E 7048

Date 08-27-2008 17:43

7048 is still listed in SFA 5.1.
It says it is suitable for vertical down welding and other positions.
I have never run across it, but I learn something new every day here.

By dbigkahunna (****)

Date 08-27-2008 22:39

You want to run it really hot and fast.
Use a match strike motion starting below where you want to weld then bringing the rod into the puddle to get the rod hot before welding or you will get GP at the start.
Once it gets started, run it like you are caulking. No pushing.
On a Lincoln SA 200 240 and 70
Travel on this rod can be 18-24 IPM
Back in my drinkin days this rod was made by Philips in the Netherlands. It was used on repairs on loaded lines when you could still weld patches on without sleeves. You were supposed to get the properties of LH without the penetration. Once you get the starting technique, it is almost like running Jet. I could only do a filet with it. Tried doing butt welds with it, but too much porosity. Also the flux was hard to remove. They also had a shelf life like 18 months.
BABRt's

By Superflux (****)

Date 08-29-2008 14:26

Thanks Bill and Kahunna for your responses. The 7048 was distributed by Washington Alloy Co. Other than the fast freeze charactristic of the slag and 6010 kinda sound it made...I found little if any advantage over "cheating with Lo-Hi" and running 7018 down. Although not scientific, the beads' appearance did not indicate any appreciable deposition and with the high amperages used and suggested in this forum, I can see in my minds eye the size of holes that's gonna get blown in that tank shell. Good thing it has cleaned of flammables (hate it when your current project is on "live breaking news"!!). The Boilermaker Supt. wanted this procedure for low heat input on a large tank repair and modification project. Only tested the one welder, was sorta hoping we would get some more testers in the booth just to see how others would fare with this rod.
As always in this line of work, ya never know what's gonna get thrown at you and how challenging someone's creative solution to non-existent problems (ie. molehills into mountains) can be.

By dbigkahunna (****)

Date 08-29-2008 20:26

If this is on a tank repair, and they are worried about heat input, just use smaller rods and bead the cap. What is the steel group of the base metal?
Regardless what they are telling you, the 7048 is NOT an easy rod to run. It stinks on butt welds. Really stinks.
BABRt's

By Superflux (****)

Date 09-02-2008 14:27

dbigK,
I am but lowly inspector and can only test accordingly to the whims and wishes of those further up the food chain and way beyond my paygrade. My limited trials with 7048 has yet to impress me.
The new plate ordered is 516 gr. 60. Yeah, and the other part of the gig is I'm dealing with Boilermakers/Tankies, and they are a high amperage, go gitter mind set. Granted, this is good from a pounds per hour point of view, but when it comes to old tank retro-fit....ah the horror! Fortunately, I'm working with UA pipefitters in a remote shop and this is just a partime/fill-in deal to help out the field division. Every time I come accross bone headed ideas like this, it reinforces my decision to have "hung-up the hood"! When you have to make a project like that fun, it becomes challenging...Herculean.
Thanks again for the input.

By dbigkahunna (****)

Date 09-02-2008 14:41

Back when this rod was being pushed one of the advantages was low hydrogen welds, low disposition rates and high speed. On 653 repairs, low hydrogen is only required on shell thickness >0.500 which does away with the supposed advantages of the 7048 rod.
If the bone heads are set on using this, the welders need to grind the starts almost to a feather. The PH's would go to the bottom. Also on the edges the slag is really hard to remove with just a brush when in the convex profile. Once it flattens out is just gets hard. Lightly hit the edge of each side of the bead before depositing the next pass. You cannot burn the slag out with the next pass. If it is on the weld , it will be in the weld.
I don't envy what is ahead of you. Just work with the welders and be sure they understand this is NOT Excalibur or Atom Arc. Hoods will be thrown.
BABRt's

By Superflux (****)

Date 09-02-2008 18:09

Back when this tank was built, apparently there weren't no need for paper trails, MTR's, welder certs etc. Rumor has it that it is made of boiler plate. Fortunately, as I mentioned earlier, I am in the shop, but tomorrrow, I'll probably be testing some more Tankies for the retro-fit at "#*^&%$" Refinery. Good thing for them that the test is in a "sterile and controled" environment. I love my job, sux to be them!

By dbigkahunna (****)

Date 09-03-2008 01:54

Was analysis done on the base material as required by API 653 7.3.1.2?
It seems to me they are using a high grade material to be used on a unknown base material. If this is a cut down reerect from the mid 1950' sit could be steel from a riveted tank.