| 摘要 |
<p>Valve for regenerating the air flow for drawing a telecommunication cable (3) into a buried conduit (1) by means of a pig (mole, rabbit, ferret) (6) fixed to the end of the cable. The valve includes a two-part fixed casing (15) in which is mounted a spool comprising two caps (24, 32) separated by a sliding orifice-plate (41). The two caps are formed by two half-rings (25, 26) on the one hand and (33, 34) on the other hand, one of which includes an inclined duct (27, 35) which brings or does not bring a compressed-air inlet and outlet chamber into communication with an axial passage channel (28). The sequential operation of the moving parts of the spool is performed by the cable-pulling pig which includes two protuberances (50, 54), so as to exert a thrust force on the pig upstream and then downstream of the valve, before the sections of the conduit, which are connected by the valve, are set to open air after the pig has passed. <IMAGE></p> |
