Your not likely to find a WPS that references rebar or cold rolled. You need to know something about their chemistry and mechanical properties.
Try useing some AISI or ASTM tags so you know more about the properties of the base material. I am guessing you are not intending to weld low alloy or SS material. You may find they are of very similar chemistry and mechanicals.
Most plain Carbon cold rolled steel would be something like AISI 1018.
For rebar ASTM has spec's
ASTM A 615 Deformed and plain carbon-steel bars for concrete reinforcement
Once you know what to look for you can refine your search. I do not know your application so be aware most rebar when being used as REBAR in concrete is not suitable for welding.
Why is that welded rebar cannot be used in concrete? whare does that come from?
It is not recommended because welding can reduce the fatigue life of the rebar. It is not allowed at all in prestressed concrete formations.
The above would apply to Civil Engineering code requirements not Welding.
ADP,
ASTM A706 is more welder friendly that A615. ASTM A615 is the standard type of rebar used for reinforcement in concrete building
structures. The most commonly used grade is Grade 60 (Fy = 60 ksi), but is also available in Grade 40 and Grade 75. The C.E. (carbon equivalent) of ASTM A615 rebar is not controlled and must be determined through chemical analysis. This analysis is usually reported on the product Material Test Report. The C.E. of ASTM A615 rebar generally falls between 0.6 and 0.7…so preheat is almost always required for welding.
ASTM A706 is a rebar intended for applications requiring controlled tensile properties (i.e. seismic applications) and applications requiring enhanced weldability. It is available in only one grade, Grade 60 (Fy = 60 ksi). ASTM A496 (DBA) is the standard specification for Deformed Bar Anchors. The C.E. of ASTM A706 is controlled to provide a carbon equivalent not to exceed
0.55%. Therefore no preheat is required for commonly used bar sizes (up to 3/4”).
ASTM A496 Deformed Bar Anchors are designed to be electric arc welded to the base material with a stud gun, similar to a headed shear stud. The minimum yield strength is Fy = 70 ksi.
swnorris,
Thank you so much for the comprehensive response. Your response also prompts some questions.
1. With ASTM A706 do you mig weld it (as ive been instructed by my local weld supply house) with Argon mix? Can it be stick welded?
2. With ASTM A615 say you did weld it (mig with a gas mix) and didnt know the carbon content what could/would happen? can it be stick welded?
3. If you weld ASTM A706 to A36 plate (or even grade 50 steel) what should the correct method be? stick, mig etc?
Thanks again
Austin,
One needs to first be aware that when it comes to re-bar you should have D1.4 handy.
According to D1.4, Clause 1.4.1: "Welding shall be performed with shielded metal arc welding (SMAW), gas metal arc welding (GMAW), or flux cored arc welding (FCAW)." This would exclude GMAW-S (short arc) unless qualified with a PQR and approved by the engineer.
Next, according to Table 5.1 of D1.4 you do have a difference in filler metals. The 615 can be welded with 70 series fillers in the three mentioned processes. A706 is to be welded with 80 series fillers. Low Hydrogen stick electrodes and appropriate gases for the wire processes.
And don't forget swnorris's comment about pre-heat for the 615.
Have a Great Day, Brent
Brent,
Thanks so much. Lots of good info you given me.
Austin,
For the record, Scott makes a good point that shows up a little further down this thread. I answered you briefly which may lead to a slight misunderstanding.
Your third question, the weld could be made with 7018 because you can go to the weakest material, the A-36. You can also use the 8018 as I originally posted. Any application to higher alloy steels or A 706 to 706 would go with the 8018. So, to the best of my knowledge, you can't go wrong with 8018 on A706, but it is not mandatory in ALL circumstances. Compare Table 2.1 with Table 5.1. Much depends upon the type of joint, materials used, the type of stresses in use, etc.
Hopefully you have or are getting D1.4 Structural Welding Code- Reinforcing Steel.
Have a Great Day, Brent
Not to be nit picking, but... While a lot of plain carbon cold rolled steel is something like 1018, it could be 1040 or something else, as cold rolling is only a finishing process and has nothing to do with chemistry or mechanical properties. A little more information would be a good idea before welding on it.
What you say is true, what I dont get is where I said it was 1018, I believe i referred to AISI and gave 1018 as an example.
ADP,
I would add a little to what Ron said about the cold rolled steel since that was the basis of your question. Remember, or research, Cold roll and Hot roll are pretty much the same. Carbon content, other alloys, tensile strength, and classification. The main difference is in the production technique which will give the Cold Roll better mechanical properties (depending upon what you are looking for) and a better surface finish for most applications (truer roundness, size, no mill scale, etc).
I may have over simplified the differences a little, but I think it is accurate enough for the topic of discussion.
Thus, taking your MTR in hand you should be able to come up with a WPS that will work for welding re-bar to Cold Roll Steel.
swnorris made a good point about the difference between A 706 and the 615 re-bars. From personal experience, in my area of AZ, City Building Officials and Engineers are now calling for the use of A706 (Weldable Re-bar, not that others aren't) in almost every case where welding will be involved.
Combine their two comments and you have a combination that should not be a written procedure nor application of weld problem.
Have a Great Day, Brent
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