No, cause their pipe sucks in my opinion. I hae welded on pipe from so many different countries I can't name them all, but that chinese pipe aint anywhere near what I'd call "reliable" when it comes to how it welds. You'll pull porosity, have laminations, crap loads of scale, an if you're lucky, the IDs of the joints you're welding will be concentric enough to put a bead in without much hassle. I know that some of the companies over there are starting to get it right but they're the in the minority.
Why?? Plain and simple, point blank, Chinese steel SUCKS! I have rejected many loads of Chinese steel for no penetration in the seam welds. PT them and they bleed like a stuck pig, splits galore. Very poor weldability, porosity, laminations, splits at the corner radius ect.
Add to that the fact that more and more, customers are requiring that no Chinese steel be used when manufacturing their product and we give the customer what they want.
Try this on for size. We had a job at one time for a customer in CHINA. Guess what the customer spec said? USA steel only. WTF!?!? China did not even want their own steel! Go figure.
Next, two words. Radioactive steel!! Enough said.
Chinese steel SUCKS POND SCUM.
jrw159.
By Nanjing
Date 12-20-2009 02:26
What an imagination you have.
All facts there Stu.
jrw159
I think it would be wise to treat it all like pre 70ERW. In the last four years I've witnessed seam pipe and examined several pieces of "modern" seam welded pipe with LOF in the seams.
ASTM312 for instance allows up to 20% repair of the seams before it's rejected outright. If you think about it, thats a fairly broad allowance.
Taking that into account, if the application is critical, it would be a good engineering practice not to use seamed pipe at all. However; the cost difference is usually viewed by people who don't really understand that. In light of that, it's not unusual to see seamed pipe used in critical apps.
The last time I checked, the criteria in most pipe standards for NDE is non-mandatory. It's a value added, and a lot of procurment folks don't know, and unless told, don't care what the difference is. 20-30 years ago, you could count on pride and good workmanship, now you cannot.
China is coming into it's own in the age of lean lean six sigma. It's been my observation that a lot of the ASTM/ASME/API/EU/BS etc specifications contain many assumptions of quality. For instance, many specs have an allowance of 12.5 percent +- for wall thickness. I've seen a pile of pipe come in from China at -10 to -12 percent T. Still in spec, but definetly not following the intent of that allowance. They are following the lean lean idea that the Japanese/EU/America put out, only they do not care about the quality aspect.
Ideally that T allowance would be taken right down the middle, but it is not.
If it requires minimum 10 percent nickel, you'll get somewhere between 9.999 and 10.1, if it requires minimum -12.5 percent, your going to get that to.
Therein is what I believe is the real problem with Chinese steel. China is at it's heart a communist nation. You don't question the boss so to speak. Combine that with corruption, and you will have a crappy product. You cannot attempt to follow the bare minimums and not find yourself on the wrong side of them frequently.
This is where they fail to understand the purpose of those tolorances. The tolorances are there with the Assumption that a manufacture is shooting for the middle road, not the minimum road.
So when they find themselve on the wrong side of the spec, the 'don't say no' and 'corruption' cultures come together and they simply ship it out and hope for the best.
Thats my take on the matter, and why I feel good engineering practices should be mandated rather than assumed.
Regards,
Gerald