r. guida, b. mandelli, m. corbetta cms gem gas system

CMS GEM GAS SYSTEM COMMISSIONINGR. Guida, B. Mandelli, M. Corbetta

CMS GEM GAS SYSTEM

CMS GAS SYSTEM COMMISSIONING 2

Mixer Module:

● 2-component mixer: Ar, CO2● Predisposition for a third line● Ar/CO2 70/30 will be used● CO2 100% for first months

CMS GEM GAS SYSTEM


Distribution Module:

● 2 pre-distribution groupsnegative/positive

● 3 distributions per groupGE1/1, GE2/1, ME0

● GE1/1 negative installed now● GE1/1 positive and GE2/1

will be installed in LS2 + Run3

CMS GEM GAS SYSTEM


Distribution Module:

● The system is designed to run with all 6 distribution racks,but it can be operated with only part of the racks

● After LS2, only Rack 61 and Rack 64 will be in use i.e. GE1/1 negative and positive endcap

● Rack 62 and Rack 65 (GE2/1) are already in place and complete, with bypass installed on flow cell manifold

● Rack 63 and Rack 66 (ME0) do not exist yet

CMS GEM GAS SYSTEM


CMS GEM GAS SYSTEM


Pump Module:

● 2 pumps installed● Pump operation is controlled

with a multiple loop● Valve PV4003 is regulated

based on the input pumppressure (set -4 mbar)

● Manual valves contribute tothe regulation (one in the loopand one at exhaust)

SYSTEM COMMISSIONING


The system was tested in different conditions to assure safe operation

● ON/OFF of Gas System ● Operation of distribution with four, three or two racks ● Operation of purge system > for single chamber flushing● Operation of backup system ● Setting and test of alarms

SYSTEM ON/OFF


The system was switched ON/OFF repeatedly to tune parameters

● Regulation parameters of Group Pumps were modified, to open the relative regulation valve fast enough

● Parameter to keep checked is the pressure at the output of each Rack● During switch ON, after small positive jump (up to 10 mbar), all racks reach

working output pressure which remains stable ● During switch OFF, after small increase in pressure,

Racks 61/62/65 are back to working pressure, Rack 64 still a bit higher>> see backup System

SYSTEM ON/OFF


Pout R62

Pout R61

Pout R64

Pout R65

ON OFF

GAS DISTRIBUTION


The system was tested in different conditions to assure safe operation

● System designed for 6 racks, now 4 are installed, only 1 or 2 will be operational during LS2 > work in different condition

● Manual valves at Pump level allow regulation of Pump operation,so that it is suitable for all configurations

● Valves needs to be regulated when passing from 2 racks operationto 3 or 4 racks operation

● The system does not manage a unique configuration of manual valvesfor all racks configuration

GAS DISTRIBUTION


PumpRegulation

2rack ON

4rack ON

manual valveregulation

sys stable

sys stable

3rack ON

sys stable

2rack ONMAX REACHED

3rack ON

4rack ONsys stable

PURGE SYSTEM


The purge system was tested on Negative distribution side (Group 1)

● The purge mixture is 100 CO2%● One chamber connected with input and output channels from manifold● Two i/o lines are available on the purge,

ideally one per each manifold of the Groupe (i.e. 2 racks)● Purge was open to about 10 l/h flushing the connected line (29)● Flow can be regulated with rotameter

BACKUP SYSTEM


The backup system allows to keep stable the pressure in the distributionwhen the system goes OFF

● Backup mixture is 100% CO2● Backup flow to each distribution rack can be regulated with rotameter

and a Zimmerli to set the correct pressure for each ● A first tune was done, Rack 61/62/65 are now at the correct pressure● Rack 64 needs correction of the Zimmerli

BACKUP SYSTEM


Rack 61, 4.6 mbarRack 64, 4.7 mbar

Rack 64, 8.3 mbar

Rack 61, 3.6 mbar

SystemOFF

SAFETY ALARMS


The integrated alarm system allows to put safety check on desired values:

● Mixer status, gas flow in MFC● Input/Output pressure of distribution racks● Value of regulation valves for the Pump module and

for the single distribution groups ● Ready status of distribution tacks ● Gas loss in various positions of the system ● ...

SAFETY ALARMS


CURRENT STATUS


The CMS GEM Gas System is now in Ready status

Next steps:

● OFF during week 45 for connection of GE1/1 negative chambers ● System ON when everything is ready and connected● Settings of the proper alarm on system pressure

r. guida, b. mandelli, m. corbetta cms gem gas system

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