| 摘要 |
<p>1497569 Automatic control of tension CONTINENTAL OIL Co 11 June 1975 [4 Nov 1974] 25070/75 Heading G3R Tension in a pipe-line is kept constant by automatically controlling the position of a "turn vehicle" 30, round which a 180 degrees loop is formed, in response to an electrical signal indicative of the pipe-line tension exceeding prescribed limits. The limits may be selected according to whether the end of the line is advancing, stationary, or withdrawing. The "vehicle" may be self powered but as shown it is moved by a winch 64 and the tension is measured by a transducer responsive to the pressure in an hydraulic piston and cylinder 68 connected in the winch cable. Similar transducers may be positioned at bends as at 60 to give an alarm and immobilize the control if tension bÞcomes excessive. The complete system comprises an hydraulic slurry transport pipe 26 and its supply 27, with pneumatic and electrical control lines 48, used in a mine with a work face 18. The pipe-line is supported along its length by wheeled, articulated "links" (42), Fig. 2 (not shown). The "turn vehicle" Fig. 4 (not shown) has a ramp to lift the wheels off the ground, the links being supported by, and sliding on, the inclined surface. The supports and the "turn vehicle" are described in Specifications 1428567 and 1497568 respectively.</p> |
