ASME B30.3:2004 pdf free download.Construction Tower Cranes.
toiwr (mast): a vertical structural frame consisting of columns and bracing capable of supporting a superstructure with its working and dynamic loads and transmitting them to the supporting surface or structure.
tract iog (high strength) bolts: see lugh strength bolts.
trollei: the component of the crane that travels along the boom (jib) of a hammerhead tower crane and contains the upper load block.
trolhiisng: the motion of the trolley on the jib to locate the load hoisting mechanism at a working radius.
truck, travel: the assembly that includes a pivot, frame axle(s), and wheel(s) on which a crane rides on rails; see also bogie.
tu-blocking: the condition when the lower load block or hook assembly comes in contact with the upper load block.
a condition in which the operator of a crane is not at the operating controls.
wind induced rotation of a crane superstructure. when out-of-service, to expose minimal surface area to the wind.
wedge: a tapered wood or steel device used to provide stability to cranes during use as a climber. When the wedges are tightened against the four main legs of the tower, they convert overturning moments into horizontal forces to be resisted by the floor framing or slab (see Fig. 7).
SECTION 3-0.3: REFERENCES
The following is a list of standards and specifications listed in this Standard, showing the year of approval.
ANSI A14.3-1992, Safety Requirements for Ladders — Fixed’
ANSI A1264.1-1995, Safety Requirements for Workplace Floor and Wall Openings, Stairs, and Railings Systems’
Publisher: American Society of Safety Engineers. 1800 East Oakton Street, Des Plaines, IL 60018-2187
ANSI Z26. 1-1990, Safety Code for Safety Glazing Materials for Glazing Motor Vehicles Operating on bind Highways
3-1.1.5 Climbing Cranes
(a) A climbing schedule should be prepared in advance of the installation. The schedule should indicate each level at which the crane will be mounted for operation giving the locations of supports for both horizontal and vertical crane reactions and the maximum height to which construction can be carried before the crane must climb again.
(b) The means of transferring horizontal and vertical crane reactions to the host structure shall be reviewed by a qualified person. Wind effects for the height of crane mounting should be considered.
(c) Cranes shall not be climbed in concrete structures until the concrete at the levels at which horizontal and vertical supports are to be placed has reached sufficient strength to resist the crane reactions. It may be necessary to test concrete cylinders or cores or to use on-site testing techniques for this purpose.
(d) When climbing cranes are used, the integrity of the host structure shall be reviewed by a qualified person, for the effects of crane, load, and wind forces at each level of the structure.
(e) Wedging systems, when used to plumb the crane and to transmit horizontal reactions, shall be provided with means to prevent the wedges from working loose. Wooden wedges shall not be used unless recommended by the manufacturer. When wooden wedges are used, they shall be of hardwood.
(‘ Wedges shall be installed only at those portions of the tower that are designed to receive them or where provisions have been made for wedging in accordance with the manufacturer’s or a qualified person’s instructions. See para. 3-1.4J(f)(6).
(g) Initially, and after each climb, the crane shall be plumbed while balanced and then held in the plumbed condition by wedges or other means. Cranes should be plumbed to 1:500 (about 1 in. in 40 ft).
(Ii) Written climbing instructions should be kept at the site and all climbing operations shall be performed under the supervision of a qualified person.
(I) Before initial use and before each climb, load bearing members of the climbing and support system shall be inspected. Defects impairing the ability of a member to support load shall be repaired, or the member replaced.
(j) Before climbing, cranes shall be balanced in accordance with the manufacturer’s or a qualified person’s instructions.
