your experiences with strip/ribbon weld overlay

[vesselfab]

We have been in the process of expanding our business and plant capacity moving towards heavier carbon steel and chrome-moly vessels with clad or weld overlaid internal surfaces. Being an old skeptic by nature, I am interested in opinions/experiences with 50mm stip overlay process, primarily austenetic stainless, especially on Cr-Mo.

 

[rmw]

I have seen it used quite extensively by high pressure HX manufacturers for tubesheet overlaying. If my memory is correct it was on LF2 or LF3 forgings and was 308 or 309 SS ribbon. The resultant overlay was always UT'd and defects were rarely found. Defects would be critical in that application. I know that Yuba Heat Transfer and Thermal Engineering International both use that method. Some of the others that might have (Struthers Wells, EFCO) are no longer around (but not because of the overlay process I hasten to add).

rmw

 

[metengr]

vesselfab;
There was an excellent article in the January, 2007 issue of "Svetsaren" The ESAB Welding and Cutting Journal, Volume 62, No. 1.

The article is titled ""Strip Cladding under the Spotlight". This article would provide exactly what you are looking for in your post. The article that was most interesting to me was on page 10;

"Disbonding of Austenitic Weld Overlays in Hydroprocessing Applications",

 

[LSThill]

vesselfab (Mechanical)

additional information

http://www.esab.es/global/en/news/upload/Svetsaren_1_2007.pdf

 

[vesselguy]

I had 4 2.25Cr hydrotreaters built by Belleli back in 99 with all strip W.O. via the ESW process. They had to provide us with hydrogen disbonding test results as part of the WPS acceptance process. I was fortunate to had a chance to see it in action. It was fast and saved time on our delivery schedule. If we insisted on doing the old fashion standard 2 pass (ie. 309L then 308), there was no way we could have delivered the vessels in time. All of the W.O. passed 100% UT, min undiluted thickness, and ferite testing.

Why be skeptical? Use it, but insist on hydrogen disbonding test results as assurance.

 

[stanweld]

Strip overlays have been done for years. Problems can occur. One of the first SAW, 50 mm strip overlays in the US that I was involved with in 1981 developed microporosity due to fluctuating voltage from one of four power supplies - required lots of rework but full fusion was never a problem.

The fusion problems of the '70s have essentially been resolved.

Today's ESW strip overlay process is especially productive and highly capable of providing ful fusion.

 

[vesselfab]

I would like to thank you gentlemen for taking the time to answer my questions. We have done the 2 pass SAW for years when we have to, but business is forcing us to do more and more. We are definately taking a serious look at the ESW ribbon method.

Again, thanks for your insight