winch equipment

[SnowRidge]

The OP wants to use parts and pieces without a high enough working load limit, apparently because he believes that it is safe to rerate them (he uses the term derate incorrectly) since they have a high overhead use safety factor.

Beyond the obvious question of how he knows the items in question have been approved for overhead lifting, it is never safe to try to outwit the design engineers and come up with your own ratings.

Tackle not designed for overhead lifting still has a large safety factor, if it is properly rated.

A 20,000 lb winch is huge. I assume he plans to mount it on something massive.

 

[Cord]

The winch is mounted to the rear of a small wheel loader. The safety fuse is a hydraulic relief valve.

 

[Shmudda]

I sure hope you people that think you can SAFELY use rigging equipment that is rated less then the winch can pull never design overhead cranes!

You have to remember something, if you have a large vehicle stuck in the mud up to the fenders how do you REALLY know how much tension you are applying with the winch? You can't really even tell how much tension is exerted if the winch stalls, because most winches are rated at their capacity with only 1 or 2 wraps of rope on the spool. So, if you are not spooled out the whole way then you are tugging at a somewhat less tension then full line pull.

I don't care what you say Cord, the Working Load Limit (WWL) is the Working Load Limit that the shackle can SAFELY lift, or pull. You NEVER take into account or use the safety factor to figure how much a piece of equipment can pull or lift. In essence, you never overload the rigging equipment where the safety factor is infringed upon and you always stay within the Working Load Limit of the equipment.

I'd like to hear some of you explain your line of thinking to OSHA........

Craig

 

[Cord]

Ok, let me explain this very clearly. The hook that came with my winch does not fit the clevis! The hook's throat opening isn't big enough to fit over the pin! The only way I can use this clevis is if I pass the hook through it and then hook the cable back on it's self. You guys are a calling this without having any idea of just how BIG a 12 ton clevis really is! The clevis's throat is big enough that my wrist will pass through it! A 2:1 safety factor is still twice what my winch is capable of! That is more than adequate for a non lifting application. With a 2:1 safety factor the clevis will never fail. The failure point will be my relief valve.

 

[Shmudda]

Cord,

I work in a Mill and can honestly say that a 12 ton clevis is one of the smaller units we use everyday, so I know the size well and also what I'm talking about here.

I understand your dilemma, do we use rigging that is always the same rating as the the crane, NO we don't. What you must understand from an industry, and SAFETY (OSHA) standpoint you are NEVER permitted to go into the safety factor of any lifting device.....period. The only time this is permitted is when you have an Engineered Lift with a crane and you can load it to 125%of the rated capacity MAX, even for an engineered lift. In doing that there are all kinds of redundant safety precautions that must be adhered to when doing something like this, but anything below the hook MUST be rated for the load being lifted. I know I am relating all this to cranes, lifting, and such, but honestly from a tension, or working load standpoint there is no difference between lifting and pulling, as 5 ton of tension is 5 ton, no matter if it's lifted or pulled.

Now to your winch issue.....

Would I use a smaller shackle, yes I would. Most likely you will never exert that much tension on the thing because most winches only work with the first 25 feet of rope, and the winch is pulling at far less then its rated line pull. When you are out and about playing in the mud, there are always trees within 25 feet of your vehicle. As for your winch hook, you can always replace it with something bigger, or just loop the end then you can use any shackle you want. Remember, never saddle a dead horse if you loop the end, meaning when installing cable clamps to create the loop, NEVER pinch the tension side of the line pull cable, always pinch the looped part of the cable with the u-bolt.

I take a very personal approach to lifting because just like bolts and fasteners it is the most LEAST understood part of basic mechanics and honestly if not done right mistakes can kill you or your buddy.

Take care and have fun tuggin!

Oh.......just one other thing.....

Cranes usually have a safety factor of 3:1
Lifting items (shackles, slings, chains) usually have a safety factor of 5:1, sometimes 8:1 if rated for severe duty.

Craig

 

[KHNewman]

Cord,

Are you sure that shackle is rated for overhead lifting? Generally chains and shackles certified for overhead lifting are Grade 80 or Grade 100. That shackle is Grade 43 and not rated for overhead lifting applications. Grade 80 and Grade 100 shackles and connectors are color coded. G80 is yellow or red and G100 is green or orange.

Take a look at this link...they sell a wide range of G43, G70, G80 and G100 chain and connectors. Chain Connectors | Truck n Tow.com

If I wanted a smaller shackle I would upgrade to G80 or G100 where you can get a higher WLL on a smaller diameter shackle. For example a G80 7/8" shackle is WLL for 19,000lbs and a G100 5/8" is rated for 22,600lbs vs. your G43 which is 1-1/4" and rated for 20,000lbs.

While a 12 Ton shackle should be fine on a 20K winch be careful how much you derate G43 because it does not have the safety factor built in that G80 or G100 have bulit in.

Also in winching applications shackles are not generally used to directly connect a hook or chain to the shackle. You would generally use a shackle that size to connect a heavy duty strap around an anchor point and then attach a snatch block to the shackle. You could also run a short length of have chain through the shackle and attach that to the winch. Make sure the chain exceeds the winch so the winch fails first. Why do you need to directly attach the winch hook to the shackle?

I can't agree more with everyone else here that you should never derate the WLL and that every connector or item attached to the winch line should meet or exceed the WLL of the winch. I had a 20K winch snap on me and I will tell you that it almost killed me. I was in the cab pulling a log onto the truck, I heard it snap and ducked across the seats. The line blew though the mesh behind the rear windshield, through the rear windshield and through the front windshield. If I hadn't ducked it would have cut my head off.

Be careful with that knid of power especially on a small loader where you have not protection. I would also suggest draping something heavy like a movers blanket over the winch line...it can save your life if you snap the line.

Kevin

 

[Bluehill]

I have a 20,000 lb winch I'm installing on a small loader. I wanted some rigging gear so I bought a couple of clevis's off Ebay. They were rated 12 tons. Looking at the clevis's, I now realize they were rated for lifting, not pulling. They way too large for my application. Anybody know how much a clevis would be derated for pulling?

Cord,

why don't you just put the clevis back on ebay and buy the appropriate size clevis for you needs. If the clevis you have doesn't work for you, buy another one, but make sure the WLL is 20,000 lbs or greater. Clevises designed for pulling are not really that expensive.

Trying to outsmart engineers who design this stuff for a living is a pretty silly.

rodger

 

[GE222]

Cord,
Listen to shmudda, as well as the other comments!

He brought up the same points I would have.

Items are de-rated for one reason - SAFETY!

Playing the game of figuring the breaking strength versus load rating is a dangerous game. Eventually it will get you into trouble.

I would not want to be around when a winch rated at 20K was pulling close to its rated load and the cable broke loose!

 

[Renze]

At work we service the 15 ton wheel loaders for the army. They have a winch on the front frame between the lift arms, rated at 15 ton. When the bucket is placed in the dirt, with a snatch block on top of the bucket, the winch will pull all four wheels of the loader in the air. so it does a wee bit more than 15 ton: The army often doesnt even call in their recovery tanks, but pulls just anything with the loader which is at every camp anyways.

 

[Renze]

Trying to outsmart engineers who design this stuff for a living is a pretty silly.

Thats exactly what competitor B is doing to stay competitive... And C.. and D...


Anyways, when installed on the back of a `small` loader, the winch strength is certainly not going to be the factor that decides the max line pull: He'll just move the loader, or pull the bucket dump cylinder through its relief valve.



The reason for the higher safety factors for lifting chains, is that you often put two cables on one object to form a triangle: this will increase the tension in the lifting chains quite a bit. With simple straight recovery winching you dont have this effect so personally i dont worry about using a 10 ton lifting chain with factor 5, for a 16.66 ton recovery winch so in this application you end up with factor 3