Malleable vs Forged Wire Rope Clips

[Lambda]

Well, I know that forged crosbys are where it's at for rigging, and that malleable wire rope clips shouldn't be used. But what I never learned was what's the real difference? What makes the forged ones stronger? And why are they called "malleable"? They don't appear to deform when tightened, and I can't crush them with a channel-lock pliers. I got to thinking about this, when I realized that pretty much all of the crosbys we have are the malleable ones. As part of my plans to get rid of unsafe stuff, I've just ordered a boatload of forged ones.
Also, if not for rigging, what ARE malleable crosbys good for?

 

[mstaylor]

Malleable metal is cast metal and tends to be brittle. Take a plumbing elbow and hit it with a hammer, it will break easily. Forged metal is shaped by hammering or in this case, bend by hydralics. It is a much stronger product that will not break under load. Malleable crosbys should be used in light situations that don't require rated gear. Forged Crosbys should be used in heavier loads that are be in conjunction with rated equipment.

 

[FatherMurphy]

The main difference between forged and cast (regardless of alloy being used) is that a forging starts as a solid piece of metal, but a casting is metal that is melted and poured into a mold. During the casting process, voids can form by either early cooling or some of the pattern sand coming loose and ending up inside the casting. These voids greatly weaken the resulting part, and can't always be detected from exterior inspection.

Forgings are solid chunks of metal heated until soft, and then pressure formed into the desired shape. There is no chance of a void forming, thus a more reliably strong part is the result.

Usually, a faulty cast cable clip will fail during installation, but riggers tend to be allergic to phrases like 'usually' and 'most often', given that the result of a failure after installation can so easily result in damage and injury, thus the very strong preference for forged clips.

 

[MPowers]

FatherMurphy said it pretty well. One point here.... if they're malleable, they're NOT Crosbys. If they're Crosbys, they're NOT malleable. Just a point of semantics.

 

[mstaylor]

The main difference between forged and cast (regardless of alloy being used) is that a forging starts as a solid piece of metal, but a casting is metal that is melted and poured into a mold. During the casting process, voids can form by either early cooling or some of the pattern sand coming loose and ending up inside the casting. These voids greatly weaken the resulting part, and can't always be detected from exterior inspection.

Forgings are solid chunks of metal heated until soft, and then pressure formed into the desired shape. There is no chance of a void forming, thus a more reliably strong part is the result.

Usually, a faulty cast cable clip will fail during installation, but riggers tend to be allergic to phrases like 'usually' and 'most often', given that the result of a failure after installation can so easily result in damage and injury, thus the very strong preference for forged clips.

Things you never want your rigger to say is it should be ok, or usually it isn't a problem. There is a reason there is a T shirt that says,"If you don't at first succeed then rigging isn't for you." And MPowers is correct, they aren't crosbys but many use it as a generic term.