Re: [MW:17850] Regarding baking of low hydrogen electrodes

Dear Sridhar,
                   thanks for swift reply,now its clear to me.

--
Thanks & Regards
Shashi

On Fri, May 31, 2013 at 12:46 PM, c sridhar <sridhar305@yahoo.com> wrote:

After  breaking the seal and considerable gap of time, re-baking is to be done for LH type electrodes,

as the electrodes would have picked up moisture by then  when exposed to the humid conditions. 

 

All low Hydrogen type electrodes may have > 10 ml  & < 15 ml of H2 per 100 grams of weld (except for

H4 type LH  electrodes, where it is less than 3 to 4 ml. of H2 ) and re drying  to be done  to reduce the H2 level   to < 10 ml.by holding them at 300 deg. C for 2 hrs. in the oven. 

Drying should be done only once and prolonged drying  (or) more drying cycles will whither the flux

coating and may produce cracks  on the coating surface and make the electrodes unusable.

 

The electrodes are then held in Holding oven (if required) at 100-150 deg.C,  if backed in large quantity

and to avoid repeated re-baking (re-cycling) and damage to the coating if  unused for any prolonged

period like unforeseen circumstances, holidays etc

Welders are supposed to use portable (kept at 100 deg. C or so) for actual welding. These ovens also know as re-fill ovens as the electrodes are re-filled after  every 2 hrs. of welding work or less. 

 

Sridhar.

 

 

---

From: shashi <slpo1980@gmail.com>
To: materials-welding@googlegroups.com
Sent: Friday, 31 May 2013 11:44 AM
Subject: [MW:17843] Regarding baking of low hydrogen electrodes

Dear experts,

                        I have query regarding baking of low hydrogen electrode, is there any universal rule/standard governing these as in some project rebaking is not allowed whereas in some project re-baking can be done only 1 or 2 times.

Query1: how many time can we bake the low hydrogen electrodes, if over baked what will be the consequence.

 

Query2: after baking we transferred to holding oven maintain at 150 ° C,  how long we will keep electrodes at these temperature

Regards

shashi

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Re: [MW:17851] Radiographic Film Interpretation Excess Penetration..

Dear bijoy

I think you are kidding, It's  not a secret. You may hear about STEREO-RADIOGRAPHY!

Regards

On Fri, May 31, 2013 at 1:19 PM, Nandesh Kumar <nandeshkumar@rocketmail.com> wrote:

Parallax is a method to 'estimate' the depth of the discontinuity in the weld; not for the measurement of volumetric flaws. ವಂದನೆಗಳೊಂದಿಗೆ / Best regards, Nandesh Kumar Arasappa P.S. : Please don't print this e-mail unless you really need to. --- On Thu, 30/5/13, Jean Staton <Jean.Staton@metco-ndt.com> wrote: From: Jean Staton <Jean.Staton@metco-ndt.com> Subject: RE: [MW:17841] Radiographic Film Interpretation Excess Penetration.. To: "materials-welding@googlegroups.com" <materials-welding@googlegroups.com> Date: Thursday, 30 May, 2013, 5:54 PM It my be possible to perform a Paralax method.   From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of bijoy joseph Sent: Thursday, May 30, 2013 1:52 AM To: materials-welding@googlegroups.com Subject: Re: [MW:17838] Radiographic Film Interpretation Excess Penetration..   dear meisam, Please explain your  secret technique to measure the 3 dimensional defect in RT  rgds   On Mon, May 27, 2013 at 5:31 PM, meisam shokri arfaei <meisamshokri@gmail.com> wrote: Dear friend, At first look we should say it is not practical generally to measure the excess penetration from RT film because it is 2-dimensional. But some techniques may be employ to do this measurement by RT. Also some joints may be shown their excess penetration on RT film If you didn't use such techniques and your joint is simple butt joint, so your answer is NO.    Regards   On Mon, May 27, 2013 at 12:54 PM, Dominic v.k.dominic <v.k.dominic@gmail.com> wrote: Dear friend , that code is API 1104.. my question is excess penetration how is measuring the rt film like ruler scale..your knowledge it is possible   Thanks Dominic V.K.     On Mon, May 27, 2013 at 10:28 AM, Babur Khan <mbabur.bwp@gmail.com> wrote: Dear friend, 1st you mention construction code which applicable if ASME B31.3-2008 then see Table 341.3.2 Acceptance Criteria for Welds and Examination Methods for Evaluating Weld Imperfections as per this L Height of reinforcement or internal protrusion [Note (8)] in For T w, mm (in.) Height, mm (in.) any plane through the weld shall be within limits of the applicable height value in the tabulation at right, ≤ 6 (1⁄4) ≤ 1.5 (1⁄16) except as provided in Note (9). Weld metal shall merge > 6 (1⁄4), ≤ 13 (1⁄2) ≤ 3 (1⁄8) smoothly into the component surfaces. > 13 (1⁄2), ≤ 25 (1) ≤ 4 (5⁄32) > 25 (1) ≤ 5 (3⁄16) M Height of reinforcement or internal protrusion [Note (8)] Limit is twice the value applicable for L above as described in L. Note (9) does not apply. so and same like API 1104 have criteria     On Mon, May 27, 2013 at 9:28 AM, Dominic v.k.dominic <v.k.dominic@gmail.com> wrote: Dear Expertise,   I have this issue please anyone clarify me, One QA/QC- Inspector 20 years Experience person  he rejected one 24" pipe line  RT film   because of excessive penetration by measuring the dimension with a ruler and required the joint to be repaired.. This is Acceptable or Not Acceptable. if Acceptable where is mentioned the code? Please clarify me, Because my management take this issue very serious     Best Regards  Dominic V.K.   -- To post to this group, send email to materials-welding@googlegroups.com To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com For more options, visit this group's bolg at http://materials-welding.blogspot.com/ http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm   The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents. --- You received this message because you are subscribed to the Google Groups "Materials & Welding" group. To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com. 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Re: [MW:17852] Welding and cladding SA-516 Gr. 60 + AISI 410S

Hi! I would like to share my experience with 410S overlay on CS i) If you try to overlay 410S/410  chemistry on Cs,  It does not pass in bend during bend test as per ASME sec IX (It cracks) if client is very stringent and he requires only 410S chemistry in such case you require to take waiver  for Bend test which is job specific    You can try with 410 consumable with low C% less than 0.04 (Which is very difficult to get( Some time even 309MoL/309L barrier  with subsequent layer by 410 chemistry being used)   ii) Some time you may use 410 Ni Mo to get satisfactory bend test results However weld chemistry will have Ni ,Mo but major element will of Cr which will be in the range of 410   iii) However my experience is a) ",client accepts the 309L/309MoL for 410 clad restoration and b)  for high temp service (Like coke drum)client accepts the NiCrFe3 or NiCrMo3 chemistry where there is no problem of crack during bend test   In such case PWHT temp governs as per  UCS56 of ASME Sec VIII Regards   Hegde P.B.     --- On Fri, 31/5/13, Ramin Kondori <raminkondori if clie@gmail.c would like tostry shareIom> wrote:s ring bend test as From: Ramin Kondori <raminkondori@gmail.com> Subject: Re: [MW:17849] Welding and cladding SA-516 Gr. 60 + AISI 410S To: materials-welding@googlegroups.com Date: Friday, 31 May, 2013, 2:54 PM 410S itself is not martensite but this is when you have a weld metal which is only consisted of 410S not mixture of carbon steel and 410S... Dilution will occur and chemical analysis of the weld will be totally different than 410S. When 410S is deposited on carbon steels, depending on the carbon content of the substrate, the resulted weld metal will be something new rather than 410S... Cr wil be around 6-8% and There will be martensite in resulted weld metal. This martensite, if exceeds certain levels will be problematic and should be avoided. Some references recommend a maximum of 30% martensite in the weld metal microstructure and some allow up to 50% martensite in the microstructure. This is only achievable by preheat... One safe method is to use a buffer layer such as 309L or 310 followed by a low heat input process like Pulsed-MIG for depositing the 410 (or 410S if it is available) layer to avoid a layer which is over-alloyed by Cr... Depending on the client, this becomes a difficult task as the client does not accept variations in Cr levels in top layer of overlay. So clear every thing with the client or inspector before proceeding. Regards Ramin Kondori On 5/30/13, c.nopadon@vipco-thai.com <c.nopadon@vipco-thai.com> wrote: > My memory is stainless steel grade 410 is martensitic and suffix S is > related to welding issue. > Regards, > C.Nopadon > > -----Original Message----- > From: materials-welding@googlegroups.com > [mailto:materials-welding@googlegroups.com] On Behalf Of kannayeram > gnanapandithan > Sent: Wednesday, May 29, 2013 12:29 PM > To: materials-welding@googlegroups.com > Subject: Re: [MW:17828] Welding and cladding SA-516 Gr. 60 + AISI 410S > >  SS 410S is not martensitic > > On 5/28/13, Ramin Kondori <raminkondori@gmail.com> wrote: >> *Dear Branko:* >> >> Depositing AISI 410S on A516 will produce a martensitic weld overlay >> which is prone to cracking even during welding. There Are two solutions: >> >>    1. Using a buffer layer (intermediate layer) of E309L or even E310L on >>    A516 and then Depositing 410S >>    2. Applying preheat of min 250-300 C which makes it a very hard job >>    though it may seem less expensive >> >> In first scenario, you do not need any preheat but I do not recommend >> using SAW for 410S layer since it may melt through the buffer layer >> and reach >> A516 which maybe, maybe causes problems. You can use GMAW with Ar+2%o2 >> or >> Ar+3%CO2. Do not forget the Preheat... >> >> This way your weld overlay will be thicker than 3 mm and you should >> weld a PQR coupon to make sure you have 3mm of 410 weld layer "over" >> the buffer layer. Maybe you'll have to deposit one buffer (309L or >> 310L) and 2 layers of 410S. Try using Pulsed GMAW to get the results >> with depositing one layer. >> >> One of our colleagues have successfully deposited one layer of 410 >> weld overlay on A516 using Pulsed-MIG (Preheat is essential). It's >> because Pulsed-MIG has less dilution and you may achieve required >> results in one layer. >> >> For PQR, you need 4 side bend tests, chemical analysis on the surface >> of overlay and 3-4mm below the surface, and hardness test (on the > surface). >> >> Discuss these issues with your client before proceeding. >> Good Luck >> *Ramin Kondori* >> *Sr. QA/QC Engineer >> * >> *SINOPEC* >> >> r.kondori@petroyada.com >> +98-2123592322 >> +98-9132150320 >> >> >> On Mon, May 27, 2013 at 4:37 PM, Branko Ferencak <bran2605@gmail.com> >> wrote: >> >>> I have shell 20mm thick ( SA-516 Gr, 60 ) and there must be cladd >>> AISI 410S 3mm Could anybody tell me which filler i can use, for SAW >>> and GMAW? >>> GMAW i  planning use for flanges and tubesheets ( after i overlay >>> tubesheet - what is procedure for welding tube to tubesheet? ) Also >>> PWHT has been asked by customer after overlay. >>> Can anybody tell the effect of PWHT on SS 410S overlay? >>> What will be the the safe range of temperature of PWHT?  ( Also >>> recommended temperatures and times, holding cooling...) >>> >>> Best regards, >>> Branko Ferencak >>> >>>  -- >>> To post to this group, send email to >>> materials-welding@googlegroups.com >>> To unsubscribe from this group, send email to >>> materials-welding+unsubscribe@googlegroups.com >>> For more options, visit this group's bolg at >>> http://materials-welding.blogspot.com/ >>> >>> http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=1227 >>> 87&trk=anet_ug_hm >>> >>> The views expressed/exchnaged in this group are members personel >>> views and meant for educational purposes only, Users must take their >>> own decisions w.r.t. applicable code/standard/contract documents. >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "Materials & Welding" group. >>> To unsubscribe from this group and stop receiving emails from it, >>> send an email to materials-welding+unsubscribe@googlegroups.com. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >>> >>> >> >> -- >> To post to this group, send email to >> materials-welding@googlegroups.com >> To unsubscribe from this group, send email to >> materials-welding+unsubscribe@googlegroups.com >> For more options, visit this group's bolg at >> http://materials-welding.blogspot.com/ >> http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=12278 >> 7&trk=anet_ug_hm >> >> The views expressed/exchnaged in this group are members personel views >> and meant for educational purposes only, Users must take their own >> decisions w.r.t. applicable code/standard/contract documents. >> --- >> You received this message because you are subscribed to the Google >> Groups "Materials & Welding" group. >> To unsubscribe from this group and stop receiving emails from it, send >> an email to materials-welding+unsubscribe@googlegroups.com. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> > > -- > To post to this group, send email to materials-welding@googlegroups.com > To unsubscribe from this group, send email to > materials-welding+unsubscribe@googlegroups.com > For more options, visit this group's bolg at > http://materials-welding.blogspot.com/ > http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk= > anet_ug_hm > > The views expressed/exchnaged in this group are members personel views and > meant for educational purposes only, Users must take their own decisions > w.r.t. applicable code/standard/contract documents. > --- > You received this message because you are subscribed to the Google Groups > "Materials & Welding" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to materials-welding+unsubscribe@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- > To post to this group, send email to materials-welding@googlegroups.com > To unsubscribe from this group, send email to > materials-welding+unsubscribe@googlegroups.com > For more options, visit this group's bolg at > http://materials-welding.blogspot.com/ > http://www.linkedin.com/groups/MaterialsWelding-122787?home=&gid=122787&trk=anet_ug_hm > > The views expressed/exchnaged in this group are members personel views and > meant for educational purposes only, Users must take their own decisions > w.r.t. applicable code/standard/contract documents. > --- > You received this message because you are subscribed to the Google Groups > "Materials & Welding" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to materials-welding+unsubscribe@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- *Ramin Kondori* *Sr. QA/QC Engineer * *SINOPEC* r.kondori@petroyada.com +98-2123592322 +98-9132150320 -- To post to this group, send email to materials-welding@googlegroups.com To unsubscribe from this group, send email to 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Re: [MW:17852] SAW FLUX REUSAGE.

Dear Manoj,
Pls refer AWS D1.1 Cls 5.3.3.3, it is clearly
mentioned that you can use the mixture of used flux and virgin flux
but it does not affect the composition of the flux materials.

Thanks & Regards,
Bala

On 5/29/13, manoj john <manojacgnr@gmail.com> wrote:
> Dear Memebers,
>
> We are using SAW process for Carbon Steel welding but i have doubt in reuse
> of flux . My doubt is that on what basis we can reuse the electrode i am
> not able to find any standard or guide line for reusing. We are reusing
> the fluxes mixed with 20% used and 80% new flux, is it OK and please give
> me some information for reusing of flux or mixing of used flux with new
> flux.
>
> Thanks in advance.
>
> Manoj
>
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Re: [MW:17848] Regarding baking of low hydrogen electrodes

After  breaking the seal and considerable gap of time, re-baking is to be done for LH type electrodes,

as the electrodes would have picked up moisture by then  when exposed to the humid conditions. 

 

All low Hydrogen type electrodes may have > 10 ml  & < 15 ml of H2 per 100 grams of weld (except for

H4 type LH  electrodes, where it is less than 3 to 4 ml. of H2 ) and re drying  to be done  to reduce the H2 level   to < 10 ml.by holding them at 300 deg. C for 2 hrs. in the oven. 

Drying should be done only once and prolonged drying  (or) more drying cycles will whither the flux

coating and may produce cracks  on the coating surface and make the electrodes unusable.

 

The electrodes are then held in Holding oven (if required) at 100-150 deg.C,  if backed in large quantity

and to avoid repeated re-baking (re-cycling) and damage to the coating if  unused for any prolonged

period like unforeseen circumstances, holidays etc

Welders are supposed to use portable (kept at 100 deg. C or so) for actual welding. These ovens also know as re-fill ovens as the electrodes are re-filled after  every 2 hrs. of welding work or less. 

 

Sridhar.

 

 

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From: shashi <slpo1980@gmail.com>
To: materials-welding@googlegroups.com
Sent: Friday, 31 May 2013 11:44 AM
Subject: [MW:17843] Regarding baking of low hydrogen electrodes

Dear experts,

                        I have query regarding baking of low hydrogen electrode, is there any universal rule/standard governing these as in some project rebaking is not allowed whereas in some project re-baking can be done only 1 or 2 times.

Query1: how many time can we bake the low hydrogen electrodes, if over baked what will be the consequence.

 

Query2: after baking we transferred to holding oven maintain at 150 ° C,  how long we will keep electrodes at these temperature

Regards

shashi

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