Weldability test for early to mid-1920's steel
Weldability test for early to mid-1920's steel
(OP)
thread725-167138: Welding Pre-1920 Steel to New Steel
unclesyd,
In the referenced thread, you stated, "A quick test to see if it is readily weldable is to make a one side fillet weld,7018 electrode, a 1/4" 2"x2" tab in an inconspicuous place and try to forcibly remove it.
Try first in the hard direction, hitting one time on the weld side. Then hit it from the easy side. It shouldn't break out the hard way. The weld should fail hitting from the easy side."
This sounds like the same test recommended by AISC. However, AISC does not give a very good explanation of the test. Can you please provide a little more detail for this test. Such as, how hard is hard enough for hitting the plate? Is it better to use E70 or E60 electrode? Hard direction is downward? Easy direction is upward? Please explain why a good weld should easily break when hit from the easy side. Is there anything special to look for when the weld has failed when hit on the hard side?
unclesyd,
In the referenced thread, you stated, "A quick test to see if it is readily weldable is to make a one side fillet weld,7018 electrode, a 1/4" 2"x2" tab in an inconspicuous place and try to forcibly remove it.
Try first in the hard direction, hitting one time on the weld side. Then hit it from the easy side. It shouldn't break out the hard way. The weld should fail hitting from the easy side."
This sounds like the same test recommended by AISC. However, AISC does not give a very good explanation of the test. Can you please provide a little more detail for this test. Such as, how hard is hard enough for hitting the plate? Is it better to use E70 or E60 electrode? Hard direction is downward? Easy direction is upward? Please explain why a good weld should easily break when hit from the easy side. Is there anything special to look for when the weld has failed when hit on the hard side?





RE: Weldability test for early to mid-1920's steel
Another test that can be used is to obtain a small sample of the steel to be welded and have it analyzed to determine the chemistry of the steel. The following elements should be included in the report and considered before welding is contemplated:
Carbon: <0.3%
Sulfur: <0.04%
Phosphorous: <0.04%
Once you have determined your actual chemistry does not exceed the limitations noted, you can plug the actual chemistry into a carbon equivalency formula to determine the carbon equivalency. There are several equations that can be used. Each equation has its own guidelines and recommendations. I suggest using the method described in AWS D1.1-2006 (or later) in Annex I.
Best regards - Al
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
RE: Weldability test for early to mid-1920's steel
I not against any of the above suggestions but I you can't lay a bead on the base metal the tests above are mute.
I used the welded tab many times and it hasn't let met down yet. The test is not anymore suggestive than the chemical test proposed. If you actually weld on the subject steel you take out more variables, one in particular is Silicon Stringers.
As stated make the weld on one side and allow to cool. It should bend toward the weld without the bead tearing out from the base metal. If you night want to weld the second tab and try to bend it the hard way, One other test if there is any doubt is the Navy test which is accomplished by welding a 1 1/2" circle spiraling inward, leaving a 1/2" hole in the middle.
Do you see any welding on the column?
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
The 'gold standard' weldability test is to remoive a paperback-sized section. Split the section longways, using a saw -- 'cold-cutting' of the split only. Weld the pieces back togather, using no [ambient] preheat and a less-than 120°F interpass temp. Perform Face and Root Bends per AWS D1.1 or ASME Sect IX -- both are the same. If the bends pass, you have very weldable steel.
If not, use a higher preheat on the next test, and pray a lot.
RE: Weldability test for early to mid-1920's steel
(1) Portable spark tester - expensive but almost zero damage.
(2) Remove and collect scrapings using a clean carbide burr. This is standard practice on buried pipelines. It can be done leaving not more than 0.020" removal.
You might be surprised at the quality of the steel. I once had to repair a 1913 vintage steel on a hydro turbine and it was low carbon and quite weldable.
RE: Weldability test for early to mid-1920's steel
RE: Weldability test for early to mid-1920's steel
brimstoner, I'm not a welding expert so I'll have to look into your two options also. Thank you.
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RE: Weldability test for early to mid-1920's steel
Be real careful when clean the column. I would bet that it has a red lead primer. When you try to weld get the area as clean as possible before attempting to weld.
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
Will all the welding required be on the base plate to column connection?
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
My client hired a company to come in and analyze the composition of the steel in the 1923-ish riveted column. The company did a Positive Material Identification (PMI) Test. According to the testing company, "The material has suitable alloying and iron elements to be categorized as a weldable material..."
The analysis-by-weight showed:
ZN - 0.01% MN - 0.37%
FE - 98.48% ZR - 0.01%
PD - 0.03% CU - 0.32%
NI - 0.18% CR - 0.05%
TI - 0.49% AG - 0.04%
Their recommendation is to use E6010 rod for pitted and dirty areas where the base material cannot be completely prepped/cleaned and E7018 rod where surface preparation can bring the base material to an "as new" condition. The company will be on site to inspect the welding when the work is being performed.
Thank you for all of your comments.
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RE: Weldability test for early to mid-1920's steel
RE: Weldability test for early to mid-1920's steel
In short, I would not stand anywhere near that column when it was cut without ANYTHING definitive for weldability. XRF is good for sorting 304 and 316 stainlesses, Hasteloy, etc. and determining the chrome content of carbon steel. It tells you nothing about the weldability of carbon steel.
RE: Weldability test for early to mid-1920's steel
I have given up trying to disabuse owners and inspection techs (and a few inspection engineers!) of the notion that PMI provides a chemical composition. People see two decimal places on a sophisticated looking display, believe them and then report them.
'Oh well' is right ...
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
Al = 0.011% B = 0.0004% C = 0.20% Cr = 0.008% Cu = 0.016%
Mn = 0.42% Mo = 0.012% Ni = 0.031% P = 0.006% S = 0.021%
Si = 0.007% V = 0.001%
CE = 0.2785 = C + (Mn+Si)/6 + (Cr+Mo+V)/5 + (Cu+Ni)/15
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RE: Weldability test for early to mid-1920's steel
Yes, 6010 is very good for rust & paint. Problem with that is, why do you want to encourage the welder(s) to weld thru garbage?
The weld prep needs to be bare, shiny metal. If they grind a little deep removing the rusty bottom of the pits, it doesn't matter 'in the real world'. They will be welding in that spot -- they can replace the metal that got ground off. The added time will be too small to measure.
If you are supervising the welding, just tell the welder to preheat with a torch "until the moisture comes out". This means that he heats the steel until the condensation ring from the torch combustion [hydrocarbon + O2 = CO2 & H2O] goes away. That is the standard "field term" for a little preheat.
Not that you need it now, but Good Luck.
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
RE: Weldability test for early to mid-1920's steel
The link in my previous post to Lawson Products is for their Cratering 321, not SS, CS welding electrode for dirty steels. It is a little expensive but is well worth the price on some jobs to minimize the prep needed. Your welders will love it if used for nothing but the first pass. You will not have to worry about having any leftovers as these electrodes have legs when it come to welders.
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
The preheat can be determined using the chemistry you have by referring to Annex I of AWS D1.1-2006, 2008, or 2010. Assume a hydrogen level of H2 (not the same as the H4 hydrogen designation used in the electrode classification E7018-H4). H2 is simply an assumption that the contractor will be using electrodes straight from a hermetically seam tin or from an electrode holding oven within 4 hours (limited exposure time). You can also assume a highly restrained joint condition. Be warned that the carbon equivalency formula used in Annex I is different from the one cited in your post.
Using Annex I (AWS D1.1), the steps are as follows:
1) Determine Ceq using the chemical analysis obtained for the sample
2) Assume hydrogen controls to be H2
3) Use table to select the appropriate column to use in the preheat table
The Ceq is listed along the top row, hydrogen control is left vertical column
4) Next page, looking at the preheat table, left column is the level of restraint (high restrain is most conservative), next column is the base metal thickness, moving along the top row, select the letter selected from the first table (, A, B, C, D, or E, with E representing the highest Ceq.).
5) Move down the letter column until you intersect the level of restrain and base metal thickness – Presto! The recommended minimum preheat is listed!
Note: Not all E7018-H4 electrodes are created equal. Most manufacturers make several types of E7018, each with slightly different chemical compositions. The trick is to ensure the manganese content is at least 10 times that of the sulfur to ensure the sulfur will react with the manganese instead of precipitating to the grain boundaries and causing troublesome hot cracks. Your WPS should list the specific welding electrode by AWS specification, classification, manufacturer, and brand name so the erect knows exactly what you require him to use. Allow no substitutions unless the erector can show you the minimum manganese content of his electrode is at least 10 times the sulfur content of the steel being welded.
Best regards - Al
RE: Weldability test for early to mid-1920's steel
Sulfur looks fine, but always check the manganese contained by the electrode used.
Sorry for the slip!
Best regards - Al
RE: Weldability test for early to mid-1920's steel
I've some some very small ones with 325 ton capacity.
http://superbolt.com/index.php
RE: Weldability test for early to mid-1920's steel
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RE: Weldability test for early to mid-1920's steel
It is always good to see a plan come togather.
PS:
Glad you didn't have the column jacked up when the Earthquake hit.
RE: Weldability test for early to mid-1920's steel
www.PeirceEngineering.com
RE: Weldability test for early to mid-1920's steel
www.PeirceEngineering.com
RE: Weldability test for early to mid-1920's steel
RE: Weldability test for early to mid-1920's steel
www.PeirceEngineering.com