Module Lifting Lug Load Calculator

Formula Used

First convert module mass into lifting weight in kilonewtons. For tonne input, weight equals mass multiplied by 9.81.

Factored lift weight equals total weight multiplied by dynamic factor, impact factor, and tilt factor.

For four lugs, the calculator distributes load using center of gravity offsets in both directions. Each lug reaction equals factored lift weight multiplied by one longitudinal share and one transverse share.

Longitudinal share uses 0.5 plus or minus COG shift divided by lug spacing. Transverse share uses the same approach across the width.

Sling tension equals vertical lug load divided by sine of the sling angle from horizontal.

Horizontal component equals sling tension multiplied by cosine of the sling angle.

Design lug load equals maximum vertical lug load multiplied by the selected safety factor.

Bearing capacity equals padeye thickness multiplied by hole diameter multiplied by allowable bearing stress. Net section capacity equals padeye thickness multiplied by net width multiplied by allowable tension stress.

Utilization ratio equals design demand divided by entered capacity.

How to Use This Calculator

Enter the module weight and choose the correct weight unit. Then enter the number of lifting lugs and slings used in the lift.

Add the sling angle from horizontal. Lower angles increase sling tension quickly, so use the actual rigging geometry.

Enter center of gravity offsets and lug spacings. These values control how the load is shared across the lifting points.

Fill in dynamic, impact, tilt, and safety factors based on the lift plan or project requirements.

Enter lug geometry and allowable stresses for a quick screening check of bearing and net section tension.

Press calculate. The result section appears above the form and below the header. Review maximum lug demand, sling tension, horizontal force, and utilization ratios.

Use the CSV button for spreadsheet review. Use the PDF button to save the visible report.

Module Lifting Lug Load Notes

Module lifting studies need more than a simple equal load split. Real lifts often include offset centers of gravity, unequal geometry, and sling angles that change the force path. Because of that, a lug may carry much more than the average load. This calculator helps estimate those changes quickly using practical construction inputs.

The tool begins with total module lifting weight, then applies dynamic, impact, and tilt multipliers to create a factored lift weight. That value is shared to lugs using center of gravity offsets along both principal directions. The method is useful for planning checks, method statements, temporary works reviews, and preliminary engineering comparisons.

The output also converts vertical lug demand into sling tension. This matters because lower sling angles increase tension sharply. The horizontal component shown in the results helps users understand the side action delivered into the lug plate and local framing. A separate design load is then created using the selected safety factor.

For quick screening, the calculator checks simple bearing and net section tension capacities using entered plate dimensions and allowable stresses. These checks do not replace detailed design, weld design, pin checks, tear out review, local shell or beam verification, or code based lifting analysis. They do provide a useful first pass before deeper review.

Construction teams can use the report for lift planning discussions, temporary lifting studies, and internal design coordination. The graph and export tools make it easier to share results with engineers, fabricators, and site teams.