The Forgotten Padeye

December 1, 2007 at 6:43 pm 30 comments

Introduction

One thing often ignored by designers is: material handling. Figure 1 below is picture sent by my friend Rendra. It shows beams which were being transported by trailer truck. What’s wrong in Figure 1?

bad-handling2.jpg
Fig. 1. Structural beams transported by trailer truck.

The Forgotten Padeye

Besides being poorly secured to the trailer body, the beams have no padeye at all. Padeye, or sometimes called lifting lug, is a plate with hole attached to a structure, into which you can insert shackle or hook when you need to lift the structure. Figure 2 shows a padeye on undercarriage of Komatsu PC 2000 mining excavator. Figure 3 is a little bit different lifting lug integrated into the ribs in the superstructure of Terex RH 30-F mining excavator.

img_1864-padeye-komatsiu.jpg
Fig. 2. Padeye on undercarriage of Komatsu PC 2000 mining excavator.

img_2742-padeye-terex.jpg
Fig. 3. Lifting lugs integrated into ribs of Terex RH 30-F superstructure.

Transportation of Structures

Some designers only focus on what the structure does after it is constructed and ignore the other processes: fabrication, transportation and installation. Why padeye is very important? When we put padeyes into the design, we make sure the padeyes are welded to the part of structure which is strong and rigid enough so it will not deform or buckle when we lift the structure. We also make sure the padeye itself is strong enough to hold the pull force from the lifting hook or shackle. In this way, we can guarantee the safety during transportation and installation of the structures. We don’t want the structure collapse during lifting and squeeze someone to death.

What happen if the structures don’t have any padeye? We cannot expect the truck driver or the crane operator to have deegree in engineering. They will just lift the beams by any means they think OK and as fast as possible so they can go home earlier after work.

In the process, they probably attached hook or sling to parts of the structure which are not properly reinforced and have no strength at all. If you take a good look at Figure 1, you can see some plates are bent and permanently deformed due to mishandling. Can you imagine how pissed off the people in construction site who will receive the deformed beams? In workshop, with good collection of tools, you can fix the deformed beams. But in construction site, fixing that small deformed part is not easy due to limited tools. This costs extra time and delay in schedule.

Installation of Structures

When we install those beams, which serve as columns, we will need to erect them first. Most probably with crane. If the beams have no padeyes, the construction engineers will get creative and improvise by welding some plates or bars onto the beams as emergency padeye while they erect the beams. This will hurt the coating a bit. But even worse is: there is no strength calculation and safety measure. Who can guarantee the emergency padeye has sufficient strength and proper welding? Things always can go wrong and shit always happens

Never Forget the Padeye

Figure 4 shows the padeyes of LIMOV STM-50T mainframe during sand-blasting. You know we at LIMOV care for details and safety ;). If we provide some simple padeyes, the crane operator or construction engineer will easily spot them and understand that he should bolt the shackle into the padeye. This makes his job easier, faster and safer. It also keeps the structure in good condition. No buckled plates and scratched coating.

img_1709-padeye-limov.jpg
Fig. 4. Padeyes on mainframe of LIMOV STM-50T.

So, when you design something heavy, always pay attention to how it will be transported and installed. Never forget to put padeyes onto it. If you are not the designer, warn them when you see the padeye is forgotten. I wish you safe and reliable works always.

** End of Article **

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Entry filed under: Designer's Pitfall, Material Handling.

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30 Comments Add your own

  • 1. rendra  |  December 6, 2007 at 9:00 pm

    Ndra, for this case, i have warn the part’s supervisor who receive this support structure. But, they said: It’s okay rendra, it doesn’t matter, it still can be repaired correctly. The contractor give their guarantee. So, i can’t say another words, my mouth was locked.

    Hmm.., i just re-entering again your blog right now. And you had posted some writing. I’ll enjoy it with pleasure :D. Nice post bro.

    -still at site until next 1,5 weeks and without internet connection, except from my hp, hiks2.. 😦 –

    Reply
  • 2. .\Gojo  |  December 7, 2007 at 8:14 pm

    Question:
    Just how does the vendor load it onto the trucks in the first place?

    I suppose they are using cranes, but how does the sling -or whatever used- attached to the beams?

    ‘magnetic lifter’? *Sorry, I don’t know the actual term for this device.

    or perhaps there’s a place to put on some shackles?

    Reply
  • 3. isadikin  |  December 7, 2007 at 10:53 pm

    rendra: Hehehe, that’s our biggest problem: “high-inertia ignorance”. When a problem as simple as that is identified and given solution, still people don’t want to take simple action.
    You take care there in your “lost world”, bro. Tell us more about your project, OK?

    gojo: I think they used crane and some webbing slings wound around the beam. That’s the simplest way, Goi. I also do it sometimes with oversized webbing slings when there is no padeye. Magnetic lifter would be too fancy, hehehe. For shackle, I can’t see anything which can be attached to there.

    Anyway, regardless of what our boss says, let’s practice safety first principle when you and Rendra become construction boss 🙂 Let’s follow basic rule, educate people around us, and set good example.

    Reply
  • 4. ahmad dani  |  December 14, 2007 at 4:44 am

    nice examples.. many simple things could go worst if we could not handle it carefully, i will always remember this..! What a lesson..

    Reply
  • 5. Ironworker  |  June 28, 2009 at 1:28 pm

    1. If it has been loaded, it can be unloaded.

    2. It is not practical to put PADEYE just for 1 time installation purpose. If they are exposed when the building is finished, that will look stupid.

    3. All the iron-workers and crane operators have been lifting structural beams before you and I were born with the way they are now – its proven and normal practice.

    4. Always use certified beam clamps, slings, and any other necessary clamping and lifting tools when performing work and stay clear when objects are lifted.

    Reply
    • 6. Adam  |  June 8, 2010 at 3:59 am

      So what your saying is that, lets keep doing it the way we’ve been doing it. Hey why not, a beam hasn’t dropped on your head yet.

      I’m sure the families of dead construction workers will find solace in your statement. Who would want to use modern design tools like FEA anyways? RESPONSIBLE ENGINEERS WOULD.

      Ignorance is bliss. Just keep being ignorant, but you better keep at least one eye looking up at that beam flying over your head.

      Reply
      • 7. James G  |  January 20, 2012 at 10:31 pm

        Look up beam clamps in your search engine. There are lots and they are perfectly safe and properly tested. No need to be so nasty when the man speaks the truth and there is no more danger than if padeyes are present. Yes you read that right, too often padeyes and holes have no supporting or inadequate calcs. With beam clamps this is not an issue. Even if beam clamps are not used there are recognised methods for slinging without incident. A rigger is an actual trade with training! They know these things. The far more important issue in the picture above is the lack of restraint in transit.

  • 8. adamu kgoh enemona  |  December 14, 2009 at 7:20 pm

    please could you send me spreadsheet for padeye/spreader bar design….i will be very glad to have as many literatures on the design of padeyes and spreader bar.
    regards
    n.b(my email is wooldof@yahoo.com)
    sincerely

    Reply
    • 9. isadikin  |  December 26, 2009 at 12:29 am

      Check your inbox, mate. 🙂

      Reply
      • 10. lee  |  September 2, 2010 at 5:17 pm

        Hi,

        Please could you send me also spreadsheet for padeye design. I will use it in the design. I need sample calculations, please help. here is my email ad: saromines_lee23@yahoo.com

        Thanks and regards

      • 11. green~tea  |  October 18, 2010 at 3:39 pm

        Would appreciate if you could send me at jeyz2002@yahoo.com excel spreadsheet for padeye design calculation.

        Thanks

      • 12. ezeudo  |  February 22, 2011 at 7:01 pm

        Please isadikin will appreciate if you send me the spreadsheet for padeye design many tnx.

        my email is udo_bkink@yahoo.com

    • 13. ezeudo  |  February 22, 2011 at 7:06 pm

      Hello Adamu, please could you send me padeye design spreadsheet. many tnx. udo_blink@yahoo.com

      Reply
  • 14. roz  |  February 3, 2010 at 4:11 am

    i have to design a padeye out of steel for a lifting beam. i need the equations needed to calculate all that needs to be calculated. please help.

    Reply
  • 15. chad  |  June 10, 2010 at 11:47 pm

    Yes, I need to design a pin connection which is besically a pad eye too. Can you send me calculation sample and the spreadsheet? pls..

    Thanks

    Reply
  • 16. Suman Kar  |  July 16, 2010 at 8:39 am

    I am currently engaged with a 5500 ton lifting with 8 padeyes. Can anybody send me padeye design excel sheet and if any literature available.
    Thank you.

    Reply
  • 17. Suman Kar  |  July 16, 2010 at 8:40 am

    I am currently engaged with a 5500 ton lifting with 8 padeyes. Can anybody send me padeye design excel sheet and if any literature available.My email is sumankar2007@gmail.com

    Thank you.

    Reply
  • 18. G.Moorthy  |  July 31, 2010 at 7:41 pm

    Can you plese help me to get me the fallow details standard Book for padeye,Which will contain the fallwing details about size , capacity,Meterial details etc.

    Reply
  • 19. abhisekh  |  October 27, 2010 at 6:09 pm

    please send me excel file for design of lifting lug and spreader bars my mail id is trustmeasfrnd@gmail.com

    Reply
  • 20. Omkar  |  March 3, 2011 at 11:22 am

    Hi,
    Can anybody send me the design calculations for the padeye design used for heavy lifts?
    Email id :- om.bapat@gmail.com

    Reply
  • 21. syamsul  |  May 9, 2011 at 10:25 am

    I am currently engaged with a 8500 ton lifting with 8 padeyes. Can anybody send me padeye design excel sheet and if any literature available.My email is azmeenizam@yahoo.com

    Thank you.

    Reply
  • 22. renny  |  July 21, 2011 at 10:11 pm

    great discussion guys, I need to put some padeyes onto a riser pipe 10Tons, could someone send me a copy of the excell spreadsheet with padeye design.

    Thanks.
    reytirbany@yahoo.com

    Reply
  • 23. vivekkumar  |  December 27, 2011 at 9:10 pm

    Hi,
    Can anybody send me the design calculations for the padeye design used for heavy lifts?
    Email id :- margamvivekkumar@gmail.com

    Reply
  • 24. cromagnum  |  January 20, 2012 at 3:38 am

    The Beams in the first picture (besides the lack of straps) also did not have adequate cribbing between them to ensure a secure load, hence the crushed angle frames.

    As for padeyes in structural steel columns, thats not a practice in the USA for several reasons.
    1) its not required
    2) Somewhere, some engineer would require them when they interfere with other parts of the construction. (Murphys law)
    3) it adds additional costs to a very competitive industry. Every pound of steel, every hole, and every weld costs money, when there is little profit to start with.
    4) It actually is slower for the erectors to use that, they use a chocker sling at the top to lift the column uprght, set it on the anchor bolts (loosely tighten) and then climb a ladder to release the chocker. The less time in the air releasing the column, the faster the building goes up.

    Now if someone designed a better/cheaper way to erect columns, then you have an industry at your fingertips.

    Reply
  • 25. soogrim balraj  |  January 26, 2012 at 6:15 pm

    hi this is balraj. and im sending my email address for you lisabalraj@hotmail.com

    Reply
  • 26. soogrim balraj  |  January 26, 2012 at 6:16 pm

    hi this balraj. from this email addres lisabalraj@hotmail.com

    Reply
  • 27. Eliezer  |  February 15, 2012 at 12:14 am

    Hey,

    Could you please send me the padeyes spreadsheet? Much appreciate it

    Reply
  • 28. Jonbell  |  February 17, 2012 at 8:56 pm

    I too would be pleased to have the spreadsheet

    Reply
  • 29. Vionioult  |  September 4, 2014 at 9:53 pm

    jean luc boeuf quimper

    Reply
  • 30. Vibin  |  August 25, 2015 at 7:55 pm

    Hi,
    Can anybody send me the design calculations for the padeye design ?
    Email id : pr.vibin@gmail.com

    Reply

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