| 摘要 |
An enclosing vacuum chamber (1) comprises a fixed base (2), partly underground, connected by sealed joint (8) to a detachable upper section (3), optionally of modular construction (10, 11, 12, 13). The fabricated cylinder (5) has several sections (17, 18, 19, 20) welded end to end, starting with the top two (19, 20). Further sections are welded on, always from below, so that the electron gun(s) (22) and heat treatment induction coils (28), on fixed vertical adjusting rails (23, 29), always operate at about the same level (21), as does a central radial pressure unit (24, 25), maintaining alignment. To admit each new section, vacuum is broken and the upper chamber raised (6, 7). The cylinder stack, on a spacer block (16a), is rotated by a turntable (16) about the common vertical axis (I, I). |
