Pre qualified procedure

Date 04-22-2004 19:45

There could be couple of problems with the procedure if you are intending to use a prequalified one Per AWS D1.1. First, there are no prequalified procedures for downhill welding with the exception of fixing undercut, and tubular products (See paragraph 3.7.1- 2004 edition), and secondly, 3.13.3 (2) says that there are no prequalified CJP groove welds in butt joints made from one side witout backing, along with the fact that there are no CJP prequalified groove details. If you are using PJP, then it could be acceptable.

By swnorris (****)

Date 04-22-2004 21:04

I see you work for ESAB. I am in the process of switching from Lincoln 71 Elite .045 diameter to ESAB Dualshield 7100 .045 diameter because of the price difference. The only thing about the ESAB wire that the guys dislike is that they can't bend the wire and break it off like they could the Lincoln wire. Why is that? Anyway, downhand welding is defined in Jefferson's Welding Enclycopedia as flat position welding, in which the weld is made in a workpiece in a horizontal plane. Since you also said "welding down", I guess you are referring to vertical down. If so, AWS D1.1 addresses vertical down in paragraph 3.7.1 under General WPS Requirements, which in essence says that when tubular products are welded, the progression of vertical welding may be upwards or downwards, but only in the direction for which a welder is qualified. It also says that undercut (interpreting this to mean tubular and nontubular) may be repaired with vertical down, as long as the preheat conforms with Table 3.2, but not lower than 70 degrees F. To my knowledge, if you're welding to D1.1, there is not a prequalified procedure for vertical down welds. Also, you shouldn't have a problem welding vertical up with 7018 low hydrogen rods.

By ladycwi (*)

Date 04-22-2004 22:58

No, no problems with the Vertical up position with the 7018, but some people were speaking of procedures for welding Vertical Down, open root with no backing, back gouge and replace with a backing weld. I know that in D1.1 it allows downhand welding for repairs of undercut, the only time I have ever heard of Vertical Down Welding is that of welders on gas lines and tankies. It sounds to me like it can be done if the procedure is qualified. Correct? Also, the reason the wire may not be able to break so easily may be because of the chemistry of the steel used to make the wire, will let you know more in the a.m., by the way that is a very good wire, I enjoy using it.

By jwright650 (*****)

Date 04-23-2004 09:58

Hi swnoris,
We use the ESAB wire 3/32(E70T-1 Dual shield 111-AC) and 1/16 (Dual shield ARC 71) , and our guys still bend the wire back and forth to break it off. I personally like the use of side cutters. Watch those guys that like to bend the wire back and forth, they'll arc it off on the table to trim it also. I have torn more than one pair of jeans stepping over the horse(table) and hanging my pants on some of that wire.
John Wright

By ladycwi (*)

Date 04-23-2004 11:19

I was right about the wire, the chemistry of the band we use is most likely different than Lincolns Wire.

By swnorris (****)

Date 04-23-2004 14:30

I have the twelfth edition of The Procedure Handbook of Arc Welding from 1973, which was published by Lincoln. I don't know how much the technology or techniques for vertical down have changed over the last 30 years, because we don't do vertical down, except as permitted in D1.1. There were no procedures written in the Lincoln book for vertical down welding in the SMAW process, except for a few using E6010, 6011, 6012, and 6013 electrodes, and those were for a plate thickness range of 18-10 gage. Out of morbid curiosity, I checked the other welding processes in the book and found only one more procedure for vertical down, which was in the FCAW process using E70T-G on plate in the thickness range of 12 gage -1/4". I also looked through my “welding stuff” file and did manage to find the following information about vertical down that may be helpful: Vertical down welding is better suited for welding light gauge metal because the penetration is shallow and diminishes the possibility of burning through the metal. Furthermore, vertical down welding is faster than vertical up. The current used for welding upward on a vertical plate is slightly higher than the current used for welding downward on the same plate. To produce good welds, you must maintain the proper angle between the electrode and the base metal. In vertical down welding, incline the outer end of the electrode downward about 15 degrees from the horizontal while keeping the arc pointing upward toward the deposited molten metal. When vertical down welding requires a weave bead, you should oscillate the electrode. When using E7018 electrodes in the vertical down position, you should modify slightly from the vertical down procedure that use electrodes other than low hydrogen. When vertical down welding with low hydrogen electrodes, you should drag the electrode lightly using a very short arc. Refrain from using a long arc since the weld depends on the molten slag for shielding. Small weaves and stringer beads are preferred to wide weave passes. Use higher amperage with AC than with DC. Point the electrode straight into the joint and tip it forward only a few degrees in the direction of travel. Adjust the amperage in the lower level of the recommended range. I hope this helps you.

By jwright650 (*****)

Date 04-23-2004 15:10

There is a wood stove shop next door and I am told that most of their welds are vertical down to simply seal the stove rather than for strength of the joint.
John Wright

By vonash

Date 04-28-2004 03:40

Down hand and downhill are two different subjects. Down hand welds are simple flat welds. Down hand refers to the easiest position of welding. On the other hand...Downhill welding is out of position welding used to repair undercut, tubular joints, etc. It sounds to me that this is a matter of semantics.
Best regards,
Vonash