Barge Crane
Barge Crane
(OP)
Dear All,
I have a bidder's document to be reviewed regarding the subject. They offer a barged mounted crane with the following specification :
Barge Dimension = 150' x 50' x 10', draft=4.5' completed with ballast system
Crane = Crawler Manitowoc 4100 (Serial 41383) with LaticeBoom 200T capacity (Boom Length = 150ft and 180ft)
According to its load chart, the crane barge is able to lift safely 42 Tons of load at 45' working radius (150 ft boom length and 76.8 deg angle)with crawler extended.
Looking to the layout of crane barge, actualy the crane is not located at the center of barge. In fact, it is located 1.6 meters from barge center line.
What I need from you guys, if you ever have experience using such as barge mounted crane, please share to answer my question.... is it possible to lift 42T of load at 45’ working radius with that specification and layout..?
Looking forward for your response
I have a bidder's document to be reviewed regarding the subject. They offer a barged mounted crane with the following specification :
Barge Dimension = 150' x 50' x 10', draft=4.5' completed with ballast system
Crane = Crawler Manitowoc 4100 (Serial 41383) with LaticeBoom 200T capacity (Boom Length = 150ft and 180ft)
According to its load chart, the crane barge is able to lift safely 42 Tons of load at 45' working radius (150 ft boom length and 76.8 deg angle)with crawler extended.
Looking to the layout of crane barge, actualy the crane is not located at the center of barge. In fact, it is located 1.6 meters from barge center line.
What I need from you guys, if you ever have experience using such as barge mounted crane, please share to answer my question.... is it possible to lift 42T of load at 45’ working radius with that specification and layout..?
Looking forward for your response





RE: Barge Crane
It is certainly not overly large (our barge is 60m x 20m) but a lot will depend on where it is working: at sea? calm water? and whether he is lifting 360 degrees.
Is the crane 1.6m from the barge centreline along the short or long axis.
StephenA
RE: Barge Crane
My further question, is it valid if I assume that movement center gravity of crane barge due to 1.6m offset can be compensated by water ballast system as long as its trim can be maintained below 5 deg..?
Other thing, is there any rules state that crane must be located at barge center line along short axis..?
regards
RE: Barge Crane
Do you have any sample calculation regarding crane barge stability during lifting ? What is the limitation..? what is the acceptance criteria..?
regards
RE: Barge Crane
I will check up on the other questions
StephenA
RE: Barge Crane
A 42T @ 45'==>3,780,000'-lbs
S = lw^2/6 = 62,500 ft^3
p = M/S = 60.5 psf.
Its not naval arch but you get an idea of the barge capacity. Have seen the front awash during salvage operations (with a calm sea)
Best, Tincan.
RE: Barge Crane
If you really want to calculate whether the barge will be stable you need to calculate the position of the metacentre and then the metacentric height. My 1968 Fluid Mechanics for Civil Engineers has the formulae, so I imagine most books would and then it is a simple spreadsheet for all the various weights.
The metacentre is positioned at a distance I /V above the centre of buoyancy where I is the second moment of area of the waterline surface about the central axis and V is the volume of water displaced.
The metacentric height is the distance from the centre of gravity to the metacentre. The metacentre must be above the centre of gravity for stability.
I am not sure how to attach a file to a reply (or even if is possible?) but I could scan the pages if you wish.
StephenA
RE: Barge Crane
I am very glad if you could scan the pages and send to me via email at nasrul@badaklng.co.id
Thanks in advance.