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ASME B30.21-2014 pdf download

ASME B30.21-2014 pdf download.Lever Hoists.
SECTION 21-0.1: SCOPE OF ASME B30.21 and bushings are press fit in their respective link plates Volume B30.21 includes provisions that apply to the construction, installation, operation, inspection, and maintenance of ratchet and pawl and friction brake type lever chain, rope, and web strap hoists used for lifting, pulling, and tensioning applications (see Figs. 21 -0.1 -1 , 21 -0.1 -2, and 21 -0.1 -3). The requirements for a lever hoist that is used for a special purpose, such as lifting personnel or drawing both the load and the hoist up or down the load chain, rope, or web strap when the lever hoist is attached to the load, and a specially insulated hoist used for handling energized electrical power lines are not included in this Volume. (see Fig. 21 -0.2-2). chain, welded link: a chain consisting of a series of inter- woven links formed and welded (see Fig. 21 -0.2-2). drum: the cylindrical member around which the rope or web strap is wound for lifting and lowering the load. friction brake: see load controlling mechanism . guide: a means to guide the load chain, rope, or web strap at the load sprocket (drum) [see Figs. 21 -0.2-3 and 21 -0.2-4, illustration (b)]. hazardous (classified) locations: locations where fire or explosion hazards may exist. Locations are classified according to the properties of the flammable vapors, liquids, gases, or combustible dust or fibers that may (14) SECTION 21-0.2: DEFINITIONS be present, and the likelihood that a flammable or com- bustible concentration or quantity is present (see ANSI/ abnormal operating conditions: environmental conditions that are unfavorable, harmful, or detrimental to or for the operation of a hoist, such as excessively high or low ambient temperatures, exposure to weather, corrosive fumes, dust laden or moisture laden atmospheres, and hazardous locations. block, load: the assembly of hook or shackle, swivel, bear- ings, sheaves, sprockets, pins, and frame suspended by the load chain, rope, or web strap. This shall include any appurtenances reeved in the load chain, rope, or web strap (see Fig. 21 -0.2-1 ). brake: a device for retarding and stopping motion of the load (see load controlling mechanism ). chain, load: the load-bearing chain in a hoist. chain, roller: a series of alternately assembled roller links and pin links in which the pins articulate inside the bushings and the rollers are free to turn on the bushings. Pins and bushings are press fit in their respective link plates (see Fig. 21 -0.2-2). Rollerless chain may be pro- vided on some equipment. chain, rollerless: a series of alternately assembled roller links and pin links in which the pins articulate inside the bushings with rollers on the bushings omitted. Pins NFPA 70). headroom (closed height): the distance between the saddle of the suspension hook and the saddle of the load hook when the load block is in its fully retracted position [see Fig. 21 -0.2-1 , illustration (a)]. hoist, lever: a manual lever-operated device used to lift, lower, or pull a load and to apply or release tension. hook latch: a mechanical device to bridge the throat open- ing of a hook. lift: the maximum distance through which the load hook can travel [see Fig. 21 -0.2-1 , illustration (a)]. load: the total superimposed force on the hoist load block or hook. load, rated: the maximum load that shall be applied to the hoist as specified by the manufacturer or a qualified person. load controlling mechanism: a mechanism that functions automatically to hold and control the load. In each of the following general types, a reciprocating force must be applied to the hoist lever to lower the load.
SECTION 21-0.4: REFERENCES The following is a list of publications referenced in this Standard. ANSI/NFPA 70-2011, National Electrical Code1 Publisher: National Fire Protection Association (NFPA), One Batterymarch Park, Quincy, MA 02169 (www.nfpa.org) ANSI Z535.4-2011, Product Safety Signs and Labels1 Publisher; National Electrical Manufacturers Association (NEMA), 1300 North 17th Street, Rosslyn, VA 22209 (www.nema.org) ASME B29.24-2002 (R2009), Roller Load Chains for Overhead Hoists ASME B30.10-2009, Hooks ASME HST-3- 1999 (R2010), Performance Standard for Manually Lever-Operated Chain Hoists Publisher; The American Society of Mechanical Engineers (ASME), Two Park Avenue, New York, NY 1001 6; Order Department: 22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007 (www.asme.org) ISO 7000:2012, Graphical symbols for use on equip- ment一Registered symbols ISO 7296-1:1991, Cranes – Graphical symbols – Part General Publisher: International Organization for Standardization (ISO), Central Secretariat, 1, ch. de la Voie-Creuse, Case postale 56, CH-1211 Gene ‘ve 20, Switzerland/Suisse (www.iso.org)

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