A-572 steel VS T-1 steel

[stevenf]

I posted a question on attachments essentially asking which is the better steel to use for a grapple bucket and got no responses as of yet. I've really got to have a decision on this tonight so that when I go meet with the dealer in the AM I know what to tell him to do. He ordered a FCC grapple and FCC blew it and welded up for the wrong loader and it has to be shipped back to fix 2 weeks to fix and ship both ways. Hardened Pins look wrong and the cushioned cylinders may not be on it either all of which I've paid for or am getting ready to. Please respond as I don't have a clue as to if the competitors are using equal materials although theirs are ready to ship I don't want to wish after bending up a 4,000.00 grapple that I had waited for FCC to fix this mess. PS they also in the process of trying to get the current grapple to fit, ground off the bottom braces on the new Kubota Quik-tach at FCC's insistence which they are paying to replace after they realized they made the bucket for the wrong loader 1250 instead of 1251.

 

[markct]

im not sure i understand what you are doing here, is the dealer making a brand new grapple for you? or just modifying the one that they sent that wasnt right? as for the question about what steel is better i am not ceartain but i believe t-1 is more ductile than a-572 is, thats what i know the welder in a shop i have worked at always said, he didnt like a-572 at all, only wanted t-1 plate, but thats the only info i have, if ya could say what it is your trying to actualy do it may help

 

[RICHARDG]

steve,,maybe help a little,,first,,there are four grades of a-572,,all are considered a high strength,low alloy steel,the first two slightly better than plain old a-36,as far as yield and tensile,,the next two,grades 60 and 65,,are a lot stronger than a-36,,,,there are at least three grades of t-1, which is considered a quenched and tempered high strength steel.all are very high tensile,and would probably just be used on edges rather that the whole bucket of something,,,??The main thing is,,since you refered to 572,,,than that must be what you think its made of,,,,which,in this situation,would be a better grade of steel than a-36,,,which is good thing,,,,don't know about different brands etc,[of one being better than other],,,main thing is warrenty if you are really worried about something working out,,,but all steel either bends or breaks at some point in a tensile/bend type test,,,sometimes its a good thing for it to bend instead of break...thingy

 

[RICHARDG]

Mark,,if your talking about the same t-1 steel,,I am,,,you may have that backwards,,,all the t-1's I can find are over 100,000 tensile strength,,,the 572 highest tensile[grade65],is 80,000,,,a-572 is used in many places,[welded],,,don't think I have ever been involved with welding t-1,,,,,now there is a term called,P-1,steel,,,,thats a group of steels,plain ole a-36 being among them,,,Not sure what P group 572 falls into,maybe P-3,you would need to use a different filler metal on them also,maybe an 80,000 tensile with some alloy additives[8018-B ,thingy

 

[markct]

yea that may be right, i just remember him argueing with the shop foreman cause they had ordered a different steel than the welder wanted and he was sayin it was gona crack and all this stuff, it may well have been opposite of how i remembered it.

 

[Villengineer]

I design equipment using all 3 of the basic alloys you have listed: A-36, A-572, and T-1. It is correct that there are different grades of each. All three are weldable, however if done correctly T-1 requires a more involved process. We weld A-36 and A-572 gr50 interchangably. There is enough difference between common A-36 (it is also available in higher grades) and A-572 to warrant differentiation. I would guess that if they list A-572 that they mean gr50 as I believe that it is far more common.
I won't bore you with all kinds of engineering mumbo-jumbo but for this application for a diven part the biggest advantage that T-1 has over the other 2 is it is a better wear surface. Whether you need that or not would depend on your specific application.