R 408.11833 Bridge bumpers; trolley bumpers; rail sweeps.

Rule 1833. (1) A crane shall be provided with bumpers or other automatic means providing equivalent effect, unless the crane travels at a slow rate of speed and has a faster deceleration rate due to the use of sleeve bearings, is not operated near the ends of bridge and trolley travel, is restricted to a limited distance by the nature of the crane operation and there is no hazard of striking any object in the limited distance, or is used in similar operating conditions. The bumpers shall be capable of stopping the crane, not including the lifted load, at an average rate of deceleration of not more than 3 feet/s/s (per second, per second) when traveling in either direction at 20% of the rated load speed. Bumpers shall meet both of the following requirements: (a) A bumper shall have sufficient energy-absorbing capacity to stop the crane when traveling at a speed of not less than 40% of rated load speed. (b) A bumper shall be mounted so that there is no direct shear on bolts. (2) Bumpers shall be designed and installed to minimize parts falling from the crane in case of breakage. (3) A trolley shall be provided with bumpers or other automatic means of equivalent effect, unless the trolley travels at a slow rate of speed, is not operated near the ends of bridge and trolley travel, is restricted to a limited distance of the runway and there is no hazard of striking any object in the limited distance, or is used in similar operating conditions. The bumpers shall be capable of stopping the trolley, not including the lifted load, at an average rate of deceleration of not more than 4.7 feet/s/s (per second, per second) when traveling in either direction at 1/3 of the rated load speed. Trolley bumpers shall meet both of the following requirements: (a) When more than 1 trolley is operated on the same bridge, each shall be equipped with bumpers or equivalent on their adjacent ends. (b) Bumpers or equivalent shall be designed and installed to minimize parts falling from the trolley in case of broken or loosened mounting connections. (4) Bridge trucks shall be equipped with rail sweeps that extend below the top of the rail and project in front of the truck wheels.