Understanding the Difference between Chain Grades and How They’re Used

36 comments

by  on May 7, 2015

chain grades
Chain has been around for over a thousand years. It is one of the most versatile and reliable ways to lift, tension and tie down materials in a variety of applications. In the past, people would use any type of chain to lift something, tie down a load or tow a vehicle. Proper inspection, safety procedures and general standards of practice for chain were lacking.

In recent years, due to safety concerns and regulations, the industry has begun to differentiate between various materials and grades of chain and the specific applications they should be used for. ASTM (American Society of Testing & Materials), ASME (American Society of Mechanical Engineers) and OSHA (Occupational Safety & Health Administration) began to publish safety standards and regulations for the manufacturing, testing, use, inspection and repair of chain.

Chain Grades

One of the safety measures implemented was to place chain in Grades based on the ultimate breaking strength of that chain. This number is what we see today G30, G43, G70, G80 & G100 and the common chain grades. The number after each letter is N/mm2. For example, G80 means that the maximum stress on the chain at ultimate strength is 800 newtons per millimeter squared.

Working Load Limit (WLL) of Chain

The other safety measure was identifying which types of chain are appropriate and strong enough for overhead lifting. Anytime we move or lift a load it is dangerous. Moving a load along the ground has the advantage that the ground is supporting the load. We have to overcome the coefficient of friction to move the load. The chain’s working load limit does not have to match the weight of the load. It needs to be able to handle the tension applied, which is based on the surface that it is being moved over plus some fraction of the weight of the load. This can be calculated using formulas.

If we lift that same load off the ground, we now have to overcome gravity. The chain’s working load limit will have to be of sufficient strength to support the weight of the load plus any additional forces imposed by angles and hitch type(s) used.

Which Chain Grade Should Be Used for Which Type of Application?

Alloy Chain Grade 80 or Grade 100 should be used for overhead lifting. ASTM states that alloy chain shall be able to elongate a minimum of 20% before fracture (7.3.5). To ensure that alloy chain consistently meets this requirement, ASTM requires the use of certain alloying elements in the manufacturing of the steel for alloy steel chain. These alloys can vary from company to company, but some key requirements are specified by ASTM. The alloy properties also improve the wear and tear that the chain will experience.  Note that when chain is in use, no amount of stretch is allowed.

Carbon Grade 70 chain is a “heat treated” carbon steel chain that has no alloying elements added to the steel. This chain will elongate before breaking but does not have the properties needed for overhead lifting; therefore, Grade 70 chain is not intended for overhead lifting. This chain is designed for use as a tie down chain or lashing for transportation. Grade 70 chain has a gold chromate finish to help resist corrosion from continuous exposure to the elements and the rigors of highway use, such as road salts in the winter.

When any type of overhead lifting is required, use only alloy chain slings unless specified by the manufacturer.

The preferred chain for load securement is Grade 70, but any grade of chain can be used for tie downs or tensioning. You have to know your tensions in order to select the proper chain. Refer to load securement safety standards FMCSA (Federal Motor Carrier Safety Administration), CVSA (Commercial Vehicle Safety Alliance), WSTDA (Web Sling Tie down Association) or the state regulations for more information.

Training is key in knowing how to properly size and use any type of chain for any application. Learn more about Columbus McKinnon training programs.

Watch our Safety Webinar on Load Securement.

{ 35 comments… read them below or add one }

Henry Brozyna Henry Brozyna February 22, 2017 at 12:12 pm

Hi William,
Manufacturers typically do not publish the hardness of the Grade 100 chain. In ASTM A973, the Grade 100 Chain specification does not specify a hardness. This standard is built around ensuring the strength and ductility of the product. The standard states that the chain shall be quenched and tempered. The hardness is dependent upon several factors ranging from material diameter to chemical composition of the steel used for manufacturing. Therefore, the actual hardness of a particular chain may vary slightly from lot to lot and manufacturer to manufacturer.

Thank you for reaching out to us.
Rodney Reynolds, General Manager – Lexington, Tennessee Operations & Henry Brozyna

William Siegal February 20, 2017 at 9:49 pm

Hello Henry,
Is there anywhere that I can locate the Brinnell/Rockwell hardness values for the various grades of chain? I am looking to purchase a heavy duty bolt cutter to chop my chain into one or two foot lengths for use in the set-up of rock climbing rappelling stations, and I need to purchase a cutter with blades of the appropriate hardness. For instance, the best cutter that I could locate claims to be capable of cutting metal with a Brinnell 450/ Rockwell 48 hardness value. Would this handle grade 43, 70, 80 and 100 chain? Thanks for any light that you can shed on this subject.

JAYA January 18, 2017 at 6:17 am

Thanks ,you explained very well.

Henry Brozyna Henry Brozyna January 17, 2017 at 8:41 am

Hello Nail,

I would suggest contacting the manufacturer for the machine, Peterson This is their phone number: Peterson Call Center (888.813.0712). Also their website http://www.petersoncorp.com/ They may have a special chain they use that I am not aware of.

Thank you,
Henry

NAIL January 17, 2017 at 4:49 am

Hi Mr. Brozyna ,
We have in our factory one Delimber Debaker Peterson Model DD 4800 .
This machine have two drums . Every drum have 6 shafts . On everyone shaft are
13 section of 5/8″ chain . Every section have 8 links . Please can you tell me which grade must have this chains . For one change we use 156 sections ( 8 links )

Best regards
Nail Nadarević dipl.ing.
Moderator d.o.o.

Henry Brozyna Henry Brozyna January 11, 2017 at 3:37 pm

Hi Mark,
We understand what you are speaking about regarding synthetics. However, the intention of this article was to educate about chain and how it is used. That is why we never spoke of synthetics.
Thanks,
Henry

Henry Brozyna Henry Brozyna January 11, 2017 at 3:03 pm

Hi Robbie,

Below is a section from the ASME B30.16 standard that outlines hoist chain inspection:

16-2.1.1 Inspection Classification
8) load chain for gross damage, which may be an immediate hazard, such as the following:
(a) Examine visually for gouges, nicks, weld spatter, corrosion, and distorted links.
(b) Test the hoist under load in lifting and lowering directions and observe the operation of the chain
and sprockets. The chain should feed smoothly into and away from the sprockets.”

You should also find out what the manufacturer of the hoist you are inspecting has said about hoist chain inspection.
The manufacturer criteria may be different than the standard and more focused on a particular product.

As for the Grade 80 & 100 chain you mentioned, Grade 80 & 100 are sling chain and should not be used in a hoist.
These are alloy chains, made per the ASME B30.9 standard which states that the alloy chain must have the ability to elongate 20% before ultimate failure.

If we had a piece of say, Grade 80 or 100 chain, in a hoist, and it began to elongate, the chain would not fit the pocket wheel geometry and the possibility of failure would increase.

Manufacturer supplied hoist chain does not have the ability to elongate that much (20%) so that the geometry of the chain matches the geometry of the pocket wheel.

So,if sling chain is being used in a hoist, I would recommend that the hoist be removed from service and the chain be replaced with the proper chain. The hoist should also receive a 100% inspection.

Thanks for your question.
Henry

Robbie Elford January 10, 2017 at 5:15 pm

Good Afternoon, Henry!
What are the current specifications for hoist chain, grades 80 and 100, for maximum reduction in cross section in both powered and manual hoists.
Looking forward to hearing from you.

mark January 10, 2017 at 4:01 pm

I am a bit surprised that no mention of synthetic polymer ropes have been made.
I realize they do have their limitations but the damn stuff has some very impressive properties of which the most impressive one is weight. Amsteel Blue has the same strength as equal diameter of wire rope and the stuff floats. I bought a 120′ by 1 1/8 piece of Amsteel II plus with eyes on Ebay for 2.50$ a foot that weighs 45 Lbs. It has an average breaking strength of 90,000 lbs and a certified safe wll of 15,ooo lbs. A grade 100 chain with same specs is 7$/ft plus shipping and weighs 330 lbs. The stuff (which is made of “Dyneema” fiber is all over ebay with dozens of manufacturers and with really good prices if you do your homework and look hard enough. Just something to think about…..

Henry Brozyna Henry Brozyna January 9, 2017 at 8:09 am

Hello Ahmad,
Grade 80 & 100 chain is what you want to use for overhead lifting. The reason is, per ASME B30.9, the chain must be able to elongate at least 20% before ultimate failure.
The markings on those chains are required also per ASME B30.9. If those markings are not legible, the chain must be removed from service, not de-rated.
As for any other means of identifying the chain as grade 80 or 100, no.
The only means we have is the tag that is on the chain and the markings on the chain itself.
If those are gone or not legible, the sling must be removed.

Thanks for your question.
Henry

Ahmad January 4, 2017 at 10:08 am

Hi Henry,

For overhead cranes , chain slings with grade 80 or 100 is only allowable, and if it is not legible on the chain components then the inspector should consider it grade 30 and no other evidence available to communicate its grade, it should be disposed off in that case or not?
And if it is not, is there any techniques to proof its grade rather than contacting the manufacturer because no data available for this chain sling.

swlifting January 4, 2017 at 1:22 am

Hi Henry Brozyna,

Thank you very much for sharing the valuable information. And what about the Grade 120 chains? where it can be used? can you please give some additional information about the grade 120 chains.

Well appreciated.

Henry Brozyna Henry Brozyna December 2, 2016 at 5:22 pm

Hi Rowdy,
That would depend on the size of the chain & the manufacturer.
Each manufacturer has a capacity list that can be referenced.
Please visit our two sites that I’ve listed below for more information:
http://cmworks.com/Rigging/TransportChainAttachments
http://cmworks.com/Rigging/TransportChainAttachments/Assemblies/CMWeldedAssembly/Grade70

Henry

Rowdy December 1, 2016 at 1:14 am

How many pounds are the gold tow chains rated for?

Troy Raines Troy Raines November 17, 2016 at 8:47 pm

Hi David,
Thanks for writing us! G43 and grades of chain made for lifting (G80 and G100) are such similar materials there is no relevant difference in their corrosion rates when used with stainless steels.
Troy

David November 15, 2016 at 3:57 pm

Hello! I am a rock climber and utilize 3/8″ chain for anchoring systems to decrease the load angle on the anchor bolts. As a general rule we stay away from plated steel because of the tendency to create a battery affect when combined with our SS hardware in the rock.
All of the hardware I use is stainless steel (except for the G43). However, since I am using A LOT of chain, it seems much more economically feasible to not purchase SS chain. I like the G43 self-colored for its WLL, wear longevity, and comparably low corrosive properties. My question is this. I read, (somewhere I have not been able to find again), that G43 has a lower corrosion rate with SS than other steel grades. Is this true and where the heck can I find it?

Tommy October 1, 2016 at 2:32 pm

Hello Mr. Brozyna,

Can I use lifting chain as a security chain for locking and securing my bike? I am looking at Grade 100 in the form of a 16mm diameter chain.

Thank you.

Regards,
Tommy

Henry Brozyna Henry Brozyna September 19, 2016 at 6:35 pm

Hello Wences,
Grade 7 is not the same as Grade 30
G30 has a lower WLL than G70 of the same size chain.
G30 is a general purpose use chain and can be found in most hardware stores.
G70 is primarily used for load securement.
Just a note in closing, neither of these chains can be used for overhead lifting.

Thanks,
Henry

Wences Baez September 19, 2016 at 10:31 am

Hi Henry,

Is it Grade 7 same as Grade 30 in Chain Classifications?

Thank you

Wences

Henry Brozyna Henry Brozyna August 24, 2016 at 9:48 am

Hi Sean,

I would suggest that you find a distributor of CM hoists in your area.
Once you do that, I would also recommend doing a complete inspection of the hoist to make sure everything is working correctly and to make sure that no parts are worn out.
Once you have done that, that same distributor should be able to supply you with the longer chain for that hoist.

Henry

Sean August 19, 2016 at 10:36 pm

Hello,

I have a 2 ton hoist I bought that I will use periodically to lift things into my loft and occasionally to pull a motor or even conceivably lift a front end if need be. It came with a 10 foot chain and I would like to replace the chain with a longer chain but do not know what kind I need to look for. What advice do you have in that regard?

Henry Brozyna Henry Brozyna August 5, 2016 at 3:51 pm

Hi Ron,

First, G43 has a WLL of 5400 lbs and is self-colored, no plating.
G70 has a WLL of 4700 lbs and has a gold chromate finish, less chance of rust.
Since you are living in western NY and you are planning to use this chain for pulling in wet conditions, I would recommend the G70.

Thanks for reaching out to us!
Henry

Ron T. July 29, 2016 at 1:50 am

Hey Henry,
Thanks for taking the time to educate us. I think my question is pretty simple, and hopefully easy for you to answer.

I am interested in purchasing a chain for various chores; pulling bushes/tree stump and the occasional vehicle recovery from the snow (I live in Western NY and feel bad when I pass by someone stuck in a snow bank).

I have the option to purchase either of the following 2 chains;
1. 3/8″ x 14′ Grade 43
2. 5/16″ x 20′ Grade 70
3. Your suggestion that would best suit my needs.

Thank you in advance for your time and reccomendation Henry.
Ron

Henry Brozyna Henry Brozyna July 6, 2016 at 9:11 am

Hello George,
Per ASME, Grade 43 chain is also known as high test chain & has no alloy properties.
I have not heard of grade 40 chain so I cannot comment on that one.
Please remember that this blog post is in regards to the ASME standards as they apply to North America.
Thanks for writing us.
Henry

George Mclean July 3, 2016 at 5:11 am

good day henry, i am currently studying for LEEA exams ( they LEEA refer to grade 40 chain ) in some questions where above refers to grade 43 Alloy chain, my question is is there a grade 40 ? or does the word grade cover several type of chain. much appriciate any clarification.

regards
george

Henry Brozyna Henry Brozyna June 10, 2016 at 5:31 pm

Hello Jubair,
Thank you for your question. Sling chain & hoist chain are made differently.
Sling chain, G80 or G100, according to ASME B30.9 must have the ability to elongate a min. of 20% before complete failure.
It is more ductile than hoist chain for that reason.
Also sling chain is designed to go around the load & come in direct contact with the load, hoist chain is not to contact the load.
Hoist chain, because it has to go around a lift wheel that has the same outside shape as the chain, it cannot have as great an elongation as sling chain. Simply put, it wouldn’t fit the lift wheel.
So do not use sling chain, G80 or G100, in your hoist. It is very dangerous.

Henry

jubair May 26, 2016 at 3:43 am

Hi,

Can you please advise why the chain used for chain sling is more ductile than the chain for chain hoists?
Why can’t we use the sling chains for chain hoist load chain?

Thanks

Henry Brozyna Henry Brozyna May 16, 2016 at 8:33 am

Hi Lindsay,
That is going to vary by manufacturer.
Some will use G80, Grade80, HA800 or G8.
It will be the same variation for the other grades of chain.
The number, for example, 80. You should see the number 8, 80 or 800 after some kind of a letter(s) designation.
This is something all chain manufacturers are doing to remain consistent throughout the industry.

Henry

lindsay May 16, 2016 at 3:35 am

can you tell me the letter used for
grade 80 chain
grade 50 chain
grade 30 chain

thank you

Henry Brozyna Henry Brozyna May 13, 2016 at 1:41 pm

Hi Chaz,
Are you talking about wear or stretch?
If it is wear then we are allowed 10% or whatever the manufacturer recommends.
If it is stretch then no stretch is allowed.
I hope this helps.
Henry

Chaz May 12, 2016 at 10:51 pm

Hello Henry,

I am currently studying for a test and a the following question was asked. If you have a 20′ chain what can is the maximum it can stretch before you must dispose of it. the first logical answer that came to mind was, that if it stretched at all then it I would personally dispose of it. however, that was not one of the multiple choice options. they were:
20’6″
21′
22′
23′

I am totally lost on this one. I checked the IBC and other reference material and have not had any luck. any help you provide would be greatly appreciated.

Respectfully,
Chaz

Henry Brozyna Henry Brozyna May 5, 2016 at 11:39 am

Hi Rikki,
The grades of chain referred to in this blog are based on ASME B30 standards.
ASME standards are applicable to North America. The UK & Europe have EN standards.
Henry

Rikki May 5, 2016 at 11:01 am

Hi,

Are these chain grades the same ones in use in the United Kingdom?

Henry Brozyna Henry Brozyna April 27, 2016 at 8:23 am

Hi Shaun,
G80 chain can be used to lift loads, but is not to be used in a hoist.
Hoist chain has different properties than G80 chain.
Per ASME B30.9 sling chain, G80, must elongate at least 20% before breaking. If this chain were used in a hoist and it started to elongate, say 5%, it would no longer be able to go over the pocket wheel. With any amount of elongation, the chain must be removed from service.
So, G80 as a sling for lifting is ok. G80 as a replacement for hoist chain is not acceptable.
Henry

shaun April 26, 2016 at 9:05 pm

can the G8O chain be used in chain Hoist or would it carry a different mark?

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