CMS LEWA LDE1/M500 CO 2 pumps N° N°

Order LEWA offer N°SLL from the 04/12/2013 DAI N° Created on the 13/12/2013 by Andrea d’Auria Order N°CA (1) sent to LEWA on the 16/12/2013 Pumps received at CERN on the 02/05/2014 and 13/05/2014

LEWA Pump N° Hydraulic oil leak history 20/04/2015 – 30/03/2016

Suspected gaskets Oil droplets Bolts that we have tried to tighten more but didn’t move… April 2015 First hydraulic oil leak detected in April 2015, after few hours of operations Mail sent to LEWA on the 20/04/2015

June 2015 First intervention of a LEWA technician on the 18/06/2015: Disassembly of the pump head and replacement of the damaged piston seal Problems during intervention: ◦Gear box oil in hydraulic circuit ◦Seal installed in wrong position JÉRÔME DAGUIN - EP/DT/FS

August 2015 Second intervention of a LEWA technician on the 05/08/2015: Disassembly of the pump head and replacement of the damaged piston seal Same intervention as on the 18/06/2015 Problems during intervention: ◦Hydraulic oil spilled on the floor Leak still present after few hours of operations… Mail sent to LEWA on the 07/09/ JÉRÔME DAGUIN - EP/DT/FS 6

September 2015 Third intervention of a LEWA technician on the 16/09/2015: Disassembly of the pump head and replacement of the damaged piston seal Scratch spotted on the piston. Polished with sand-paper Leak still present after few hours of operations… Mail sent to LEWA on the 25/09/ JÉRÔME DAGUIN - EP/DT/FS 7 Scratch on the piston Damaged seal Polished piston

December 2015 Forth intervention of a LEWA technician on the 04/12/2015: Disassembly of the pump head and replacement of the damaged piston and piston seal JÉRÔME DAGUIN - EP/DT/FS 8 Oil in the small reservoir

March 2016 After the intervention of the 04/12/2015, the pump was running with no leaks until the 14/12/2015 when it was stopped because of winter shutdown maintenance. Pump restarted on the 14/03/2016 and ran continuously until the 29/03/2016 On the 28/03/2016 around 17h00 the flow delivered by the pump (blue line) and the discharge pressure (yellow line) started to decrease with no apparent reason. Nothing was changed on the system at this time A visit on site on the 29/03/2016 revealed a new oil leak coming from the junction in between the head and the pipe connecting to the remote head The pump was stopped on the 29/03/2016 around 11:00. After consultation with LEWA technician all bolts were re- tightened and operation restarted… JÉRÔME DAGUIN - EP/DT/FS 9 Oil leak location Suction temperature Suction Pressure Mass flow Pump speed Discharge pressure

LEWA Pump N° Membrane spikes history 02/06/2015 – 30/03/2016

June 2015 First pressure spike in between the membrane spotted on the 02/06/2015 After discussion on the phone with LEWA, we inspected the head to check the presence of oil in between the two membranes (report from the 03/06/2015). No oil was found. On that date the head was found not properly tightened (4 out of 6 bolts not at the nominal 85 Nm torque) JÉRÔME DAGUIN - EP/DT/FS 11

November 2015 Pressure spikes reappeared in November and became problematic (pressure stayed high in between the two membranes) after 30/11/2015 Mail sent to LEWA on the 01/12/ JÉRÔME DAGUIN - EP/DT/FS 12 18/11/ /11/ /11/2015

December 2015 Operation not possible after the 01/12/2015: pressure in between the membranes rises after few minutes of operations… Mail sent to LEWA on the 02/12/ JÉRÔME DAGUIN - EP/DT/FS 13

December 2015 On the 04/12/2015, a technician from LEWA came to work on the other pump Describing our problem on this pump, he decided to replace the membrane (using our spare kit) During the intervention the ring that holds the membrane was found damaged Since no spare part was available on that day it was decided to reassemble the membrane with that ring and to change it in a later stage when available from the factory No pressure spikes were observed since the membrane replacement The pump was running from 04/12/2015 until 14/12/2015 and is now back in operations since 14/03/2016 On the 29/03/2016 we inspected the pump head (at the same time we inspected the other pump) and found some oil drops at the bottom of the head and few cm 3 in the bucket placed under the head This pump however does not show any signs of performances degradation and is still running up to now JÉRÔME DAGUIN - EP/DT/FS 14 Damaged membrane ring