雙塔俯仰式纜機英文文獻翻譯-文庫吧
2025-04-17 15:09 本頁面
【正文】 the control systems see also the Electrical documents of ABB Company. The crab traversing winch is driven by a DCmotor that allows for an infinitely variable speed regulation. For physics reasons he acceleration shouldn39。t be much beyond 0. 75 m/s2 . Thereof result acceleration and braking times of approx. 10 seconds (braking torque about 6000 Nm) 。 respective path is approx. 37:5m. With missioning operations the mechanical brake shall be set in a way that the loaded crab will e to be stopped after at the latest 12 seconds (braking torque approx. 6000 Nm). Because of the varying loads will result otherwise with merely mechanical braking (emergency) shorter braking times. Normally the torque having been generated by the motor is transmitted over a 2groove drive pulley to the crab traversing rope. Here one has to check periodically for ensuring39。an uniform running in the two grooves (see chapter Maintenance). Between the two grooves` the crab traversing rope is led over the return pulley。 at the shaft of which is also fitted :the screwtype limit switch and the position indicator, just also the tachometers for measuring the speed and for control of a possible over speed. Although the screwtype limit switch and the position indicator are driven by the nondriven return pulley, it is unavoidable that after a duration of operation occurs a certain missindication, so that the correction will have to be made (see chapter Traversing Limit Switches and Position Indicators). For safety reasons have been installed, however, at the first and at the last rope carrier additional limit switches for monitoring the crab speed. Since these limit switches cannot shift out of their set position, the signal is absolute. Finally the crab traversing is then stopped by a lever limit switch attached at each end of the track rope. The tachometer for monitoring a possibly occurring over speed disconnects the crab traversing gear at 115% rated speed by emergency off. For providing the operation and maintenance team with information concerning the plant output, the crab traversing gear is equipped with an operation hour39。 s counter and a cycle counter. Here the operation hours counter is detecting the time in which the crab traversing motor is working, and the cycle counter the number of traversing runs. Therefore the cycle counter is set in a way that after each motor operation time of about 10 seconds in one direction another half cycle is counted up. In case the travel is interrupted and continued, thereafter in the same direction no new half cycle will be added. In case the direction of travel is
畢業(yè)設(shè)計相關(guān)推薦
鄂ICP備17016276號-1