Casted Lifting Hooks?

[kranmeste]

Hi all,

I have a task to design a specific lifting hook, and the total quantity we need per year is 20pcs.

Now to the specifics. Many of the lifting hooks that are purchased as standard parts from various manufacturers like Crossby, ELD etc etc, are all forged parts. They very often comply to the standard EN 1677-1 or 2 or 3 and so on. But as i wrote, these standards are for forged parts only.

Due to that i only need 20pcs per year i am looking in to casting the lifting hooks instead. But until now i have not been able to locate any standards that mention anything about casted hooks that can be used for suspended loads.

If any of you have any ideas or specifically know about Standards for casted lifting hooks, any information about this would be appreciated.

Thank you.

Regards
Jakob

 

[robyengIT]

Google : cast iron lifting hooks

 

[SAIL3]

personally, I do not trust casting lifting hooks ,unless, combined with strict quality control and perhaps testing....porosity(imperfections) would be my major concern.....

 

[robyengIT]

agree with Sail3, especially for heavy duty

 

[GregLocock]

I suggest proof testing each one to 4 to ten times the SWL. Actually I don't suggest that, I suggest using a forged hook like everybody else.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[dhengr]

Kranmeste:
If the hooks were to be cast, they would be cast steel, not cast iron, an inferior material for this type of application. But, there are significant reasons why parts like hooks are usually forged as opposed to cast or made from plate. The forging prosses really improves and refines the grain structure of the material to conform with the shape of the finished piece, which is an improvement in something like a hook. It is stronger, less inclined to crack, etc. with the grain oriented properly to the shape and with respect to the predominant stresses and forces. Is casting really that much less expensive than forging, for 20 parts per year, when there are companies forging these kinds of parts on a regular basis?

 

[kranmeste]

Hi all,

thanks for your swift and very good replies.

I have become more convinced (searched google heavily today) that casted hooks cannot be used for reasons that you have all mentioned, and especially because of the porosity that will happen due to air cooling of the casted part.

I think that casted hooks can be used for tie down of parts, but not as a "below the hook" operation.

I will have to look into how much more expensive forging is with this relative low quantity.

Again thanks to all.

Regards
Jakob

 

[SnTMan]

I will have to look into how much more expensive forging is with this relative low quantity.

At a guess, one failed cast hook will pay for a large number of forged hooks.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand