Vacuum pumps

Tender description

Design and manufacture of cryogenic transfer lines. The UK Atomic Energy Authority is a non-departmental government body carrying out research into the potential of nuclear fusion as a future source of energy. One such fusion experiment is the Mega Amp Spherical Tokamak (MAST), which has recently undergone an extensive upgrade programme referred to as MAST Upgrade (MAST-U). The MAST Upgrade Enhancements (MAST-U ENH) project will deliver additional enhancements that will further develop the capability of MAST-U. One of the new components central to achieving these enhancements is the Double Beam Box (DBB), a double neutral beam injection system that will deliver 5MW of neutral power from 2 beams. Cryopumping has been selected as the method of in-vessel pumping for the DBB to achieve the required pumping speed of 1 500 m3/s. This will be realised with a serial open structure consisting of pumping cryopanels (cooled by liquid helium at temperatures provisionally between 4.2oK and 4.5oK) and shielding cryopanels cooled by liquid nitrogen at 80oK. Cryogens will be supplied by a cryoplant and associated valve box that are currently being designed and procured. As the DBB will be installed around pre-existing infrastructure, a number of challenges and limitations exist that will need to be considered early on in the concept design phase of the cryogenic transfer lines. For example, there are structures around the DBB that may place significant constraints on transfer line design if the preferred routing through the bottom of the vessel is to be achieved. Further details of the project and work scope can be found in the accompanying technical information document, which also describes the current maturity of the cryopump concept design. A separate sheet of market sounding questions is also included to promote discussion. Responses from external organisations will be used to help further refine our procurement strategy for this sub-system. The main purpose of this notice is to investigate the feasibility of vessel feed through and associated cryogen transfer line concepts and identify the capability and capacity of industry to realise this scope. The responses to this notice and any subsequent conversations with suppliers will inform a future invitation to tender.