Fluid flow devices for use with machines; pumps for dispensing flowable substances from containers; fluid flow machines; control valves for the control of gasses, liquids or moveable solids; flow control installations; valves for measuring fluid flow; installations for the handling of granular material; lifting machines for transporting materials; pneumatic machines for dosing materials in predetermined quantities; machines and apparatus included in this class, all being vacuum operated and for handling finely divided or granular materials for use in relation to oil refineries or the catalyst handling industry; apparatus for dedusting particulate, pellet or granular material; hoppers; separators for separating solids from a combined stream of gas and solids; catalyst handling machinery and apparatus; parts and fittings for the aforesaid goods