20 February 2008
The world's most successful pulsed spallation neutron source is found in Oxfordshire at the ISIS facility in Harwell. ISIS supports an international community of over 2000 scientists who use neutrons and muons for research in physics, chemistry, materials science, geology, engineering and biology.
ISIS located in Harwell, Oxfordshire is the world's most successful pulsed spallation neutron source. These experiments encompass a wide variety of sciences including Physics, Materials Science, Engineering, Chemistry, Biology and Earth Science.
In these experiments controlled beams of neutrons and muons are used to probe the microscopic structure and dynamics of matter. The neutrons are channelled to the desired experimental instruments at the "target station". Part of the channelling process is controlled by a reliable linear actuation mechanism based on screw jacks provided by Power Jacks.
The target station receives high energy protons from the ISIS accelerator and by the "spallation process" generates neutrons that have their characteristics modified so that they are suitable for neutron scattering experiments. The protons arrive in a 160kW proton beam, which produces the neutrons when it hits a thick tungsten metal target plate. The neutrons are then channelled to the various scattering instruments by being directed into beam channels surrounding the target. There are 18 beam channels in total surrounding the target and each has a shutter mechanism that either allows or prevents neutrons from reaching the experiment. Each shutter is a 30 Tonne steel construction that is required to actuate individually in the vertical plane.
The linear actuation at each shutter is provided by a 300kN E-Series Metric Machine Screw Jack designed and manufactured by Power Jacks. The base model of screw jack used is the E1829. It is configured with a stroke of 500mm, lead screw pitch of 16mm, 32:1 worm gear set and driven by a 7.5kW geared motor that is coupled to the screw jack via a pin type lubricant free coupling. The basic screw jack was tailored to suit the exact requirements of the ISIS facility. Special modifications ranged form small features such as nuclear grade grease to main components such as the special lead screw. The complete package is self-locking by design to prevent the possibility of back-driving. This is due to the combination of the screw jacks screw type, screw lead, gear type, gear ratio and the additional reduction gear set in the geared motor.
Over the past twenty years the screw jacks have operated successfully allowing scientists to complete their experiments. During this time a continuous after sales support service has been provided by the Power Jacks Group, which includes maintaining the availability of spare parts, should they be required.
About Power Jacks
Power Jacks is a leading manufacturer for precision linear actuation, power transmission and mechanical jacking. The company is based in Scotland where its history for supplying high quality engineered product dates from 1903. The product ranges are detailed on the website www.powerjacks.com and include screw jacks, electric linear actuators, mechanical jacks, bevel gearboxes, planetary roller screws, reduction gearboxes, winches and rotary unions. They can be supplied worldwide singularly or as complete systems, whether in standard or specially engineered
Power Jacks Group
South Harbour Road
Tel: +44 (0) 1346 513131
Fax: + 44 (0) 1346 516827
SIS Pulsed Neutron and Muon Source
ISIS is a world-leading centre for research in physical and life sciences operated by the Science and Technology Facilities Council at the Rutherford Appleton Laboratory, Didcot, Oxfordshire, UK.
ISIS supports an international community of over 2000 scientists who use neutrons and muons for research in physics, chemistry, materials science, geology, engineering and biology. It is the most productive research centre of its type in the world.
Neutron scattering is a vital research and analysis technique in exploring the structure and dynamics of materials and molecules. It provides unique and complementary information to that available from synchrotron light sources.
ISIS Pulsed Neutron & Muon Source
Rutherford Appleton Laboratory