Assembly & Operation
In addition to the various and complementary skills developed by ALCEN for the design and manufacture of fusion reactor key components and sub-assemblies, and its proven track record of significant achievements in major programs, the Group has also developed recognized expertise in work and services related to the assembly, operation and maintenance of complex facilities.
Developing on its expansive technological background and its long experience in the operation of industrial facilities and management of long-term programs, ALCEN is able to deploy dedicated staff to customer sites as well as the resources to conduct assembly work and to operate and maintain specialized facilities, especially under harsh environments.
All operations are performed in compliance with specific Environment, Health and Safety constraints imposed by the customer.
ALCEN 's subsidiaries for Assembly & Operation
Combining the expertise and resources of the Group's four subsidiaries, ALSYMEX offers its customers high added-value solutions and services:
- Feasibility studies
- Engineering: machining, welding, vacuum
- Detailed design: mechanical, thermomechanical, seismicity, vacuum, optical
- Creation of high-precision mechanical and opto-mechanical assemblies: sheet metal work, mechanized welding, machining
- Integration of complex systems in ISO 5 to ISO 8 class clean environments
- Non-destructive testing
- On-site installation
- Maintenance of mechanical, opto-mechanical, vacuum and high-voltage systems for large scientific instruments and nuclear-powered sites
- Major program management
ALSYMEX is active in the fields of defence, energy, aeronautics and major research infrastructures.
On-site integration of LMJ laser amplification sections
Within the framework of the French MegaJoule Laser (LMJ) program, ALSYMEX was selected to design, manufacture and assemble the laser amplification section (with the exception of the amplifier itself) in 2003. This type of section, known as SAHA, comprises, for each of the 22 laser lines, a 105 metre-long, 100-tonne mechanical structure assembly containing opto-mechanical equipment controlling the propagation, shaping and optimization of laser beams.
After factory acceptance, all constituent parts and sub-assemblies were shipped to the LMJ site for final assembly. On-site works can basically be divided into two main phases associated with separate locations.
Cleaning and equipping of mechanical infrastructure
A dedicated workshop, PUPS (“Plateforme d’UltraPropreté SAHA”) belonging to CEA, has been fully defined and equipped with all required facilities by ALSYMEX according to specific constraints related to SAHA equipment manufacture and French ICPE regulations (air treatment, sewage management…). With a surface area of more than 13,000 m2, it is operated by ALSYMEX and includes seven areas:
- Office zone
- Entrance deck
- Large dimension washing machines
- ISO8 and ISO5 integration halls
- Storage area
- Shipment deck
- Utilities area (air cleaning and sewage treatment)
Once shipped to the PUPS, the mechanical structures are cleaned according to ISO5 (inner surfaces) and ISO8 (outer surfaces) requirements. Geometrical characterization, using laser trackers, and, whenever required, vacuum tests are then performed in the integration hall.
At the same time, opto-mechanical systems, fully assembled in the Tarbes ISO5 clean room, are shipped to the same location for final integration, within ISO5 moveable zips, inside the mechanical structures. Final characterization of the fully equipped systems is done prior to transport on specially designed ISO8 vehicles to the dedicated LMJ laser hall.
Final assembly and integration of the complete SAHA
Operations mostly included handling of the equipped structures and assembly of the complete 100 m amplifying sections in the ISO8 laser halls. Final acceptance was done in conjunction with the customer by simulating the propagation of a laser beam through the entire line.
All of this work was performed by subcontractors under the supervision and responsibility of ALSYMEX and according to the customer’s safety and operating regulations: The LMJ has recently been integrated within the CEA CESTA site, classified as an INBS (Installation Nucléaire de Base Secrète, or Secret Basic Nuclear Facility) according to French Regulations.
At the current time, 17 lines have been fully integrated (3 laser halls completed).
All together, the work performed at the PUPS and the LMJ laser halls involved a team of 35 staff members (20 ALSYOM permanent employees and 15 sub-contractor employees).
Assembly of the XFEL Cryomodules
XFEL is a research facility under construction in Hamburg. It will generate extremely intense X-ray flashes (109 times stronger than the best conventional sources). To achieve this, bunches of electrons are accelerated to high energies and then directed through special magnet arrangements. The total length of the facility is 3.4 km, including a 2.1 km accelerator consisting of 800 superconducting RF cavities, grouped into 100 cryomodules.
CEA is responsible for cryomodule assembly. Major components (cavities, couplers, vacuum vessels, thermal shields), supplied by various partners, are assembled into cryomodules at a dedicated facility built for this type of work in Saclay (France). ALSYMEX has been awarded the contract to operate this facility and to manufacture the modules following procedures defined by CEA and DESY (Hamburg).
Initial operations in an ISO4 clean room include the assembly of RF coupler sections and cavities and assembly of strings of 8 cavities.
Strings are then laser tracker-aligned and fixed on the cold mass outside of the clean room. Thermal screens are welded prior to insertion of the complete system inside the cryostat.
Coupler warm sections, pumping lines and current feed-throughs are mounted and/or welded. Lastly, vacuum, RF and electrical tests are performed before closing under nitrogen and shipment to Hamburg.
Main characteristics of the cryomodules
- Dimensions: 12 m long × 1 m in diameter
- Weight: 7 tonnes
- Ultimate operating pressure: 10-4 Pa
- RF cavities cooled by liquid helium (2 K) – Operating pressure of 0.12 MPa
- Thermal shields at 8 K and 80 K
Operation of the Sol Gel Coating facility for LMJ optical components
Achieving the requested transmission performance levels for all the optical components of the LMJ required a special coating technique to be used. This technique, called Sol Gel, has been specifically developed by experts at the CEA. All LMJ optical components must be treated using this technique prior to installation on the machine, as well as regularly during operation, as the coating has a limited lifetime.
Having industrialized and manufactured some of the coating tools, ALSYMEX was awarded a multi-year framework contract to operate and maintain the Sol Gel facility located in the vicinity of the LMJ building in 2011.
In addition to coating operations, work performed at the Sol Gel facility included:
- Upgrading laboratory technology into an industrial process
- Facility management, including compliance with French safety requirements
The Sol Gel facility is classified as an ICPE according to French regulations. This involves commitment and the obligation to fulfil requirements relating to the environment and, in particular, to ensure traceability of the various chemical products and to oversee and/or monitor the disposal of chemical waste materials.
Since certain areas of the building are also classified as ATEX facilities (explosive atmospheres), ALSYMEX had to implement collective and/or individual protection systems and procedures to guarantee the safety of the process for people working at the facility.
The transfer of technology from CEA to ALSYMEX took one year and led to the qualification of 5 different processes using two types of coatings. Since mid 2012, business has been growing by 50 % per year, in line with the customer expectations. At the current time, 7 members of staff are continuously working on this project, a capacity which can easily be increased to 15 staff members to handle full capacity.
ALSYMEX oversees the maintenance of all machinery directly involved in the coating process and manages subcontractors for building and clean-room maintenance.
Maintenance of the LMJ demonstrator
Prior to the LMJ, CEA decided to design and build a demonstrator facility (LIL) in order to:
- Validate the expected performance levels of the LMJ
- Define the operational organization
- Train staff
The “LIL” was in operation from 2002 to the beginning of 2014 and comprised:
- A laser chain, a full-scale prototype of one of the 22 LMJ laser lines. This chain enabled optimization of the overall laser chain design and manufacture prior to its implementation on the LMJ.
- An experimental vacuum chamber (4.5 m diameter – 17 tonnes) equipped with a target and various measurement and diagnostics devices.
In 2003, ALSYMEX was awarded a 10-year contract for the deployment of operational maintenance of the entire facility under CEA management as per CEA quality, safety and environmental regulations, and, secondly, for actual completion of maintenance on the optical, vacuum and high-voltage systems of the laser line.
The activities, conducted in a facility dedicated to that purpose in the vicinity of the LIL building, varied over time and depended on actual customer requirements. It involved a core team of 10 staff members (ALSYMEX employees) which was increased to 25 staff members during shutdown periods (twice a year).
The first stage of the project was mainly dedicated to “maintenance engineering”:
- Re-engineering of the different components and systems
- Elaboration of the maintenance schedule and documents as per CEA’s management organization and quality, safety and environmental regulations
- Drafting of technical instructions
- Planning and operational coordination
These activities were followed by actual maintenance operations and concluded, in 2014, with the dismantling of the LIL main assembly:
- Maintenance of opto-mechanical systems, in ISO8 to ISO4 clean rooms belonging to CEA
- Maintenance of vacuum systems (from 10-2 to 10-6 MPa) in laser mechanical structures and the experimental chamber
- Maintenance of high voltage connectors between the power supply and laser lines (energy bench)
- Definition and use of the proper tools and control/command systems to cover maintenance operations
- Use and technical management of a steam generator for the clean-room washing machine.