| 摘要 |
<p>PURPOSE: To enhance the control of the thickness of a fire-resistant layer and workability by using an inorganic clay-like silicon compound as a material for forming an external fire-resistant layer and using a premolding which is nearly matching the shape of a connection part in the state of being halved in advance. CONSTITUTION: An inorganic fire-resistant layer 5 and a covering layer 6 are provided in a conductor connection pipe 4 press-fitted after a cable conductor in inserted into a branching part 4a to form a fire-resistant connection part. In the periphery thereof, a fire-resistant layer 8 is formed of an inorganic clay- like fire-resistant material, for instance, a silicon compound. At that time, laterally symmetrical halved premoldings 8 whose internal shape is identical to the shape of the fire-resistant cable connection part are prepared in advance, and it is integratedly put on the fire-resistant cable connection part from both sides. Thereby, the premolding 8 can be made by partially controlling the thickness of the external fire-resistant layer according to criticality as necessary, so that the workability in a site may be greatly enhanced.</p> |
