What types of power does a Category 1 or 4 crane generally use and what is its source?
What types of power does a Category 1 or 4 crane generally use and what is its source?
Category 1 and 4 Crane Power Types Category 1 and 4 cranes generally use electric or hydraulic power that is supplied by a diesel engine. A collector ring system conveys electrical current from the revolving portion of the crane to the lower crane structure.
What are the actions required if an asterisked item on the ODCL is found unsatisfactory during the pre use check of the crane?
What are the actions required if an asterisked item on the ODCL is found unsatisfactory during the pre-use check of the crane? Stop operation and notify engineering of the deficiency.
What is the operator’s main concern during crane operations?
Center the hook over the center of gravity of the load. While operating, the crane operator becomes concerned over the safety of the lift.
What may cause the bridge to skew?
Skew occurs in a crane system when the bridge fails to remain strictly perpendicular to the runway. Skew causes uneven and accelerated wear to the wheels and rails. This can result in differing diameters of drive wheels which in turn, can cause the crane to skew even more.
Which crane type typically has the highest combined capacity for reach and weight?
A tower crane is a modern make of the balance crane most commonly used on urban construction sites. When this crane is fixed to the ground during the construction period, it offers the best combination of lifting capacity and height.
What is the category of a jib crane with a capacity of less than 20000 pounds?
Category 3 cranes
Category 3 cranes are those with a certified capacity of less than 20,000 lbs.
Why is it important to have bent or dented crane boom members inspected and evaluated?
It is important to have bent or dented crane boom members inspected and evaluated because they can greatly reduce the strength of a boom, possibly resulting in sudden collapse of the boom. Gantry, Pendants, and Boom Stops Check the condition of the gantry, pendants, and boom stops.
At what rated capacity is a lift considered a critical lift?
75 percent
Critical lift means a lift that (1) exceeds 75 percent of the rated capacity of the crane or derrick, or (2) requires the use of more than one crane or derrick.
What is Bridge skew?
Skewed bridges are commonly used to cross roadways, waterways, or railways that are not perpendicular to the bridge at the intersection. Skewed bridges are characterized by their skew angle, defined as the angle between a line normal to the centerline of the bridge and the centerline of the support (abutment or pier).
What type of crane is used for high rise buildings?
Also known as sky cranes, aerial cranes resemble a helicopter and are used to carry large loads. Aerial cranes are typically used to transport materials to and from hard-to-reach places, like the tops of high-rise buildings.