XFEL Cold mass & vacuum vessel non-conformities Detected At saclay 2015 XFEL Cold mass & vacuum vessel non-conformities Detected At saclay WG cryomodule TTC 2015 @ SLAC / Thierry Trublet – CEA Saclay

72 cryomodules have been delivered up until now Introduction In the context of the XFEL project, CEA is in charge of assembling the 100 linac cryomodules 72 cryomodules have been delivered up until now The XM100 will be delivered at the end of April 2016 CEA has contracted with ALSYOM for assembly DESY provides cold mass & vacuum vessels 44 out of 45 delivered by ZANON 32 out of 55 delivered by IHEP XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Deliveries Cold mass & vacuum Vessels are delivered separately (the cold mass is not delivered inside the vacuum vessel as planned at the beginning) The hardware and 8K/70K shields are delivered one week before cold mass for preparation XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Non-conformities detected at Saclay We have been faced with several types of non-conformity and they are recurrent mainly on hardware, shields and cold mass. The cold mass is a complex manufactured component and requires careful inspection during the fabrication process. Parts were frequently missing on the hardware (true for all parts of the cryomodule) Most of the non-conformities led to additional work at Saclay (repair, rework, replacement). Only 1 cold mass and 1 vacuum vessel were returned for repair to DESY XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main non-Conformities Main non-conformities on cold mass / Vacuum vessel 4K-70K shields / Hardware Picture Main non-Conformities Provider p6 GRP (Gas Return Pipe) bent IHEP Cold mass p7 Diameter of GRP oval or too large IHEP ZANON p8 4K superinsulation eaten by mice p9 Hole for locating pin not deep enough IHEP  p10 4K superinsulation was mounted on right side or left side of the ZANON cold mass ZANON p11 Weld bead prevents assembly of washer and screws for fastening the needle support - Cavity support frame p12 The surface for fitting the big flange was too rough ZANON  p13 Paint and dirt inside threaded holes on several ZANON and IHEP vacuum vessels.  ZANON Vacuum vessel p14 The shape of the 70K was non-conform on several ZANON 70K shields and a few IHEP shields  IHEP p15 8K Coupler Copper braids were too short (IHEP) 70K shield XFEL cold mass & vacuum vessel non-conformities detected at Saclay– TTC 2015 @ SLAC

Main Cold mass non-conformitIES GRP bent GRP (Gas Return Pipe) bent Invar rod & clamps Cavity string The GRP on IHEP cold mass was bent (on 4 CMs) Consequence: the pin on certain cavities is in contact with the invar rod clamp The clamps have been reworked XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Cold mass non-conformitIES Diameter of GRP oval or too large The GRP diameter on IHEP cold mass was oval (on 2 CMs) Consequence: the mandrels could not be installed in the GRP New modified mandrels have been sent by DESY Mandrels positioned in the GRP The diameter of GRP on ZANON cold mass was too large (on 2 CMs) Consequence: the mandrels cannot be fastened in the GRP Aluminium sheet has been placed between GRP and mandrels End cap clamped in the mandrels and on the vacuum vessel XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Cold mass non-conformitIES 4K superinsulation eaten by mice on IHEP cold mass (on 2 CMs) The superinsulation has been repaired XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Cold Mass non-conformitIES Locating pin loose in the posts on IHEP Vacuum vessel (wrong pin hole dimension) Risk: the alignment reference for cavity positioning could change after dismantling/mounting the posts CX015 will be sent back to DESY for repair CX023 will be used as is because 1 in 2 pins is clamped correctly and the locating defect is acceptable XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Cold mass non-conformitIES 4K superinsulation was mounted on right side or left side of the ZANON cold mass Consequence: 2 different assembly procedures were therefore required (cutting holes for couplers is easier if the superinsulation is mounted and rolled to the coupler side) Hole for coupler coupler 4K superinsulation rolled on coupler side XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Cold mass non-conformitIES Weld bead prevents assembly of washer and screw for fastening the needle support - Cavity support frame (on ZANON and IHEP cold mass) Solution: the washer is removed or we grind the weld needle support Cavity string hanging via needle bearings Cavity support frame XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Vacuum Vessel non-conformitIES The surface for fitting the “big flange” was too rough. The marks of the milling tool were visible on at least 4 ZANON vacuum vessels Solution: The surfaces were re-machined by DESY at Saclay XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Main Vacuum Vessel non-conformitIES Paint and dirt inside threaded holes on several ZANON and IHEP vacuum vessels. Solution: the threaded holes are re-worked and cleaned by operators Clean room assembly process VS XFEL cryomodule performances – TTC 2015 @ SLAC

70K shields non-conformity The shape of the 70K was non-conform on several ZANON 70K shields and a few IHEP shields Consequence: The 70K interface of the coupler touched the shield when the coupler antenna was moved Solution: the shields were cut to enlarge the passage Before After XFEL cold mass & vacuum vessel non-conformities detected at Saclay – TTC 2015 @ SLAC

Non-conformity on the Hardware 8K Coupler Copper braids were too short (IHEP) Consequence: Copper braids were replaced XFEL cold mass & vacuum vessel non-conformities detected at Saclay– TTC 2015 @ SLAC

Production des cryomodules XFEL - Journées AFF-CSS @ Aussois 2015 Commissariat à l’énergie atomique et aux énergies alternatives Centre de Saclay | 91191 Gif-sur-Yvette Cedex T. +33 (0)1 69 08 xx xx | F. +33 (0)1 69 08 99 89 Etablissement public à caractère industriel et commercial | RCS Paris B 775 685 019 DSM Irfu DIR Production des cryomodules XFEL - Journées AFF-CSS @ Aussois 2015