ASME B30.3-2019 pdf download.Tower Cranes.
3-1.1.2 Where Stability Governs Lifting Performance (a) Each load rating shall be determined for the least stableconfigurationcoveredbytherating.Forloadsatany operating radius, stability is affected by the length of the jib or luffing boom, counterweight arrangement, and tower height and arrangement. The manufacturer shall take these configurations into account when establishing load ratings. (b) Wind forces shall be determined using the maximum in-service wind velocity, as specified by the manufacturer or by a qualified person, and shall be applied in the direction least favorable to stability. (c) For cranes designed to travel with load, inertial forces and forces induced by the maximum allowable track variation from level, as specified by the manufac- turerorbyaqualifiedperson,shallbeconsideredinestab- lishing the load ratings. (d) In addition to the above, the following stipulations shall apply to establishing the load ratings: (1) Incipienttippingexistswhenthealgebraicsumof the overturning (tipping) moments equals the sum ofthe stabilizing moments. (2) The crane is mounted level, except as in para. 3-1.5(j)(1)(-c), but for those cranes that exhibit significant elastic deflection due to dead, live, wind, or dynamic loads, the effect of such deflections on stability shall be taken into account. (3) Lifting attachments that are a permanent part of the crane in its workingcondition shall be consideredpart ofthe load for stability calculations, whether or not such attachments are a part of the published load ratings. (4) The manufacturer or a qualified person may specify use of stabilizers or ballast to achieve stability.
3-1.1.3 Where Structural Competence Governs Lifting Performance (a) For each stipulated operating radius, the manufac- turer or a qualified person shall ascertain thatthe crane is capable of supporting the rated loads without stresses exceeding predetermined acceptable values. Dynamic effects associated with hoisting and slewing shall be considered. Wind shall be taken in the least favorable directionandatthemaximumin-servicevelocity,asspeci- fied by the manufacturer or a qualified person. (b) The manufacturer or a qualified person shall eval- uate structural competence for the least favorable config- uration and operating conditions covered by given load ratings. Under any condition of loading, stresses may also be affected by the jib or luffing boom length, counter- weightarrangement, towerheightandarrangement, hoist line reeving, and hoisting speed range. (c) For cranes designed to travel with load, inertial forces and forces induced by maximum allowable track variation from level, as specified by the manufacturer or a qualified person, shall be considered in establishing structural competence. (d) In addition to the above, the following stipulations shall apply to proof of competence determinations: (1) The crane is mounted level, except as in para. 3-1.5(j)(1)(-c), but for those cranes that exhibit significant elastic deflection due to dead, live, wind, or dynamic loads, the effects of such deflections shall be taken into account. (2) Lifting attachments that are a permanent part of the crane in its workingcondition shall be consideredpart ofthe load for rating calculation purposes, whether or not such attachments are a part ofthe published load ratings.ASME B30.3 pdf download.