| 摘要 |
In a method of manufacturing mineral insulated electric cable in which introduction of mineral insulating powder into, and compaction of the powder in, an advancing metal tube from which the cable sheath is formed can be more rapidly achieved than hitherto, the powder is injected into the metal tube under the pressure of a gas via a powder delivery tube which extends into the metal tube and through which the conductor rods are fed so that the powder fills the space around the rods within the metal tube and is partially compacted under gaseous pressure. Gas is expelled from the powder delivery tube through filtered outlet ports disposed in the wall of a fitting secured to the downstream end of the delivery tube and effecting a filtered seal with the advancing tube downstream of the ports. Preferably, the advancing metal tube is disposed horizontally and is continuously formed by bending an advancing ductile strip into tubular form and welding the edges of the advancing strip together.
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