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Up Topic Welding Industry / General Welding Discussion / repair valve - weld SA 216 WCB with SA 470 type 410
- - By Quibo (*) Date 11-05-2013 15:17
Gents, I have inconveniences with a swing check valve, between the body and the hinger pin (plug bolt) we have a leakage (steam), to us is urgently avoid the leakage, for that reason I suggest perform a seal weld (fillet weld) between the body of te valve (SA 216 type WCB) and the plug bolt of the hinger pin (SA 470 type 410 - 13%Cr) using  E7018 and PWHT 600°C.

perhaps I'm wrong with the filler metal?

I appreciate your comments

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Attachment: Picture1.jpg (205k)
Attachment: Picture2.jpg (212k)
Parent - - By F-17 (**) Date 11-05-2013 17:07
As a welder I've made similar repair with a non stress relieve procedure, Inconel filler  rod(NiCrefe 3 if memory serves me correctly) was used with preheat and no PWHT
Parent - By Quibo (*) Date 11-05-2013 18:31
Thanks F-17.

I suggest a pre-heat of 150°C. Do you think is ok?
Parent - - By mechan (**) Date 11-05-2013 19:15
I think that I would probably use 309 with pre and post weld heat treatment while keeping an eye on the interpass temperatures. The pre weld heat treatment on 410 is somewhere around 200 C I believe. The 410 is a stainless steel and I can't see using 7018 to make a dissimilar metals weld ... What lbs steam runs through this line?
Parent - By Quibo (*) Date 11-06-2013 12:54
Hi mecham, I agree E7018 is a bad choose, regarding your query, the operating pressure is 8MPa (1160PSI), our goal is replace the valve, unfortunately we have not that valve in our warehouse, and the new valve will come in four months, the seal weld will be a temporary corrective action to avoid the leakage.

I will choose between ENiCrFe3 and E309 to perform the temporary seal weld.
Parent - By swsweld (****) Date 11-07-2013 02:02
ASME B31.3 Table 330.1.1 Preheat Temperatures for P-1 Base Metal Group (SA 216 WCB) only has Recommended Minimum Preheat 70ºC/175ºF for materials 1" thick and greater.

ASME B31.3 Table 331.1.1 Requirements for Heat Treatment (PWHT) is 593–649ºC & 1,100–1,200ºF with a hold time of 2.4 min/mm or 1 hour/inch for materials  greater than 3/4" (20MM).
Parent - - By G.S.Crisi (****) Date 11-07-2013 00:05
I'll take the liberty of making a couple of comments.
1. You say that the valve operating pressure is 1160 psi, but the valve body shows the number 900 on it, which means that the valve design pressure is 900 psi. Are you sure you people have chosen the right valve?
2. Is the valve located on the boiler outlet nozzle to prevent backflow of steam? In this case, good engineering practice recommends to install a stop check valve, which your valve is not. Also in this case, the valve won't fall under ASME B31 (1 or 3, depending on the plant in which the valve is installed) but under ASME Section I (Power boilers). In fact, piping leaving a boiler, up to and including the first valve, falls under ASME Section I. 

Giovanni S. Crisi
Sao Paulo - Brazil
Parent - - By Stringer (***) Date 11-07-2013 00:57
+1 Senor Crisi's question.
Parent - - By swsweld (****) Date 11-07-2013 01:20 Edited 11-09-2013 05:57
In B16.5 Table 2.1.1 Pressure/Temperature Ratings for Group 1.1 Materials the 900 class for A 216 WCB is rated for 2200 psig at -20ºF to 100ºF and 155 psig at 1000ºF so it would depend on the operating pressure and temperature.

At 800ºF it is rated for 1235 psig and at 850ºF it drops to 805 psig.

Edit: Changed 100ºF to 1000ºF
Parent - - By fschweighardt (***) Date 11-07-2013 02:04
@ 1160 psig, the steam temp is right at 565 deg F. for dry steam
Parent - - By swsweld (****) Date 11-07-2013 02:52
Agreed. As long as the temperature is 800ºF and under, the 900 class valve is sufficient....except for the leak.

Also, Conversion of carbides to graphite may occur after prolonged
exposure to temperatures over 427°C (800°F). Note (57)

So operation at or above 800ºF is not advisable according to Table A-1 notes for this material.
Parent - - By G.S.Crisi (****) Date 11-07-2013 19:35
So, Quibo, what's the operating temperature of your valve?

swsweld, is the material rated for 2200 psig at -20ºF to 100ºF and 155 psig at 100ºF? There's some confusion in this statement.

@ 1160 psig, the steam temp is right at 565 deg F. for dry steam. fsch, you're talking of saturated steam, of course, superheated steam may have a higher temperature.

Giovanni S. Crisi
Parent - - By Quibo (*) Date 11-08-2013 12:45
Dear  G S Crisi, the operating pressure is 8.62 MPa and the maximum operating temperature is 223°C, design as per ASME B31.1 (from the designer data sheet)
Parent - By fschweighardt (***) Date 11-08-2013 18:02
I dont see how you can have 1250 PSI and 433 deg F at the same time for any kind of steam
Parent - By swsweld (****) Date 11-09-2013 05:53
Professor Crisi,
It was a typo, sorry for the confusion. It was suppose to be 1000ºF, not 100ºF. I gave the high and low for Class 900 A 216 Gr. WCB in Table 2-1.1 from ASME B 16.5.
- - By lo-hi (**) Date 11-09-2013 00:12
I have seen flanges cut with steam at  60 psi and am wondering how this has survived at this pressure and still look so good.
Parent - - By Quibo (*) Date 11-13-2013 12:44
Gents, our maintenance department avoid weld the bolt, instead, they installed a washer (copper) to prevent the leakage, mi concern now is about the corrosion, please check the attachment; could you please give me suggestions; I think that we will see more leakages in the future due to corrosion?.
Attachment: noleakage.jpg (41k)
Attachment: ParGalvanico.jpg - Par Galvanico - Corrosion (27k)
Parent - - By G.S.Crisi (****) Date 11-13-2013 22:19
In fact, the chance of galvanic corrosion exists, but as you'll receive a new valve in four months, I wouldn't be much concerned about that.
Giovanni S. Crisi
Parent - By Quibo (*) Date 11-14-2013 12:05
Thanks G S Crisi
- - By apwec (*) Date 11-20-2013 16:24 Edited 11-20-2013 16:28
Please note that if that valve is used for temperature higher than 370 degree C (likely since it is for steam service) and you are to perform welding then you shall use a nickel based consumable (e.g. AWS 5.14, ErNiCr-3) instead of E309 due to the fact that the latter may result in embrittlement or cracking for temperatures higher than 370 degree C as specified in SFA-5.4, A7.10, E309. Please have a look at this link: http://www.weldinguide.com/gdanastasiadis/viewtopic.php?f=5&t=32
regards
apwec
Parent - By Quibo (*) Date 11-20-2013 17:58
Thanks a lot apwec
Up Topic Welding Industry / General Welding Discussion / repair valve - weld SA 216 WCB with SA 470 type 410

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