No abstract available

[en] The articulated boom system is the favourite in-vessel handling system for NET which will be used to maintain or replace in-vessel components during short term interventions. The testbed EDITH is the prototype of this system and is the logical step between the proof of principle of the system, which is already performed by the JET articulated boom, and the operational equipment for NET. EDITH is required to demonstrate that maintenance of plasma facing components can be carried out with the anticipated reliability and time. To achieve this aim EDITH is based on the experience of the JET boom and will be constructed in full scale, supplemented by a full scale mock-up. A further goal of EDITH is to allow the testing of boom components and subassemblies. The results of preliminary investigations for the boom are summarized, the need of the testbed EDITH and a full scale mock-up is discussed and both EDITH and the mock-up are described. (orig.)

[en] Economical operation of a fusion reactor requires intensive maintenance. For this purpose and due to the special conditions with regard to the components of a fusion reactor, remote handling instruments and machinery have to be developed. The state-of-the-art of such remote handling technique, in particular of multi-purpose and special devices (master-slave-manipulators), is described. (DG)

[en] The articulated boom system (ABS) is an optional part of the basic equipment to maintain invessel components of the NET/ITER fusion device during shutdown phases. Due to the high γ-radiation and after-heat of the activated components in-vessel handling equipment is subject of degradation which limits the lifetime of the equipment and thus also its availability due the necessary equipment maintenance. It is the aim of irradiation tests to provide the basis for the qualification of radiation and temperature sensitive equipment components by modification of standard components in collaboration with the suppliers in order to enhance their life expectancy. Besides sensors, resolvers, electronic and optical components which are not subject of this document, motors and related components are the most sensitive elements and were tested in an extensive program. The results of the experiments leading to a motor radiation hard up to 80 MGy-Si at winding temperatures of 250 C are described in this document. (orig.)

[en] For the exploration of marine mineral deposits in shelf areas additional systems will be required in order to supplement the results of other methods and determine in a short time the amount and the concentration of the minerals. The neutron induced γ-radiation measurement is an appropriate method for this problem. To obtain high-resolution analysis it is necessary to use Ge(Li)- detectors. The employment of cryostats keeping the diodes at low temperature is only applicable to scientific but not to industrial applications. In this case, cryogenerators will be required. The design of borehole-sondes is influenced by the arrangement of cryogenic apparatus and the technique of lowering the probes into the seafloor. Besides the possibility of probe penetration into the sediment on the bottom of the sea, the sample can also be transferred to the measurement system. (U.S.)

[en] Up to a weight of 1 ton NET in-vessel components will be handled by means of handling units which enter the torus through four horizontally arranged ports. The in-vessel handling unit (IVHU) consists of a radially movable carrier, an articulated boom extendable to about 25 m and suitable to reach any point of the torus. Three work units are optionally attachable to the end-frame of the boom. Components and equipment will be transferred by a carrier with telescopic arm. Plug handling devices are foreseen to open and close the entry ports. The equipment is housed in contained transfer units permanently attached to the ports and transferable via transport flasks to a service area. IVHU-carrier and articulated boom are connected by a combined yaw and roll joint. The 11 links of the boom are modular designed. Each of their yaw links is moved by two motor driven planetary roller spindles which actuate in series. The drives are externally arranged at the upper side of the links. Supply lines are routed inside the link boxes. A combined pitch and roll joint allows the end-frame adjustment. Three types of work units were investigated. An electrical master slave manipulator unit and two devices for the replacement of radiofrequency antennae and divertor plates. The IVHU can be controlled manually and automatically. Designing an experimental device for in-torus handling with an IVHU as a principal item has been launched. (author). 4 refs, 7 figs, 1 tab

[en] A fusion test facility such as TASKA can be operated successfully if the down-time can be kept at a level consistent with the assumed availability. The ease of maintenance is, therefore, an important consideration which impacts the conceptual design. This paper describes several maintenance concepts based on the TASKA design, selected on the basis of the frequency or complexity of the required maintenance

[en] In-vessel components of fusion reactors must be remotely replaceable. The necessary handling will be performed from inside the torus by means of work units. A major problem is to carry the work units inside the torus. One concept to solve this problem is to use an in-vessel handling unit based on an articulated boom. It is supported outside the torus and enters the torus through an entry port. Additional supports are not available. Then the work unit (manipulator unit, diverter handling unit or antenna handling unit), attached to the end-frame of the boom, is able to reach any point inside the torus. Therefore the boom consists of eleven links connected by yaw joints. Its stretched (unfolded) length is about 25 m. Due to the scissor type of design, the boom can be folded such that the required area to store it is only 10.25 x 3.2 m. The cross-sections of the links (except those staying outside the torus) are 350 x 1350 mm. In order to allow easy repair and exchange, the drive mechanisms for the joints and the necessary cable are located above the links. The resulting overall dimensions are such that the boom may pass the entry port having an opening of 650 x 1900 mm. The maximum load at the tip of the boom is about 3900 kg. It consists of the maximum payload of 1000 kg (which is the load of a diverter plate plus gripper) and the load of the diverter handling unit of 29000 kg. The design of the boom such that the stresses and strains are within allowed limits turned out to be a difficult task. It led to a boom dead load of about 25000 kg which is 25-times the payload. In this paper the structural mechanics assessment to find an appropriate design is described

[en] NET in-vessel components up to weight of 1 ton will be handling machines which enter the vacuum vessel through four horizontally arranged ports. Out of several options KfK investigated an in-vessel handling unit based on the system of an articulated boom. It is composed of a transport unit (carrier with articulated boom) and exchangeable work units. The boom is extendable to about 25 m and can reach any point within the torus. Carrier and articulated boom are connected by a combined yaw and roll joint. The 11 links of the boom are modular designed. A combined pich and roll joint. The 11 links of the boom are modular designd. A combined pitch and roll joint allows the adjustment of the end-frame. Work units investigated are an electrical master-slave manipulator unit and two devices for the replacement of divertor plates and radio-frequency antennae, respectively. An experimental device for in-torus handling with an IVHU as a principle item will be constructed. (author). 2 refs.; 8 figs.; 2 tabs

[en] NET, the Next European Torus, will be a fusion technology device attaining a burning Deuterium-Tritium plasma. Tritium environment and the high activation of the machine, the frequency and complexity of maintenance tasks give the maintenance analysis a crucial importance and determine the need to establish a comprehensive maintenance concept which is a basis for definition of a set of remote handling equipment, availability investigation as well as establishment of design standards. The NET maintenance concept is described. (author)