops each have an unlabelled drain valve on both the supply and return lines, on the booster side of the supply and return valves. (Note: Upper/Lower Booster Supply drains are on wrong side of shut-off. Drains should not be a concern for bakeout, anyway.)
All supply and return valves MUST BE OPEN for ANY beam or booster operation.
2.1 - START UP
2.12 - Set the three return valves to full open position (see B and C above)and check for leaks.
2.13 - Set the booster Coupling loop supply valve fully open (see C above)and check for leaks.
2.14 - Set the Upper and Lower booster supply valves fully open (see A above). Check for leaks.
2.2 - BAKEOUT
During bakeout the entire booster cooling water flow must be stopped (see 2,0 Overview).
2.10 - Ensure that the water lines are intact.
2.11 - Check and close the six drain valves. (see D above)