Machining to microns - Custom-built HMCs machine beryllium segments for the James Webb Space Telescope

摘要

The largest lightweight beryllium optic that has ever been made will form a central element in the James Webb infra-red optimised Space Telescope (JWST), which is due for launch in June 2013. Designed to assist studying phases in the history of our universe, the optic has been machined in the USA, using a custom-built Mitsui Seiki horizontal machining centre. The Mitsui Seiki HS6A, which is available in the UK from the 600 Centre, Shepshed (Tel: 01509 600600), is one of eight installed in a climate-controlled factory at Axsys Technologies Inc, Cullman, Alabama. Noteworthy is the fact that these machines can position to just microns within the 1,300 × 1,000 × 1,000mm machining envelope. Each of the 18 beryllium segments, which are some 1.5m across, takes around a year to process, with each sequence of production involving rough and finish machining, chemical milling, heat treatment and inspection.