Oct 29, 2015 lifting analysis using compress software duration. At all lifting positions forces acting on lifting and tailing lugs are calculated as given below and maximum of acting force is taken for the analysis. All other items of interest will mainly depend on the. The analysis is similar to the weld above except that there is no interaction between tension and shear. The air force method of lug analysis is widely used in industry and is documented in the stress analysis manual of the air force flight dynamics laboratory fdl. Asme bth1 explicitly addresses the issues involved. Stress concentration factor on lifting lug boiler and. The spreadsheet you will purchase and receive is an excel file compiled in a. Pdf proposed design criterion for vessel lifting lugs in.
Finite element analysis of a lifting portable o shore unit a comparison between a shell and a beam model christian liebert maham rashid c christian liebert, maham rashid, 2015 masters thesis 2015. Calculate stressthe analysis stress is highly dependent on the mesh. The capacity is based on the maximum tensile stress at the base of the lug. Mar 21, 2011 the formula for combined stress seems to be an approximation for either the maximum principle stress or twice the maximum shear stress. When activated with lift lugs, the lift points are taken. The solution at the time of transportation, the pressure vessels needs to be lifted. Investigation of the application of adhesively bonded lifting lugs in. Design and analysis of lug joint in an airframe structure. Exe application file format identified by our icon image. This page gives a detailed discussion of methods to perform analysis of lifting lugs. A lug, also known as a lifting lug is essentially a plate with a hole in it where the hole is sized to fit a clevis pin.
The types of loadings to be considered here is axial load. Check it out, and as always you can download this, and many other excel tools at. Lifting lug design american institute of steel construction. Pressure vessel lifting and rigging analysis codeware. Finite element analysis of a lifting portable offshore unit. See appendix a for sample pages from esdu 91008 and esdu 06021.
This document shows analysis which verifies that the magnet can be moved safely by using the lifting lug. Jul 17, 2016 heres a simple sizing calculator for the most basic type of lifting lug. The bearing stresses and loads for lug failure involving bearing, sheartearout, or hoop tension in the region forward of the netsection in figure 91 are determined from the equations below, with an allowable load coefficient k determined from figures 92 and 93. Length of weld along side of lifting lugwl 80mm length of weld along bottom of lifting lugwb mm. From the printout above for the combined tension stress for the lug plate without any side load 0. This is important to minimize unwanted erection stresses or to prevent reversal of stress in certain portions of the lifted object.
When system operating temperature exceeds 150f and the pipe diameter is 4 inch or above. Design of vertical pressure vessel using pv elite software. Lifting lug stress analysis mechanical engineering. This work deals with lifting beams design and analysis. There are also several different configurations in the lifting lug software for different equipment and. Lugs are connectortype elements widely used as structural supports for pin connections. Ricker, pe, aisc engineering journal, fourth quarter1991 and its. The part 2 contains the new verification worksheets included in the version 2. Lifting lug graitec powerpack for advance steel 2015 duration. Hence, the structuresdesign was predicted to behave safe during lifting without inducing any permanent set.
Stress concentration factor on lifting lug jstephen mechanical 25 feb 15 02. Although this method is somewhat more complex than other lug analysis methods, it is. Therefore, design engineers are left without adequate technical guidance on this subject. Given that the lifting eye is 2 inches in diameter, and assuming the lifting hook to be at least 1. Bearing stress analysis the asme bth12008 code specifies the maximum allowable bearing stress on the pinlug interface to be 1. Several different styles of lifting lug are offered giving the user multiple options in selecting an appropriate lifting lug. Lifting lug analysis lifting lug rigging operations. Module 4 lifting and rigging sm 4 1 introduction a fire officer on a pumper was once asked why he ordered the pumper engineer to drive the 30,000 pound fire apparatus on a road that had a bridge with a 10,000 load limit. Dynamic factor when the movement of the precast unit is performed by lifting gear, dynamic forces that depend on the lifting gear used, appear.
For example, if you build a detailed fem to analyze a simple bracket, not only is it extremely inefficient but also considered as a lack of engineering judgement on your. Other esdu methods evaluate the stress concentration due to. We have updated the lug methods for our engineering textbook and one of the best explained and best laid out classic lug analysis comes from the us airforce stress manual, affdltr6942 and is explained in our online textbook here. Design calculations for lifting lug welded onto equipment, like pressure vessels etc.
Heres a simple sizing calculator for the most basic type of lifting lug. The analysis is similar to the weld above except that there is no interaction between tension. Variations in local sectional properties along the length of the vessel are considered. I used a bearing force in inventor and tried the same in solidworks with identical results. Sep 28, 2014 a stress engineers ability to perform classical hand calculations in structural analysis is one of the most important skills highly regarded in the stress engineering circles. The program will determine the ultimate strength of the lifting lug based on several checks and will apply the desired factor of safety to the strengths to attain allowable loads for the lifting lug. Strength of lugs under transverse load include strength analysis of the lug under inplane axial, transverse or oblique loading from a clearance fit pin. Different worksheets are reported for a complete verification of common configurations. Lifting lug design manual book lifting lug design manual lifting lug design manual getting the books lifting lug design manual now is not type of challenging means you could not solitary going taking into consideration books stock or library or borrowing from your friends to entrance them this is an unquestionably easy means to specifically get guide by online.
The design will provide safety against a lug failure, b pin failure. Lifting lug crosby shackles dynamic impact factor skew load factor typ factors used in lifts a an angle ap b d dia dia1 e f fws fx fxa fxb fy fya fyb h ip ix iy lw p pb per ph crosby shackles. Part 7 of 21 revision 1 to final safety analysis report for. When lifting and carrying precast elements, the lifting load has to be. The stress concentration factors were widely used in strength and durability evaluation of structures and machine elements. Conservatively, the analysis takes no credit for the structural rigidity of the. The lug analysis calculator allows for analysis of lifting lugs under axial, transverse, or oblique loading. For a single lug analysis, this will contain a complete analysis of the lug per asme bth1, considering each of the load cases entered by the user. For lifting, a lug arrangement is provided on the vessel. Lifting lug analysis free download as excel spreadsheet.
This failure mode involves bearing failure at the pinlifting lug interface. Modern steel construction steel questions or comments to. It also provides guidance related to impact and fatigue loadings more directly related to items such as lugs. The user can enter a desired factor of safety most applications, f. Lugs are connector type elements used as structural supports for pin connections. The codeware rigging analysis can be used with or without the lift lug option. A stress engineers ability to perform classical hand calculations in structural analysis is one of the most important skills highly regarded in the stress engineering circles. Pdf proposed design criterion for vessel lifting lugs in lieu of. Design and analysis of lug joint in an airframe structure using finite element method c. It provides bending moment, shear stress and bending stress diagrams as well as tabulated values at main vessel locations.
A lifting beam can also be used as a strong back to provide multiple lifting points on a relatively flexible object see fig. In my experience, accounting for the safety factors for lifting lug design using the aisc specification has been done in a much more ad hoc fashion. This calculator follows the air force method as documented in the stress analysis manual of the air force flight dynamics laboratory fdl. In some cases, however, the engineer may find the shear force too great and may be required to transfer the excess shear force to. Some lifting beams are made with a bottom lug aligned directly below the top lug so that, if the need. Solenoid lifting lug analysis stress mechanics strength. Lifting lug design mecalug software meca enterprises inc. This project deals with the design and analysis of a typical lug joint representative of an airframe structure applications. In some cases, however, the engineer may find the shear force too great and may be required to transfer the excess shear force to the foundation by another means. Fea, lugs, pin, margin of safety, vonmises stress, ansys. The fea results were used and fitted with selected generic equation. The spreadsheet verifies some configurations of lifting lugs and padeyes. Lifting lug design spreadsheet calculator engineers edge.
There is a spreadsheet for each of the individual failure modes. Torsion analysis of steel members,3 will be of value in torsion investigations. It is found that finite element analysis can provide important detailed stress distributions and limits for safety verification of lift components. From node 100 distance from node 1500mm lug contact widthw 200mm diameter of hole in lug dh 50mm radius of semicircular arcr80mm lug material x2crnimo1712 lug thickness 14mm offest from vessel od to centre of the holeoff 8mm.
The aisc manual of steel construction was used to determine the allowable stresses. Clearly in the design and analysis of a lifting lug for a vessel. Apart from the legal or contractual obligations that may exist, some general guidelines for when stress analysis should be done include. Detailed finite element modelling and analysis are conducted to analyze the lifting module and padeye connection. All the above mentioned items for the padeye part and weldment show a safe operation under the 3 swl applied load. I injection system a6810 permas field substructure.
The verification is performed considering the reference design and construction of lifting beams david t. In the past, the lug strength was overdesigned since weight and size requirements were for the most part unrestricted. When designing lifting lug, made from a square plate with a hole cut in the middle. Safety analysis report for certificate of compliance no. Do you apply stress concentration factor at the inside edge of the pin hole. The structural analysis performed in conjunction with the 30 foot drop accident will. That means that the primary unknown will be the generalized displacements. Designevaluation of overhead lifting lugs pdh online. Or do you only compare average normal stress across the remaining cross sectional area, fa to 0.
See the instructions within the documentation for more details on performing this analysis. With a safety factor of two, the allowable bearing stress is 15,000 psi. Pdf stress analysis evaluation of aircraft lugjoint. The officer responded to the question by saying that it was an emergency. Analysis of lifting beam and redesigned lifting lugs for 241az01a. Lifting lug proof test is carried out and here the linear analysis is done. Specifically, the analysis will show that the weld between the lifting eye and the solenoid body does not exceed the allowable stress, the stress at the lifting eye does not exceed allowable stress, and the bearing stress is acceptable. Lifting lug stress analysis mechanical engineering general. Aisc manual of steel construction asd, ninth edition, 1989. It may be permitted for the effects of warping stress to be discounted in a suitably approximate way, to analyse just the uniform torsion in members in the following cases. Shear lug design normally, friction and the shear capacity of the anchors used in a foundation adequately resist column base shear forces.
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