IBBelle: Status & Plans 2-phase CO2 cooling system for PXD and SVD Minimal temperature: - 40oC (intended: -30oC) Cooling power: 3 kW (needed: ~1060 W) Developed by NIKHEF (MARCO prototype built at MPP) Version for ATLAS IBL (built by NIKHED/CERN, some components by MPP) In operation at CERN Copy* for Belle II under construction at MPP *except: control system changes from PVSS to EPICs

Commissioning Install and debug software (necessary changes, EPICS!): PLC EPICS: Check complete setup (with CERN expert) Basic functionality tests (SCADA instructions and expert commands). Pressurize complete system with N2 and check for tightness. Fill with liquid CO2, run without insulation (cannot reach design temperature) Complete foam insulation Operate at design temperature Safety inspection => June 29/30 Long term tests => July and later at KEK Response to change of operation conditions (load on/off…) Exercise maintenance and emergency scenarios.

Commissioning Test for dry out: Tset = -30°C, flow: 12 g/s Increase heater power: 2500W => 2950W 2900W 2950W 2750W 2800W Flux increased to 16 g/s 2500W Heater surface temperature Dry out Dry out can be controlled by increasing flux Gas temperature at outlet of heater is not very sensitive to dry out!

Commissioning Optimization of regulation parameters Setpoint of superheating after main heat exchanger Choose setpoint to achieve lowest CO2 temperature

Commissioning Power off: Regulation in the range of 1000W – 3000W works without problems But switching off from 1000W to 0W causes instabilities Regulation is too slow and the chiller switches off Solution: Dummy load of internal heater (tested, works) Tuning of regulation parameters (in progress)

New Features CO2 monitor (with flashlight and sound) was installed (can be read by EPICS) Gauge to weigh accumulator and measure the CO2 content

Interlocks IBBelle outputs 3 interlock signals DSS_AL1: IBBelle off/on DSS_AL2: IBBellle interlocked DSS_AL3: IBBelle running, but chosen temperature not yet reached Inverted logic: signal is true if alarm is off

Services Compressed air (6 bar, ok) flexible tube (standard) will be provided by MPP sample of connection pipe at KEK Water pipe connection (25°C, 3 bar) Flexible hose sufficient. Sample of connection type at KEK. Network Lan required, power for switch close to JB (Ito-san) CO2 connection IBBelle  transfer line  JB VCR, 3/8 and 1/2 inch. CO2 Connection JB <-> manifolds: Vacuum for Flex lines: 10-7 bar => ok 400V 3-phase transformer

Still to do Monitoring of environment (humidity, temperature) R404a filling: By company. Quantity: 12 kg. Needed in October CO2 filling: by us or KEK group, need 3 bottles 50kg (with rising pipe) in B1 Crane tool Fork to lift pumps with the crane (only if unit B installed) Documentation In work, will be at: https://confluence.desy.de/display/BI/IBBelle

To and in KEK Shipment in August (week 34) => 40 days => arrival early October Company: ITK / K-Line Logistics Will be humidity protected (packing by specialized company) Will come in a 40’ container (with JB etc) Unpacking at Tokyo port, with truck to KEK and into hall Formalities in preparation with KEK (Tsuboyama-san) Commissioning starting in October (by MPP team) Make connection tube as soon as IBBelle, JB and manifold is in place Service connection (electricity, water, air) Pressure tests Fill wit R404A (company) and CO2 Commission with internal heater (and/or JB ?) Connect to transfer lines and JB Interlocks EPICS implementation Prepare for cold tests of flexlines (December?) Training of KEK operation team