Hook Latch Design per ASME B30.10

[OregonME85]

Looking into providing a carabiner style hook for dragline winching applications, wherein the hook latch could carry some of the load. This is similar to a carabiner, but with much higher loads. Could ASME B30.10 used for rating the hook with the latch open, or closed, or both?

Through reading the standard it states that the latch shall be designed to retain items under slack conditions, and it is not intended to support the load.​

Should the device be rated under ANSI Z359.12 and called a carabiner?

What are the thoughts out there?

Thanks!!

 

[dhengr]

OregonME85:
That piece of terminal hardware should probably be called a shackle or a hook with a latch on it. The latch on a hook is not intended to carry any load. It is intended to prevent the hook from becoming disengaged, even under slack conditions. I don’t think you want a carabiner, or anything like that for your loads. Look at some catalogs for wire rope and chain lifting terminal hardware. The Crosby Group, for example. The hardware comes rated by the manuf’er., and you know the cap’y. you need, its done.

 

[OregonME85]

Thanks dhengr for the input!

My company will be the manufacturer of the described hardware, I'm trying to determine what it should be classified as to determine the testing requirements. Whether it is a hook and tested to ASME B30.10 or a carabiner and tested to ANSI Z359.1

Think of something which could be similar to the below image.
If it were not for the locking and load bearing latch it would be called a hook.

 

[dhengr]

OregonME85:
I’d talk to the two ASME and ANSI committees and see which way they wanted you to go in designing, testing and rating something like this. They are the ones who have the final say, not some guys on an internet forum. Then, I’d make some, test them to failure and divide the min. breaking strength by 5 or 6, and call that the safe working load. Finally, I would drag a bunch of them through the mud, water, gravel, etc. in a mine or gravel pit for six months and see if your latch still worked. And, of course, since you insist that the latch should carry part of the load, the hook should certainly not be able to work, or to be used, unless the latch is fully engaged and locked. I would think that the latch you show is a little too fragile to be used in the construction or mining industries. That and its assured, consistent, operation would be the big design issues, since the latch is part of the load path. The fact is that you are kinda wanting to design a unsymmetrical link, where one leg caries 75% of the load and the other leg carries 25%.

 

[Sparweb]

What feature do you require that is not amply available from, say, the Crosby catalog?
What are you lifting/towing? What is being used now for the operation, and what is inadequate about that?

STF