Designing and manufacturing overhead crane Omar Jaafar Hassan 199900307 Humaid AL-Marzoqi 200000181 Khalid AL-Hasani 199900342 Zayed AL-Katheeri 199900295 Advisor Prof. Kamal A.F.Moustafa
MaterialsHandling 1) Picking up the load 2) Transporting the load 3) Setting the load down
Importance of cranes 1.Avoid Congestion, Delays and unnecessary handling.2. Improve production operations . 3. Lower unit Materials handling Cost
Importance of cranes cont. 4. Reduce damage due to Materials handling. 5. Maximize space utilization. 6. Reduce the accident rate and severity of injury.
Type of cranes Mobile cranes Stationary cranes
Mobile cranes Mounted Cranes Crawler-Mounted Cranes
Mounted Cranes A wheel-mounted crane is mobile and flexible crane that can be driven on or off roads over rough terrain. Advantage: small working area.
Crawler-Mounted Cranes Stable base. The advantage: continuous work in remote areas
Stationary cranes Bridge Cranes Jib Cranes Gantry cranes Tower Cranes
Bridge Cranes The most important part are: girders, trucks, end ties, walkway and a drive mechanism
Jib Cranes Jib cranes consist of a horizontally mounted beam, not unlike a monorail, but that can swing in a semi-circle.
Gantry cranes Bridge crane but with girders that used in free space.
Tower Cranes Construction crew uses the tower crane to lift steel, concrete, large tools.
Main Components of Overhead Crane Girder Trolley Hoist Runway Rail
Safety Safety instruction Steps to inspect the crane safety Maintenance of the overhead crane
Safety Instructions Loads should not be suspended over personnel below. Avoid rapid movements in any direction
Safety Instructions Do not exceed the rated load capacity of the crane, hoist, chain, cable, slings, or other component.
Steps to inspect the crane safety Daily inspection Periodic inspection
Daily inspection Hoisting and lowering Trolley travel Bridge travel
PeriodicInspections Deformed, cracked or corroded members Loose bolts or rivets Cracked or distorted parts such as bearings, gears, rollers, etc Excessive wear on brake system parts
MaintenanceRequirements A preventive maintenance program based on the crane manufacturer’s recommendations must be implemented. Only specialist engineer may perform the required maintenance and repairs.
Designing Techniques • Newton’s Second Law approach • Lagrange’s approach
Newton’s Second Law approach Assumptions: Cable is mass less The payload is lumped with the hook and modeled as a sphere The system is frictionless
Newton’s Second Law approach cont.Payload kinetics Force balance in the horizontal direction
Newton’s Second Law approach cont. Payload kinetics Force balance in the vertical direction
Lagrange’s Approach Cont. Kinetic energy expression Potential energy expression