Overhead Crane Types

In planning a crane building, and in selecting overhead cranes, it is important to consider future operations that may increase loading and service requirements in addition to present operations. Be certain to plan for both crane building and cranes to satisfactorily meet the increased service conditions that may arise in the future. This planning effort will minimize the possibility of overloading or of placing the structure in a more severe classification than intended.

There are many types of cranes in use today to meet material handling requirements.The types described here include those cranes currently being supplied by major crane manufacturers support of these crane types usually affects the design of the building in which the crane is installed.

Top Running Cranes

Top-running bridge cranes are characterized by bridge end trucks bearing on top rails attached to the runway beams. Top-running bridge cranes are generally used for more severe applications with heavier loads and high service classifications. They are generally applicable when one crane isle extends the full width of a building aisle, and they are frequently used where high travel speeds are required. In comparison to underhung cranes, top-running cranes usually provide greater hook height and clearance below crane girder. Top-running bridge cranes may be single girder, double girder, or box girder. Single girder cranes are generally used on shorter spans and lower capacities or service classifications. The trolley of a single girder crane is suspended from the girder. Cranes are normally operated by a pendant pushbutton station suspended from an independent track or radio remote.

Double girder cranes

Double girder cranes are generally used on moderate spans and higher capacities or service classifications. The trolley of a double girder crane usually bears on rails attached to the upper flange of the crane girders. Low headroom double girder cranes are available that are designed to produce maximum clearance beneath the bridge.

Box girder cranes are generally used on larger spans and high capacities or service classifications. The trolley bears on rails attached to the upper flange of the crane girders. Box girder cranes are normally operated from a pendant pushbutton station suspended from an independent track or a radio remote.

Underhung bridge cranes

Underhung bridge cranes are characterized by the bridge end trucks being suspended from the lower flange of the runway beam. Underhung bridge cranes are generally used for less severe applications with lighter loads and lower service classifications. They are frequently used where multiple crane aisles are required in a building aisle,where the crane aisle is only a portion of the building aisle, and when materials must be transferred between building aisles. In comparison to top running cranes, underhung cranes usually provide greater hook cover, clearance beneth the runway beam, and clearance for overhead obstructions.

Underhung bridge cranes may be single or double girder with the trolley suspended from the lower flange of the girder or girders. The power source of the hoist, trolley, or bridge may be hand geared or electric. Electric powered cranes are normally operated by a pendant pushbutton station suspended from the hoist.

1. GENERAL RANGE OF CRANE TYPES

2. Crane Type Power Source Description Span or Reach Capacity

3. Underhung 1. Hand Geared Single Girder 10’ to 50’ Spans ½ to 10 Tons

4. 2. Electric Single Girder 10’ to 60’ Spans 1 to 10 Tons

5. Top-Running 1. Hand Geared Single Girder 10’ to 50’ Spans ½ to 10 Tons

6. 2. Electric Single Girder 10′ to 60′ Spans ½ to 10 Tons

7. 3. Electric Double Girder 20′ to 60′ Spans 5 to 25 Tons

8. 4. Electric

9. Box Girder

10. Pendant-Operated

11. 4-Wheel End Truck 20′ to 100′ Spans

12. 5 to 25 Tons

13. 5. Electric

14. Box Girder

15. Radio Controlled

16. 4-Wheel End Truck 50′ to 100′ Spans

17. Up to 60 Tons

18. 6. Electric Box Girder

19. Radio Controlled

20. 8-Wheel End Trucks 50′ to 100′ Spans Up to 100 Tons

21. Jib Cranes 1. Hand Geared or Electric Floor-Mounted

22. 280 to 360 8′ to 20′ Reach

23. ¼ to 5 Tons

24. 2. Hand Geared or Electric Column-Mounted

25. 180 8′ to 20′ Reach ¼ to 5 Tons