I am doing a hand calculation to find the percentage loading in 4 lift padeyes on a structure which is 2000mm L x 1500mm W x 1200mm H. Attached image shows a structure with the COG exactly in the center. This would then have a percentage load on each liftpoints/padeye as 0.25 (which is 25%, as there are 4 padeyes A, B, C, D). My question is if the COG is offset from the center by 150mm and 50mm in the horizontal plane, towards one liftpoint/padeye (for example say toward liftpoint/padeye A), how can we calculate the percentage loading on each lift point? Thanks in advance.
You have 4 unknowns in the sling load in each leg. You can set up a system of equations, sum in x direction = 0, sum in Y direction = 0 and sum in z direction = 0. The fourth equation is the skew effect, but in answer to your question, sum of vertical loads in one pair of diagonal slings - 50% total lift weight (ie a skew factor of 1.0). You can then solve for your sling forces and then compare the %'age difference in each leg due to your offset.
Without using load eveners (pulleys or levers) on the support cables you can easily have 100 percent of the load on only two cables. If you rig 4 cables of equal length as shown in the OP. The load will tilt when lifted so the cg is under the hook, and one cable will have zero tension. The problem is indeterminate without some extra rigging.
Rather concerned that you are distributing 25% load on each when requirements for the design of a 4 leg sling, in accordance with EN 13414-1 : 2008, Steel wire rope slings - Safety - Part 1: Slings for general lifting service. This code is recognised as complying with the EEC Machinery Directive. This method is intended to be used for a equal leg length sling, but can be used for unequal leg length slings. see attachment.
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Metal 3D printing has rapidly emerged as a key technology in modern design and manufacturing, so it’s critical educational institutions include it in their curricula to avoid leaving students at a disadvantage as they enter the workforce. Download Now
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now
Talk To Other Members
RE: Percentage Loading in Lift Padeyes
To answer your question see attachment. Basic statics I'd say.
RE: Percentage Loading in Lift Padeyes
RE: Percentage Loading in Lift Padeyes
RE: Percentage Loading in Lift Padeyes
RE: Percentage Loading in Lift Padeyes