摘要 |
In apparatus for the manufacture of mineral insulated cable by a continuous process in which the tubular sheath is formed by bending and seam welding travelling metal strip, and insulating powder is fed through a powder delivery tube into the sheath while the latter is travelling vertically downwards, the conductor wires are introduced into the sheath down the outside of the powder delivery tube through guide means which may include, for a wire adjacent to the seam, a tube having an aperture in its wall adjacent to the weld area. Excess heat is removed from the weld area by either a wire or an air gap adjacent to the weld. When the sheath is formed of an oxidizable metal such as copper, means are provided for delivering a continuous stream of rare gas to the underside of the weld area. Various configurations of the powder/wire delivery system are described. |