Screw jacks open doors for neutrons Linear actuation mechanisms are used for the generation of neutrons at a world-leading centre for research in physical and life sciences. The research centre ISIS is operated by the Science and Technology Facilities Council at the Rutherford Appleton Laboratory in Oxfordshire, England. The centre is considered to be one of the world's most successful pulsed spallation neutron sources. Neutron scattering is a vital research and analysis technique, used by scientists to probe the microscopic structure and dynamics of matter by providing controlled beams of neutrons and muons. These experiments encompass a wide variety of sciences including physics, materials science, engineering, chemistry, biology and earth science. Within the facility Power Jacks screw jacks have been providing a reliable linear actuation mechanism for the target station that permits the neutrons to reach the experimental instruments. High energy protons from the ISIS accelerator are sent to the target station where neutrons are generated by the spallation process and their characteristics are modified to make them usable for the neutron scattering experiments. The neutrons are produced when a 160kW proton beam hits a metal target made from thick tungsten plates. The resulting neutrons are directed into beam channels that surround the target and are the neutrons route to the scattering instruments. In total there are 18 beam channels and each has a shutter mechanism, which is opened if neutrons are required by an experiment. The shutters are made from steel and weight 30Te each and are required to actuate in a vertical plane on an individual basis. Providing the linear actuation on each shutter is 300kN E-Series metric machine screw jack type E1829 driven by a 7.5 kW geared motor. The screw jack has an inverted translating screw configuration with 500mm of stroke and 16mm lead driven by a 32:1 worm gear set. The standard design was customised to meet the exact customer installation and operation requirements. The special features ranged from large components such as a special lead screw to nuclear grade grease for screw and gear set lubrication. The screw jack is connected to the geared motor via a pin type lubricant free flexible coupling. The combination of the screw jacks gear type, screw type, gear ratio, screw lead and the additional gear set in the geared motor mean that the screw jack is self-locking to prevent the possibility of back-driving. The screw jacks have successfully operated over the last twenty years helping scientists to complete their experiments. Over this time the Power Jacks Group has provided a continuous after sales support service, which extends to maintaining spares availability should they be required. Speed Link InfoService Request more information by e-mail Reader Service No. Reader Number Email Address 01169    Tell a friend about this article:
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