TS-CV-Detector Cooling
TRACKER COOLING PLANT
Control system: measurements
and leak recovery procedures
M. Battistin, S. Berry, M. Bosteels, M. Pimenta, P. Tropea
11-Feb-04
P. Tropea - Tracker week - Control
1
TS-CV-Detector Cooling
CMS Tracker and Preshower cooling plant
General scheme
UXC55
Compressors
Secondary cooling
Chilled water
3 standard
cooling units
To Silicon Strip
and Pixel
cooling circuits
Condenser
Primary cooling
USC55
11-Feb-04
4 cooling units with
emergency fridge
P. Tropea - Tracker week - Control
To Thermal
Screen and
Preshower
cooling circuits
2
TS-CV-Detector Cooling
Installation of the cooling plant
UXC55
USC55
Secondary cooling plant
Primary cooling plant
11-Feb-04
P. Tropea - Tracker week - Control
3
TS-CV-Detector Cooling
Primary cooling plant functional scheme
Chilled water
Regulation
valve: for
chilled water
flow rate
regulation with
respect to the
p transmitter
on the tank
Compressors:
0÷100%
regulation
E-9
I-8
V-10
V-12
V-13
V-15
V-3
V-5
E-4
E-7
E-8
V-11
V-14
I-1
E-12
V-2
V-22
I-7
V-16
I-2
P
V-18
V-19
E-2
V-21
E-10
V-17
E-11
V-20
V-6
V-8
I-3
P
I-4
V-1
E-1
I-5
T
Storage tank:
• weight transmitter
• manometer and pressure
transmitter
• temperature transmitter
E-3
E-6
V-7
I-6
W
• electrical heater
• safety valve
11-Feb-04
V-9
E-5
V-4
Condenser: running
chilled water
(provided by CERN)
and R410A.
P. Tropea - Tracker week - Control
R410A to/from
UXC55
4
TS-CV-Detector Cooling
Primary cooling plant: USC55 zone CV
Compressor electrical
power distribution
rack
Main Unit hydraulic equipments:
• Compressors
• Tank
• Condenser
• Buffer
• Filters
11-Feb-04
P. Tropea - Tracker week - Control
5
TS-CV-Detector Cooling
USC55: electrical and control racks
Control racks: 470 valves for
electrical/pneumatic signal
conversion
2.5 m
0.9 m
3&4m
0.9 m
Electrical power distribution rack
& electrical part of the control racks
11-Feb-04
P. Tropea - Tracker week - Control
6
TS-CV-Detector Cooling
Secondary cooling plants: 7 detector units
2 x Silicon Strip
1 x Pixel
2 x Thermal Screen
2 x Preshower
PERFORMANCES DEMANDED
Cooling Units
Name
Silicon Strip 1
Silicon Strip 2
Pixel
Thermal Screen 1
Thermal Screen 2
Preshower 1
Preshower 1
SS1
SS2
PX
TS1
TS2
PS1
PS2
Total
11-Feb-04
Flow rate
Δ P
l/h
33638
33638
3564
3168
3168
6480
6480
bars
6
6
5
4
4
7
7
Power
T
°C
-30
-30
-20
-10
-10
-20
-20
kW min
38
38
9.2
5
5
13
13
121.2
P. Tropea - Tracker week - Control
kW max
52
52
10
7
7
13
13
154
7
TS-CV-Detector Cooling
Detector unit: hydraulic equipment
Heat exchanger:
evaporating the R410A
and cooling down the
C6F14
Expansion valve:
regulates the flow
rate of R410A with
respect to the T at
the distribution
V-9
V-28
V-11
I-1
V-13
To
CP1/
I-13
To
CP1/
I-12
V-6
E-5
To CP1
To CP2/I-8
CP1/I-10
T
I-4
To
CP1/
I-15
To
CP1/
I-14
V-29
To CP1
V-12
I-5
I-6
P
I-18
I-3
V-10
V-27
E-4
V-21
To CP2/I-9
CP1/I-11
V-3
V-16
V-17
E-7
V-4
V-2
E-2
Alumina
filters: to
avoid acids
Pump
11-Feb-04
V-20
V-24
V-15
E-6
I-17
V-19
V-26
Back pressure regulator:
to keep the pressure at
the distribution lines
constant
V-18
V-5
V-25
V-23
V-22
FI
I-2
V-14
To CP1/I-7
E-8
Low pressure reservoir: connected
to the vacuum pump on the
instrumentation rack, equipped with
manual valves, weight transmitter,
check valve
DW
V-7
E-3
I-16
V-8
P. Tropea - Tracker week - Control
8
TS-CV-Detector Cooling
Detector unit: distribution lines
To
CP1/
I-13
To
CP1/
I-12
V-6
E-5
To CP2/I-8
CP1/I-10
T
I-5
V-28
V-11
I-1
V-13
To CP1
To
CP1/
I-15
To
CP1/
I-14
V-29
I-4
To CP1
V-12
I-6
P
I-18
I-3
V-10
V-27
E-4
V-21
To CP2/I-9
CP1/I-11
V-25
V-23
V-22
I-17
V-19
V-26
FI
I-2
V-20
V-24
V-18
V-5
E-8
V-3
V-17
V-15
V-16
V-9
Pneumatic shut-off
valve with metering
Small pipesscrew
connecting the
inlet and outlet of the
calibrated orificeCalibrated
to the
orifice to
differential pressure
allow flow rate
transmitter located
on the
measurement
on the
instrumentation rack
basis of the
differential pressure.
E-7
E-6
V-4
V-2
E-2
V-14
To CP1/I-7
Pneumatic shut-off
valve
DW
V-7
E-3
11-Feb-04
I-16
V-8
P. Tropea - Tracker week - Control
9
TS-CV-Detector Cooling
Instrumentation on the racks next to the
cold boxes
Schrader valves for
Pressure indicators
I-8
I-9
Differential pressure
transmitters for flow
rate measurements
ThScr & Preshower:
all circuits
Pixel & SiStrip:
grouped lines
Vacuum pump to
lower the
reservoir inner
pressure
11-Feb-04
connection of optional
differential pressure
transducers, purging,
etc.
CP2
Pressure and weight
transmitters
P
P
W
I-11
I-10
I-7
DP
DP
I-12
I-13 I-14 I-15
DP
DP
Nitrogen network
distribution equipment
E-1
V-1
N2
P. Tropea - Tracker week - Control
10
TS-CV-Detector Cooling
Gastight boxes
• Inner dew point: -35°C
(compressed air flushing)
• Outer temperature: 14°C
•
•
•
•
•
•
11-Feb-04
Equipment
A bi-directional safety valve
A pressure indicator
A ball flowmeter
A light
A dew point transmitter
A retention bund connected
to the waste water network
P. Tropea - Tracker week - Control
11
TS-CV-Detector Cooling
Cooling rack installation in the UXC55
R410A from/to USC55
11-Feb-04
P. Tropea - Tracker week - Control
12
TS-CV-Detector Cooling
Measure signals from the cooling plant
• Temperature at the distribution line (pt100)
• Status of the distribution lines (grouped lines and
distribution lines, inlet and outlet, open or closed)
• Flow rate for the continuously monitored circuits
• Pressure and weight of the reservoir
Control on the distribution temperature
Control on the circuits to be open/closed
Leak & clog detection
11-Feb-04
P. Tropea - Tracker week - Control
13
TS-CV-Detector Cooling
Clog detection
• Flow rate measurement on the equipped
channels
• Temperature raise into the detector
Leak detection
Leaks can be detected by:
• Tank weight variation (~ scale reading: 1/1000
of the total tank weight)
• Pressure raise into the reservoir
• Vacuum pump activation frequency
augmentation
11-Feb-04
P. Tropea - Tracker week - Control
14
TS-CV-Detector Cooling
LEAK TYPES
Leak in the circuit part where p < p atm.:
• ptank raises,
• the vacuum pump activation frequency increases
Slow leak: no liquid dispersion in the circuit
Fast leak: some liquid can exit the circuit
Leak in the circuit part where p > p atm.:
• The tank weight decreases
• The vacuum pump frequency can decrease (no useful
parameter in this case)
Slow leak: only slight weight decrease
Fast leak: fast decreasing of tank weight
11-Feb-04
P. Tropea - Tracker week - Control
15
TS-CV-Detector Cooling
LEAK RECOVERY
Two possible approaches, to be chosen as a
function of the leaking rate, the needs of the
detector, etc.:
– All the valves stay open, and we close the
circuits one after the other to detect the
leaking one
– All the valves shall be closed, and we open
them one after the other to detect the
leaking one
11-Feb-04
P. Tropea - Tracker week - Control
16
TS-CV-Detector Cooling
PROCEDURE FOR LEAK RECOVERY:
ALL THE CIRCUITS OPEN
• Focus on the parameter that generated the “alarm” (tank
weight, inner pressure of the tank, vacuum pump activation
frequency)
• Close one distribution circuit at a time
• Leave time to the system to stabilize
• Measure variations of the given parameter:
No variations
(ex: p still increasing)
That’s not the leaking
circuit: re-open it and
pass to the following one
11-Feb-04
Significant variations
(ex: p stops increasing)
That’s the leaking
circuit: leave it closed!!!
P. Tropea - Tracker week - Control
17
TS-CV-Detector Cooling
Response times
• For leak detection: a few hours could be necessary for the
complete circuit analysis
• Set of the Temperature: in principle a few minutes (~10 min)
should be enough to stabilize the system: tests to be done
during commissioning
• Opening/closing of the circuits: immediate response (pneumatic
command)
• Timing between different commands: a “manual” with
recommendations will be given to the user after plant
commissioning, indication the minimum interval between each T
set up and between each circuit opening/closing (typical values
for similar plants ~ 10-20 minutes for OPENING, no problems
for immediate CLOSING)
11-Feb-04
P. Tropea - Tracker week - Control
18
TS-CV-Detector Cooling
CMS Tracker and Preshower cooling plant
technical specification demands
CONTROL SYSTEM
Demanded precision on the set temperature:
+/- 1 K
Demanded maximum overshoot for a step perturbation :
+/- 3 k
ADVANCED CONTROL SYSTEM
Integrating an advanced logic, allowing for higher performances in
terms of PRECISION and STABILITY: demanded as an option for
each detector cooling unit
11-Feb-04
P. Tropea - Tracker week - Control
19