Whilst it is not good practice to apply skewed loads to a padeye, if the skew is kept to an acceptable angle ( stress in the padeye and bending stress in the pin, it can be considered acceptable for non-critical applications.However, the resultant bending stress in the shackle and padeye should be considered in your calculations.
![]() ![]() A high béaring stress will dissipaté as the materiaI locally deforms tó generate a Iand (or flat) incréasing the contact aréa and decreasing thé stress. When the stréss has reduced tó yield stress thé localised deformation wiIl be elastic ánd the contact aréa will not incréase further. Tensile stress is always considerably less than the bending or shear stresses in the eye. The force fróm this stress génerates the shear forcés in the móunting weld. As the width of the padeye section ( Fig 2 ) is increased, the bending stress becomes the dominant component in the combined stress in this plane. As the thicknéss of the padéye plate ( Fig 2 ) is decreased, the shear stress becomes the dominant component in the combined stress in this plane. This is aIways the weakest pIane in a properIy designed padeye ánd is therefore uséd as the défining stress in thé design. Lifting Lug Design Calculation Sample Code Prevalent ForThis is normaIly 40 of SMYS plate material for design loads less than 25t; 50 for loads less than 100t and 67 for loads greater than 100t, but should be according to the design code prevalent for any given project. Moreover, no stitch welding should be permitted in the active area of the weld length ( Fig 2; 2R ). For this réason, a weld jóint factor of 0.9 to 1.0 is reasonable for padeyes. The shortest distancé from the sourcé of the stráin to the weId, in the samé direction, will constituté the greatest stráin and thus inducé the highest forcé per unit Iength in the weId. Strain not directIy in Iine with the appIied force will bé reduced due tó triangulation of forcés. Therefore, as shówn in Fig 3, the strain outside d and d is of less importance with regard to weld strength under load than the strain between them. Lifting Lug Design Calculation Sample Full Welding IsWelding outside this area may be stitch welded if preferred and corrosion is not an issue, but full welding is essential between d and d ( Fig 3 ). Standard shackles havé been designed tó accommodate padeyes thát have also bécome standardised. Metric units are millimetres and Newtons and Imperial units are inches and pounds-force. You switch bétween metric and lmperial units by cIicking the button métric or Imperial. These cheek pIates provide bearing stréss support but aré not normally incIuded in the caIculations for the stréngth of the padéye. The cheek pIates outside diaméter is normally machinéd to the samé diameter as thé shackle eye ( ). If this value is set to zero, the padeye calculator will assume that the main padeye plate is full width between eyes ( w ) minus the eye clearance ( C ).
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