Differential pulley in collaboration with Richard and George Tangye. According to Richard Tangye's autobiography, the Weston differential pulley evolved from the Chinese windlass, with an endless chain replacing the finite length of rope. He claimed that many engineering firms conceded on the difficulty of efficiently disengaging the chain from the teeth as the pulleys turned, but his firm developed a "pitch" chain which solved the issue. Marketed as "Weston Differential Pulley Blocks with Patent Chain Guides", the pulley had good sales, namely, 3000 sets in 9 months. It was displayed in 5 sizes — from to — at the 1862 International Exhibition
Wire rope spooling technology the grooving on the drum. Alternatively, a sheave can be integrated and installed within the housing frame. In this case, the system can be set up anywhere around the drum. Oceanographic installations that spool rope up to 46 layers have demonstrated that level winders give synchronized and controlled spooling in the harshest, most testing conditions. Grooving systems for multilayer spooling can be carved onto steel shells that are mounted onto old drums, by either bolting or welding, as an outer sleeve. Called split sleeves, they can be retrofitted onto old drums or mounted on new drums to allow a future