Past, Present and Future of Hydraulic Valves

The number of hydraulic lifts in operation has been ever increasing during the course of the past years. Although originally conceived as goods lifts, hydraulic lifts today are used more and more as passenger lifts with travel speeds up to 1m/s (EN81-2) and more. Hydraulically operated passenger lifts are installed not only in residential buildings and industrial premises, but also in public buildings and centres, where they often take the shape of panoramic glass lifts. More and more lifts are installed in self-supporting and fashionably lined shaft frameworks subsequently added to buildings. Architects and lift manufacturers can give full play to their creativity regarding the design of lifts, including them in their architectural concept. Along with the increasing demand for hydraulic passenger lifts, greater stress has been put on travel comfort. Hydraulic lifts are required to offer a travel comfort that can be compared to the travel comfort of rope-traction lifts with speed-controlled direct current drives. Clients expect hydraulic lifts to offer a constantly high travel comfort unimpaired by load and temperature changes.