| 摘要 |
An apparatus for raising and lowering a cutting tool within a decoking drum, a decoking system and a method of raising and lowering a decoking system cutting tool. Instead of using metallic ropes, chains, or a self-propelled gear-based approach, non-metallic belts are secured at respective ends to a crosshead and one or more counterweights to enable vertical movement of the crosshead that in turn permits vertical movement of the cutting tool throughout the height of the drum. A motorized pulley system controls the movement of the belt, and preferably avoids having the motor be carried by the crosshead. The belts on each pulley are preferably arranged as cooperative sets so that within each set, both primary load belts and secondary load belts are present. Enhanced engagement between at least the primary load belts and the pulleys promotes greater load-bearing capability, while the secondary load belts are sufficiently strong to ensure positional stability of the crosshead and decoking tool upon damage to or failure of one or more of the primary load belts. |
