For liability reasons, I would contact the manufacture and ask for a welding procedure that pertains to the part of the boom you are going to fix. We do many repairs/ modifications/ upgrades to crane booms and other lifting equipment. Most manufactures understand that over time things need to be repaired, and they have all of the proper procedures to ensure nobody gets hurt from a repaired piece of equipment. This will cover your liability and ensure the proper fix was put in place.

MDG is giving you the correct advice. You really do need to get the repair procedure from the manufacturer. I don't think you want the liability of an incorrectly repaired boom, nor want to learn the boom failed and hurt or killed anyone.

We do boom repairs on our own equipment and based on that experience, I can tell you that the filler metals you have listed are not what needs to be used. The manufacturer knows exactly what the booms are made of, how to repair them, and what testing needs to be done.

Chet

Good advice from everyone. Always go to the manufacturer to see what they recommend. However, an additional piece of advice; if you use SMAW electrode, it will be a low hydrogen type. Make sure you use electrode that has been stored properly. By that I mean, make sure the electrodes are stored in an electric electrode holding oven and "always" stored at 250 degrees F (or higher) once they are removed from the hermetically sealed container they were packaged in by the manufacturer. Many welders do not understand that the flux will absorb moisture. If the electrode oven is turned off over night or over the weekend, they will absorb moisture from the environment. Simply heating them to 250 degrees for a couple of hours will not "drive" the moisture out of the flux. The moisture can combine chemically with the flux. Some high strength electrodes (11018 as an example) may function best if they are baked at a high temperature before use.

Even the flux cored electrode should meet the low hydrogen requirements. The flux cored electrode can be purchased in sealed cans if you order it as such.

Good luck - Al

Hello cuco, some may agree and some may disagree, I have one other suggestion for you to consider. Caterpillar, as many are aware has been in the heavy equipment game for a considerable number of years, thus they have done extensive research and engineering considering boom design and other types of industrial applications. They have a publication that deals specifically with boom repairs and other types of related repairs, you may want to see about gaining access to this information for procedures, ideas, suggestions, adaptability, etc. I am not suggesting that you ignore liability issues or the other suggestions that the other posters have made. What I am saying is that some manufacturers will want to sell you a new boom as opposed to giving you valid suggestions and information for repairing the one that you have. So if you find that this is the case the Cat information will be an invaluable resource to draw from. One small footnote for the masses, I worked on the main boom off of a 245 Cat trackhoe a number of years ago, my employer was also concerned that we should use the correct filler metals to make the repairs so he cut out some of the material and sent it off to the lab for identification, it came back as A-36 mild steel, we were expecting an alloy of some sort, go figure. My 2 cents. Regards, aevald