Bending machine advise

Date 07-17-2013 16:21

A calibrated coupon bender?? :confused:

Anyway, Triangle Engineering is the only name that comes to mind right away. Nice units. Several different styles but all take the different dies which they also have available.

Have a Great Day, Brent

By jwright650 (*****)

Date 07-17-2013 16:33

Coupon bender probably isn't calibrated, but the tensile puller probably needs to be.

By 803056

Date 07-17-2013 17:51

API? I though all you needed was a flashlight to evaluate a welder for API. Toss the coupon on the ground, if it doesn't break, passed test 1. Test : shine a flashlight on the inner surface, if no light shines through, go to work!

All kidding aside, you will need multiple plunge and dies if you are testing to AWS, ASME, and only one if testing to API 1104. The plunger and die required is a function of the material (P-number for ASME) and the thickness of the coupon (comes into play when testing different diameter pipe with different wall schedules (thickness).

Best regards - Al

By G.S.Crisi (****)

Date 07-22-2013 18:09

Al,
API 1104 deserves more respect!
Giovanni S. Crisi

By welderbrent (*****)

Date 07-22-2013 19:45

Professor,

He did give them more respect...more than they deserve anyway. :lol:

And surely more than he gives the farm code....well....maybe not. That was grasping at straws.

Have a Great Day, Brent

By welderbrent (*****)

Date 07-17-2013 18:03

And with that mention, I recently saw a hydraulic plunger coupon bender with a tensile puller built into the same unit. I know who has it so I will get the name and particulars. Looked like a good unit but I'll bet it goes for about $25,000. But I will make sure for you.

Have a Great Day, Brent

By hillbilly delux (***)

Date 07-19-2013 14:31

Brent did you find out anything from that guy yet? 25k is alittle expensive for my taste. I hoping the 5-6k range is what I can get one for.

By jwright650 (*****)

Date 07-19-2013 14:49 Edited 07-19-2013 14:51

You may have to call to see whether the mfg can give you calibration papers or not...seems like it could be easily calibrated like a Skidmore....but here is a 50T unit that I found for sale online.

Coupon Bend Tester with Tensile Pulling up to 50T

By hillbilly delux (***)

Date 07-19-2013 16:17

I like that one I just don't like the price tag. Ooch

By welderbrent (*****)

Date 07-19-2013 17:23

I am on the other side of the state for one of my son's wedding. Can't contact right now, no information.

If you look at the manufactured wrap arounds you will find them very expensive. Even the manufactured plungers are expensive enough that I also have built my own. I mentioned the others because of the mention of a need for calibration. When you mix both a coupon bender and a tensile tester into one unit it is not going to be cheap.

The only part of this that would require calibration should be the gauge for the tensile.

At any rate, I will get it asap.

Have a Great Day, Brent

By jarsanb (***)

Date 07-20-2013 16:46

Tinius Olsen in the lab and Fischer Engineering bend tester in the truck. Fischer is very affordable.

http://www.fischerengr.com/BT1C.htm
http://www.fischerengr.com/TT1.htm

By MMyers

Date 07-22-2013 15:10

My first job out of school was for Glen. I got quite a bit of experience working in his shop. I'd recommend his equipment without hesitation if it met the technical requirements of the project. There are also other models which have interchangible mandrels and adjustable rolls which are nice if those capabilities are needed.

By 803056

Date 07-19-2013 16:52

I built my bending machines. I have two, one is a standard plunger and die type machine that employs a hydraulic bottle jack to move the bottom die. The newer machine is a wrap around type that I designed and built. It is relatively compact and I can check it as baggage when flying.

The bending machine does not have to be complicated. With a little thought, most people can figure out a way to build a machine that conforms to the requirements of the applicable welding standard.

Since we are talking about bending machines to perform the guided bend tests, remember that with the exception API 1104, different bend radii are required for different materials that have different properties and for different coupon thicknesses. More than once I have discovered the testing lab used the wrong bend radius because they only had one die set. Opps!

Best regards - Al

By jwright650 (*****)

Date 07-19-2013 17:05

I think the tensile puller may prove a bit more challenging to build vs the coupon bender. I say challenging, I realize that there are some very creative people in our midst so I won't say that it can't be done...but to use a homemade device for tensile pulls may prove challenging on the calibration end of things when trying to create the paperwork annually for the sake of approving auditors.

By MRWeldSoCal (***)

Date 07-19-2013 17:13

I cant see how you would calibrate the breaking pressure and lock it in. Do they make a hydraulic check valve that will hold it?

By MRWeldSoCal (***)

Date 07-19-2013 17:12

Al-
I would really like to see this tiny wrap around bender youre talking about. Got any photos?

-Jordan

By 803056

Date 07-20-2013 00:35 Edited 07-20-2013 00:37

I have tried to take a photograph of the machine, but it never shows how it is constructed very well.

As for tensile testing, it is usually less expensive to send the samples out to be tested than to maintain the machine and calibrations.

I had a tensile tester and got rid of it due to the cost and floor space required. In all seriousness, how many WPSs will the average CWI qualify in a year?

Al

By welderbrent (*****)

Date 07-20-2013 03:54

Most of the time we qualify welders to D1.1 Pre-Qualified WPS's and write Pre-Approved WPS's. The need to qualify a PQR/WPS has only come my way once in the past 5 years. Not very cost efficient if you have your own tensile tester.

Have a Great Day, Brent

By hillbilly delux (***)

Date 07-21-2013 14:11

In API testing of inservice welder qualifications (which I do a lot of) requires a tensile test. Building a portable test trailer to qualify welders out of. I am looking for a dual service destructive testing machine. One that does bends and tensiles both from the same machine.

By CWI555

Date 07-21-2013 22:08 Edited 07-21-2013 22:23

I would advise you to separate the two or be prepared to pony up some $$$$$$$. I would also be concerned about a portable tensile tester.
I don't have the current 1104 handy, but as of 2005 (last time I needed 1104), it was better to utilize this paragraph and omit the tensile all together for field testing:
6.5.2 Tensile-strength, Nick-break, and Bend-test
Procedures for Butt Welds
The specimens shall be prepared for tensile-strength, Nickbreak
and bend tests, and the tests shall be performed as
described in 5.6. However, for the purpose of welder qualification,
it is not necessary to calculate the tensile strength of
the coupons. The tensile strength test may even be omitted, in
which case the specimens designated for the test shall be subjected
to the Nick-break test.

It's been my experience that the manufacturing techniques allowed in 1104 for welder qualifications is a setup for failure on everyone's part when they include tensile test. Your not qualifying a weld procedure, the WPS should have already been qualified prior to the welding test.

6.1 GENERAL
The purpose of the welder qualification test is to determine
the ability of welders to make sound butt or fillet welds using
previously qualified procedures.

A nick break test is far more applicable given that. Pulling a tensile is only 'part' of a procedure qualification, and can lead to a false sense of security if the welder 'burned it in' outside of parameters of the Previously qualified WPS.

A nick break test can fail on the same weld that passed a tensile pull. Once you get into that tender trap, your set up for failure as well.

My opinion for what it's worth.

post script: API may have mandated the tensile since 05, you will have to verify it against your particular edition. However, if that is the case, you would still be better off to send those to a lab rather than open yourself up to the pitfalls of doing it yourself.

By MRWeldSoCal (***)

Date 07-22-2013 14:04

Where I work we do some exotic metals here an there and i have already written 3 PQR/WPS's in the last 3 months all involing tensile pulls, when it rains it pours I guess

By JTMcC

Date 07-22-2013 22:17

803056 says:

"The tensile test used by API 1104 for the qualification of the welder is simple one more way of breaking the welder's samples for visual evaluation. The tensile test (when used for performance qualification) doe not involve comparing the tensile strength of the welded joint to any standard, i.e., there are no load/area calculations involved.

Best regards - Al"

I must really be missing something here because that makes no sense to me.

I've seen several hundreds of welder quals in mainline, station and distribution work. A tensile pull that breaks in the weld is an immediate fail for the welder, he's rolling up the truck and driving away unemployed.
Every tensile machine I've seen has had a gage, the force at the point of breaking is recorded on the welders papers, along with the elongation. There really are calculations made.

Nicks breaks ARE a way of visually inspecting the weld metal.

Like I said, I may of missed it.

J

By 803056

Date 07-23-2013 00:40 Edited 07-23-2013 00:45

6.5.3 Tensile-Strength Test Requirements for
Butt Welds
For the tensile-strength test, if any of the reduced-section
specimens or the full-section specimen breaks in the weld or
at the junction of the weld and the parent material and fails to
meet the soundness requirements of 5.6.3.3, the welder shall
be disqualified.

The above excerpt is from the section in API 1104 addressing welder performance qualification. Note that it says nothing about "Tensile strength." It says the if the sample fails in the weld or at the juncture of the weld and filler metal, it must meet the soundness requirements of 5.6.3.3, which is the same as the nick break test. See the following:

5.6.3.3 Requirements
The exposed surfaces of each nick-break specimen shall
show complete penetration and fusion. The greatest dimension
of any gas pocket shall not exceed 1/16 in. (1.6 mm), and
the combined area of all gas pockets shall not exceed 2% of
the exposed surface area. Slag inclusions shall not be
more than 1/32 in. (0.8 mm) in depth and shall not be more
than 1/8 in. (3 mm) or one-half the nominal wall thickness in
length, whichever is smaller. There shall be at least 1/2 in.
(13 mm) separation between adjacent slag inclusions. The
dimensions should be measured as shown in Figure 8.
Fisheyes, as defined in AWS A3.0, are not cause for rejection.

Again, I see no criteria saying the "tensile" test has to meet any tensile strength requirements, minimum strength, elongation, etc. Do you see something I'm missing? No need for silly gages, calibration, calculations, UTS, or elongation. Maybe someone didn't read the standard, but should have. Maybe they didn't know the difference between qualifying the welder and qualifying the WPS.

Apparently API 1104 doesn't make sense to a lot of other people. Glad to see you are in my corner JT. Bring on the Farm Code!

Best regards - Al :roll:

By JTMcC

Date 07-23-2013 02:46

Right, you are quoting from API 1104. But I'm talking about real world welder testing conditions on the ground. I certainly understand the differences between qualifying a welder and qualifying a procedure.

In the sectors I mentioned, I've never seen API 1104 used as a bible like it seems D1.1 is. I've owned several copies of 11-4 over the last 20+ years but they are pretty much unused.

I've mentioned many times, 1104 , to the welder in the field, is almost worthless. The gas/oil company will graciously give every welder a 3 ring binder, some reasonable size, some really large. THOSE specs are what the welder and the contractor lives or dies by.
Every company is a little different, just like the discussion about time between bead and HP. It matters not at all what 1104 says or doesn't say about the time. What does matter is if the gas company calls it a cutout after 4 minutes 30 seconds, then it's a cutout. And they all will specify that detail plus several hundreds of pages of others that very likely have no mention in 1104.

To think that 1104 is a defining standard in mainline/distribution/stations or even gathering systems shows lack of real life hours spent in those fields. The company quality manual, joining specs, rules and regs are where the weight lies.

By the same token I've seen a few welders argue inspection by quotiing allowable limits in 1104. That's just as goofy. If Kinder-Gentler Gas Transmission Co Inc says that 1/16" internal undercut is a repair, and gets the welders money, then at that point 1104 is about as pertinent as the latest issue of Field and Stream. The weld gets a flag and the welder is gone.

I won't even begin to think I can debate the finer or even the course points of 1104 with anybody.
But I would try once more to point out that it is not the standard of weld workmanship or joint configuration, welder quals, production weld acceptability, preheat, rod size, speed of progression or really anything else in my small slice of the welding community.

I do have a fairly decent handle on the welder qual tests that are currently used across the country (again in my field only) and the force/elongation numbers are written down pretty regular on test papers for welders. Regardless of what 1104 says.

Just my observations of actual work practice vs the funny little book they print in Houston.

J

By 803056

Date 07-23-2013 16:11

Again, you and I are singing from the same page regarding the usefulness of API 1104.

It is a cover your butt type of standard. It is out there, but no one really believes it. Farm Code all the way.

From what I've seen, nearly every company ignores most of it. Welders for the most part have never seen it. Nobody actually reads it.

Al

By jarsanb (***)

Date 07-23-2013 16:34

The D.O.T. and local State Utility Commissions read it, and therefore the system owner/operator reads it. As laxed as it is there are some more stringent - pain in the rear - variables that need to be addressed that many fab shops/contractors are not prepared for if they are more familiar with AWS/ASME practices...such as in procedure development and usage. Example, you can't use this procedure for this pass and that procedure for that pass stuff. And therefore welder qualification also follows this pattern. And, like everything else, it gets more stringent down the food chain. Keep in mind, you only use certain sections of API 1104 because they are referenced by the Code of Federal Regulations, then in more stringent detail in state added rules. There is very little direction given on HOW to do things. As Al has mentioned before, it allows you to swim or sink. I'm pretty sure the pipeline industry prefers it this way. With many of the pain in the rear variables it does have a tendancy to dissuade new contractors from taking a piece of the pie - after they lost their ass when they tried.

By 803056

Date 07-23-2013 17:11

So, it is out there just in case something goes boom in the night. Then the regulators have something to point their long skinny fingers to and say, "See you didn't follow the standard!"

OK, I stirred the pot, but there were not many takers. I thought there would be more defenders of API. Even with my prodding and poking it seems only a few people are willing to take a stand to defend the standard.

It has served the industry for many years. We have pipelines buried in the ground throughout the United States and around the world. They have performed their intended functions here in the US since the 1940s, some even earlier. They has served us well. API 1104 has not adopted the same cook book approach as did AWS D1.1. Instead, like ASME B&PV code, it leaves it up the the designers and constructors to design and build pipelines that will provide years of safe service. It is the company's responsibility to develop systems that will ensure the pipeline will transport the liquids safely. It also means that the Owner is responsible to maintain those pipelines so they can continue to perform in a safe manner.

API 1104 is not a design manual and it does not tell the user how to construct the pipeline. It serves as a framework that can be used by the Owner, designer, and contractor. Each entity has to have the expertise to fulfill their obligations as per the project specification as well as local, state, and federal laws. It provides everyone the latitude to use their expertise to construct a pipeline using the latest innovations available, but it also exposes the "team" to the risks associated with innovation. The Owner, designer, and contractor have to realize that meeting the minimum requirements may not be sufficient to ensure their longevity and profitability.

Al