ASME HST-4:2016 pdf free download – Performance Standard for Overhead Electric Wire Rope Hoists
ceiling mounted: a type of hoist mounting where the hoist is mounted to the underside of a horizontal supporting surface. chain, hand: the chain provided to control movement of a hand-chain-operated trolley. contactor: an electromechanical device for opening and closing an electric power circuit. control actuator: a manual means at the operating station by which hoist or trolley controls are energized. control enclosure: the housing containing the electrical control components. cushioned start: an electrical or mechanical method for reducing the rate of acceleration of trolley motion. drum: the cylindrical member around which the rope is wound for lifting and lowering the load. hazardous (classified) locations: locations where fire or explosion hazards may exist. Locations are classified depending on the properties of the flammable vapors, liquids, or gases, or combustible dusts or fibers, that may be present, and the likelihood that a flammable or combustible concentration or quantity is present (refer to ANSI/NFPA 70). Class 1 locations: locations in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures. Class 2 locations: locations that are hazardous because of the presence of combustible dust. Class 3 locations: locations that are hazardous because of the presence of easily ignitable fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitable mixtures.
headroom: measured with the load hook at its upper limit of travel, headroom is the distance from the saddle of the load hookto the following locations (see Fig. 4-0.2-1):
(a) centerline of the suspension holes on lug- suspended hoists
(b) saddle of the top hook on hook-suspended hoists
(c) wheel tread line on trolley-suspended hoists
(d) supporting surface on base-, deck-, and ceiling- mounted hoists
(e) uppermost point of hoist on wall- and ceiling- mounted hoists
lift: the maximum vertical distance through which the load hook can travel, and is the total hook movement between its upper limit of travel and its position when at the lower limit of travel (see Fig. 4-0.2-1). liftingdevices, belowthehook: devicesthatare notnormally reeved onto the hoist ropes, such as hook-on-buckets, magnets, grabs, and other supplemental devices used for handling certain types of loads. The weight of these devices is to be considered part of the load to be lifted. limiting device: an electrical, mechanical, or electrome- chanical device for limiting the upward or downward travel of the load hook at the extremities of lift. This device may limit lift at any point within the extremities of lift, if designed to be adjustable. load: the total superimposed weight on the load block or load hook, including lifting devices. load hook: the hook used to connect the load to the hoist. load suspension parts: the means of suspension (trolley, hook, or lug), the structure or housing that supports the drum, the rope, the sheaves, and the load block. lug suspended: suspension of the hoist from a trolley(s) or permanent structure by means of bolt(s) or pin(s) through a rigid- or swivel-type lug(s). magnetic control: a means of controlling the direction and speed of the hoist and trolley by using magnetic contactors and relays.