Miller Electric

Welding Discussion Forums

Home » Resources » Communities » Welding Discussion Forums

The forum is currently undergoing maintenance and is in a 'read-only' mode for the time being. Sorry for the inconvenience.


  • If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Announcement

Announcement Module
Collapse
No announcement yet.

Welding AR 400 Plate

Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts

  • Welding AR 400 Plate

    Does anyone have experience welding AR400 plate ?

    I have a job comming next week, I'll be welding a 4'x 6' AR 400 plate inside of a Large vat for mixing types of soil & fertlizer

    I haven't seen it yet , but from what they say it's quite a large Vat .

    So any insight from anyone that's done this before would be great !
    It's being Rolled this week , to be installed next week .

    .......... Norm

  • #2
    Norm right from Lincoln.

    AR400 is a quench and tempered steel and may be difficult to weld due its high strength and hardenability. The base steel around the weld rapidly heats and cools during welding, resulting in a heat affected zone (HAZ) with high hardness. Any hydrogen in the weld metal may diffuse into HAZ and may cause hydrogen embrittlement, resulting in delayed underbead or toe cracks outside of the weld. To minimize heat affected zone cracking:
    Use a low hydrogen consumable with an -H4 or -H2 designation.
    Preheat to slow the cooling rate. Note that excessive preheat may anneal the base material.
    Slow cool. More time at elevated temperatures allows the dissolved hydrogen to escape.
    Peen the weld beads to minimize residual weld stresses.
    Use the lowest strength filler metal meeting design requirements. If making fillet welds, the weld can be oversized to give the specified strength
    Minimize weld restraint.

    Comment


    • #3
      AR 400 plate.

      Originally posted by Sonora Iron View Post
      Norm right from Lincoln.

      AR400 is a quench and tempered steel and may be difficult to weld due its high strength and hardenability. The base steel around the weld rapidly heats and cools during welding, resulting in a heat affected zone (HAZ) with high hardness. Any hydrogen in the weld metal may diffuse into HAZ and may cause hydrogen embrittlement, resulting in delayed underbead or toe cracks outside of the weld. To minimize heat affected zone cracking:
      Use a low hydrogen consumable with an -H4 or -H2 designation.
      Preheat to slow the cooling rate. Note that excessive preheat may anneal the base material.
      Slow cool. More time at elevated temperatures allows the dissolved hydrogen to escape.
      Peen the weld beads to minimize residual weld stresses.
      Use the lowest strength filler metal meeting design requirements. If making fillet welds, the weld can be oversized to give the specified strength
      Minimize weld restraint.
      Thanks Sonora;
      I was somewhat framiliar with what you stated above.
      So E- 7018- H4 would be the best rod to use, with mild pre-heat.

      I'm not sure how I could slow the cool down time?
      Peening , Yes !
      It's a fairly large piece of plate- 4'x6' rolled , I'm not sure of it's thickness.
      Do you think I should back - step my way around the perimiter ?

      .............. Norm

      Comment


      • #4
        I back step everything!!!!!!!!!!!!!!!!!!!!!!!!!!
        Maybe rent one of these for the post heat?


        http://www.masterheaters.com/kero/

        Comment


        • #5
          AR 400 plate .

          Sonora, No I don't think I'll use one of those heaters !

          It's a very confined space !
          I'll be inside a Vat welding a 4' x 6' plate , Hot and Smokey enough !!!!!!!!!!

          ............ Norm

          Comment


          • #6
            I remember welding it down in conveyors, mild pre-heat and lo-hi. I dont think its a big deal.

            Comment


            • #7
              Originally posted by nfinch86 View Post
              Sonora, No I don't think I'll use one of those heaters !

              It's a very confined space !
              I'll be inside a Vat welding a 4' x 6' plate , Hot and Smokey enough !!!!!!!!!!

              ............ Norm
              LOL!
              No I meant after you’re completely done. Aim the heather inside the vat, and let it cool with just this amount of heat.

              Comment


              • #8
                Originally posted by Sberry View Post
                I remember welding it down in conveyors, mild pre-heat and lo-hi. I dont think its a big deal.
                That is all I ever done too. I was a little set back by how detailed Lincoln made it out to be. Guess I was lucky all those years!

                Comment


                • #9
                  Nabed this from the hobartwelders

                  http://www.hobartwelders.com/weldtal...ad.php?t=19493

                  Comment


                  • #10
                    AR 400 Plate

                    Thanks, Fab Tech, Sonora & everyone else !!!!!!!!!

                    I do have one of those propane heaters, but the darn thing will lite but Not stay lit .

                    So I guess it will be E-7018- H4 or H2 , with mild pre- heat, back stepping around the perimeter, peening as I go !
                    It's an inside job, so it should not cool too quickly, maybe cover it with a weld blanket .

                    ............ Norm

                    Comment


                    • #11
                      Be safe in the Vat

                      Originally posted by nfinch86 View Post
                      It's a very confined space !
                      I'll be inside a Vat welding a 4' x 6' plate , Hot and Smokey enough !!!!!!!!!!

                      ............ Norm
                      Hey Norm, you be safe in that Vat, remember all your safety in there.

                      I thought there was a post some time ago that mentioned someone used sand to cover their finished welds to slow the cooling. If I remember right you could do that to slow the cooling.

                      Comment


                      • #12
                        Used Lincoln Ultracore 71A85, 1/16 for all of the AR400 we welded when I worked for a John Deere construction equipment dealer. Never preheated, we always cut and burned!! Never had any problems with it.

                        Comment


                        • #13
                          No biggie...

                          Weld Ar400, 450 all the time use either 7018, or Outershield 71. If it is under 1/2 plate, I have never had to preheat. Will worn you to be careful at the end welds. I like to run the weld past the plate, As 450 plates likes to crack at the ends of the welds. Also enjoy beveling it if you have to, use an Air Arc as grinding it is difficult.
                          Kevin

                          Comment


                          • #14
                            AR 400 Plate

                            Originally posted by TerryL View Post
                            Hey Norm, you be safe in that Vat, remember all your safety in there.

                            I thought there was a post some time ago that mentioned someone used sand to cover their finished welds to slow the cooling. If I remember right you could do that to slow the cooling.
                            Thanks Terry;

                            Will Do !!!!
                            Ya, As far as I know it's a Mixing Vat, so I'll have to make sure to Lock it out !
                            I guess it's like a Giant Kitchen Mixing Blender !
                            Big, Big motor , it would make short work out of a person caught in there !

                            ............ Norm

                            Comment


                            • #15
                              AR 400 Plate

                              Originally posted by Tryagn5 View Post
                              Weld Ar400, 450 all the time use either 7018, or Outershield 71. If it is under 1/2 plate, I have never had to preheat. Will worn you to be careful at the end welds. I like to run the weld past the plate, As 450 plates likes to crack at the ends of the welds. Also enjoy beveling it if you have to, use an Air Arc as grinding it is difficult.
                              Kevin
                              Tryagn5, Thanks,..... I'll be using E-7018 H4 & I'll definitly keep in mind about the cracking at the ends. I'll run past 1/2" or so on each end !

                              Thanks Man !

                              ............. Norm

                              Comment

                              Working...
                              X
                              Special Offers: See the latest Miller deals and promotions.