The Little Rock District, Corps of Engineers is requesting quotes for a jib crane system with hoist.

Deadline: 15 August 2007

Contact: Juanita Granger, 501-324-5720, Fax 501-324-5196, nita.a.granger@usace.army.mil

Furnish a complete 480volt 3 phase, remote control Jib Crane system consisting of a free standing jib crane and a minimum of 3 ton capacity electric cable hoist. The crane will provide coverage for a circular work area about the mast, and must be capable of 360 deg. continuous rotation. Crane rotation will be motorized. Rotation of boom along with travel and lift of hoist will be by wireless remote control. The jib crane system shall be designed for outdoor installation and operation. All electrical and mechanical parts shall protected from the weather and in suitable enclosures. Attached drawing is for reference and shows required installation. Drawing shows boom height and length requirements.

SPECIFICATIONS:

1. Free standing jib crane will consist of a stationary mast (Pillar) about which a boom and box-style head will rotate. The crane will provide coverage for a circular work area about the mast, and be capable of 360 degree continuous rotation. The rotating head will be motorized and rotate at a max speed of one-half revolution per minute. Rotation will be by remote control.

2. Hoist shall be minimum rated capacity of 3 tons with a lifting and lowering range of minimum 84 ft. Hoist shall have two hoisting speeds and shall be capable of hoisting and lowering the rated load at a high speed of 30 feet per minute (fpm) The trolley shall be motorized with two operating speeds and shall be capable of moving the rated load at a high speed of 30 fpm. Low speeds shall be one quarter to one third of high speeds. Actual speeds shall be within plus or minus 15 percent of those specified.

3. Electric wire rope hoist shall be designed for outdoor installation and shall contain enough wire rope for a minimum 84 ft drop.

4. Hoisting ropes shall be improved or extra improved plow steel, regular lay, uncoated, 6 by 37 class construction, with an independent wire rope core. Provide proof of wire rope breaking strength test report.

5. Sheaves shall be steel or ductile cast iron. Pitch diameter of running sheaves shall not be less than 16 times the rope diameter. Pitch diameter of non running sheaves shall not be less than 12 times the rope diameter.

6. Drum shall be steel or ductile cast iron. Pitch diameter of the drum shall not be less than 18 times the rope diameter. Not less than two dead wraps of the hoisting rope shall remain on each anchorage when the hook is in its extreme low position.

7. Motors: (480 volt, 3 phase) Hoist and Trolley motors shall be two speed AC squirrel cage induction type. Motor insulation shall be Class B minimum. Provide totally enclosed non-ventilated (TENV) motor enclosures. Maximum motor speed shall not exceed 1800 rpm. Rotation motor shall be one speed to allow rotation of rotating head at a max speed of one-half revolution per minute.

8. Runway electrification shall be of the flat festooned type.

9. Controls: Provide two speed magnetic control for the hoist and trolley and one speed control of the rotating head. Supplier may provide for variable frequency drive as an option for control of the trolley, hoist and rotating head. Provide upper and lower limit switches which de-energize the hoist motor. Hoist shall have an electro-mechanical holding brake and a mechanical load brake, each capable of holding 130 percent of the rated hoist capacity. Hoist holding brake shall be capable of being released to test the load brake. Provide trolley with an electro-mechanical brake. Provide trolley brake with a minimum torque rating of 100 percent of the drive motor rated torque.

10. Pendant Pushbutton Station: Hoist, trolley, and head rotation shall be remote controlled from three separate locations, the crane foundation, the next lower level (26 ft below crane foundation), and the lowest level (approximately 84 ft below crane foundation). Jib Crane system shall be provided with two remote wireless pendants. Arrange pushbuttons in accordance with ASME B30.11 recommendations.

11. Painting system: Painting shall be manufacturers standard. Provide a primer and a finish coat. Blast clean all components prior to painting. Finish coat shall be an epoxy formulated for marine environments.


Jib crane drawing Jib crane drawing Jib crane drawing
Related Files
Jib crane drawing