ASME HST-4−2016 pdf download.Performance Standard for Overhead Electric Wire Rope Hoists.
SECTION 4-0.1 SCOPE (a) This Standard establishes performance require- ments for electric wire rope hoists for vertical lifting service involving material handling of freely suspended (unguided) loads using wire rope withone ofthe follow- ing types of suspension: (1) lug (2) hook (3) trolley (4) base or deck mounted (does not include base- mounted winches of the type covered by ASME B30.7) (5) wall or ceiling mounted (does not include base- mounted winches of the type covered by ASME B30.7) (b) This Standard is applicable to hoists manufactured after the date on which this Standard is issued. This Standard is not applicable to (1) damaged or malfunctioning hoists (2) hoists that have been misused or abused (3) hoists that have been altered without authoriza- tion of the manufacturer or a qualified person (4) hoists used for the purpose oflifting orlowering people (5) hoists used for the purpose of drawing both the load and the hoist up or down the hoist’s own wire rope (6) hoists used for marine and other applications as required by the U.S. Department of Defense (DOD) (c) The requirements of this Standard shall be applied together with the requirements of ASME B30.16. Please also refer to ASME B30.16 for requirements pertaining to marking, construction, and installation; inspection, testing, and maintenance; and operation.
SECTION 4-1.2 HOIST DUTY SERVICE CLASSIFICATION 4-1.2.1 General Considerations Service conditions have an important influence on the performance of wearing parts of a hoist such as gears, bearings, rope, sheaves, electrical equipment, brake lin- ings, load- and lift-limit devices, and wheels. Careful consideration of the hoist duty service classifications described in this section will enable the user to evaluate the application and to obtain a hoist designed for opti- mum performance and minimum maintenance. If doubt exists regardinghoistselection, the hoistsuppliershould be consulted. Many factors enter into the selection of the proper hoist to perform a given function. Hoisting equipment consists of both mechanical and electrical components, and both must be considered when analyz- ing the service the hoist must perform. The factors thatinfluence the performance ofanyhoist include the following: (a) Load Distribution. The actual distribution or pro- portion of full and partial loads to be handled by the equipment, including lifting devices, has an important effect on the life of power transmission components. For example, ball bearing life generally varies inversely according to the cube of the load. A 2-ton (1 814.4-kg) hoist, operated at a mean effective load of 1 ton (907.2 kg), will have a ball bearing life eight times that of the same hoist used steadily at its rated load. (b) Operational Time. Operational time is the totalrun- ning time of the hoist per hour or per work period.ASME HST-4 pdf download.