ASME B30.17-2020 pdf download

ASME B30.17-2020 pdf download.Cranes and Monorails(With Underhung Trolley or Bridge).
SECTION 17-1.9: STOPS AND BUMPERS
17-1.9.1 Runway Stops
(a) Stops shall be provided to prevent motion beyond the limits of travel of the bridge.
(b) Stops shall be provided at open ends of tracks, interlocking crossovers, track spurs, track openers, and track switches.
(c) Stops shall engage the bumper mounted on a power-driven bridge and withstand the forces applied by the bumpers.
(d) On a hand-operated bridge, the stops should engage parts of the crane other than the wheel. If a stop engages the tread of the wheel, its height shall be no less than the radius of the wheel.
17-1.9.2 TroLLey Stops
(a) Stops shall be provided to prevent motion beyond the limits of travel of the trolley.
(b) Stops shall be provided at open ends of tracks, interlocking crossovers, track spurs, track openers, and track switches.
(c) Stops shall engage the bumper mounted on a power-driven trolley and withstand the forces applied by the bumpers.
(d) On a hand-operated trolley, the stops should engage parts of the trolley other than the wheel. If a stop engages the tread of the wheel, its height shall be no less than the radius of the wheel.
17-1.9.3 Bridge Bumpers
(a) A power-operated bridge shall be provided with bumpers or other automatic means providing equivalent effect.
(b) Bridge bumpers shall have the following minimum characteristics:
(1) energy-absorbing (or energy-dissipating) capacity to stop the bridge when traveling with power off in either direction at a speed of at least 40% of rated load speed.
(2) capability of stopping the bridge (but not the load block or lifted load) at a rate of deceleration not to exceed an average of 3 ft/sec2 (0.9 m/s2) when traveling with power off in either direction at 20% of rated load speed.
(3) design and installation with a means of retaining the bumper in case of broken or loosened mounting connections. The retention requirement may be omitted for elastomeric bumpers if determined unnecessary by a qualified person.
(c) Multiple power-operated bridges operating on the same runway shall have contact bumpers that meet the requirements of (b)(2).
(d) Consideration should be given to providing bumpers with greater capacity for energy absorption (or energy dissipation) than that specified in (b)(1)
17-1.9.4 TroLLey Bumpers
(a) A power-operated trolley shall be provided with bumpers or other automatic means providing equivalent effect.
(b) Trolley bumpers shall have the following minimum characteristics:
(1) energy-absorbing (or energy-dissipating) capacity to stop the trolley when traveling with power off in either direction at a speed of at least 50% of rated load speed.
(2) capability of stopping the trolley (not including load block and lifted load) at a rate of deceleration not to exceed an average of 4.7 ft/sec2 (1.4 m/s2) when traveling with power off at one-third of rated load speed.
(3) a design and installation with a means of retaining the bumper in case of broken or loosened mounting connections. The retention requirement may be omitted for elastomeric bumpers if determined unnecessary by a qualified person.
(c) Multiple power-operated trolleys operating on the same bridge shall have contact bumpers that meet the requirements of (b)(2).
(d) Consideration should be given to providing bumpers with greater capacity for energy absorption (or energy dissipation) than that specified in (b)(1) and providing trolley end stops with corresponding increased strength when any of the following conditions are present:
(1) trolley has a maximum speed of 150 ft/mm (46 rn/mm) or greater
(2) trolley is on a remote-operated crane
(3) trolley is on a pulpit-operated crane
(4) location of the trolley end stops is obscured or uncertain
(5) crane is a cab-operated crane
SECTION 17-1.10: RAIL SWEEPS
(a) Bridge truck rail sweeps shall be provided in front of the leading wheels on both ends of top running bridge end trucks.
(b) Trolley rail sweeps shall be provided in front of the leading wheels on both ends of top running trolleys.