Materials & Welding

Hi respected group members, Pl share some experience on weld overlay on F6Nm material? Regards,  Sent from Yahoo Mail for iPhone On Friday, May 8, 2026, 7:15 PM, sridhar cn <sridharcn305@gmail.com> wrote: From the available Technical literatures. CS. On Fri, 8 May 2026 at 09:58, Kannayeram Gnanapandithan < kgpandithan@gmail.com > wrote: could pl  share the reference where it is given THANKS & BEST REGARDS, KG.PANDITHAN, BE, IWE,   ISO ...

Dear experts Good morning, Is there any minimum weld length for RT in the WQT on AWS D1.1 qualification? I checked there criteria specified in AWS D1.1 6.23.3.1 exclude 32 mm at each end of the plate. BELOW Source AWS D1.1 6.23.3 RT.  If RT is used in lieu of the prescribed bend tests, the weld reinforcement need not to be ground or otherwise smoothed for inspection unless its surface irregularities or juncture with the base metal would cause objectionable weld discontinuities to be obscured in the radiograph. If the backing is removed for RT, the root shall be ground flush (see 7.23.3.1) with the base metal. 6.23.3.1  RT Test Procedure and Technique. The RT procedure and technique shall be in conformance with the requirements of Clause 8, Part E and Clause 10, Part F for tubulars. F or welder qualification, exclude 1-1/4 in [32 mm] at each end of the weld from evaluation in the plate test; for welding operator qualification exclude 3...

  Though I have not done actual overlay, what I could gather from the available literature is that,  F6NM Stainless Steel weld overlay is   commonly   done in hydro turbine parts, valve internals,  and  pump sleeves   . The success of overlay depends much  more on dilution  control,   hydrogen control, and post-weld hardness management than on the actual deposition process itself.  F6NM / CA6NM  is  a  P6, air hardening l ow carbon martensitic stainless steel  with a pprox. 13% Cr + 4% Ni +  1%  Mo . Its UTS is 750-950 MPa,                                    Yield  550-750 MPa, 15-22% EL and hardness 259-320 HB.  Major issue s  observed  during overlay are :   Underbead cracking ; d elayed hyd...

could pl  share the reference where it is given THANKS & BEST REGARDS, KG.PANDITHAN, BE, IWE,   ISO 9712 Level 2 in VT, ASNT-Level II in PT,MT,RT & UT, LA ISO 9001-2015, ISO 3834, EN 1090 & EN 15085,  International Welding Engineer.  CONSULTANT-WELDING & QUALITY Mobile no: +919940739349 On Mon, May 4, 2026 at 3:18 PM Ashishranjan - Domech Fabricators Pvt.Ltd. < planningdfplril@gmail.com > wrot...

Dear Mr. Sankaran, Thanks for the reply and your understanding. rgds, Sridhar. On Mon, 4 May 2026 at 15:18, Ashishranjan - Domech Fabricators Pvt.Ltd. < planningdfplril@gmail.com > wrote: Yes, you can use multiple PQRs to support a single WPS under AWS as well  but it’s handled a bit differently than in ASME Section IX, and you need to be careful about how you justify it.    Regards, Ashish Ranjan +91 9555864374 Save a tree...Please consider your environmental responsibility. Before printing this e-mail message, ask yourself whether you really need a hardc opy. " Confidentiality Warning : This message and any attachments are intended only for the use of the intended recipient(s), are confidential and may be privileged. If you are not the intended recipient, you are hereby notified that any review, re-transmission, conversion to hard co...

What the Macro Suggests From the image: Fusion is occurring on the upper groove walls. Root area shows an unfused triangular gap / cold lap zone . Weld metal is flowing around the joint rather than penetrating fully to the root. This is typical when the arc cannot adequately reach the root face or root land. Likely Causes 1. Amperage Too Low for Root Pass 82 A for first pass on a restrained joint with 50 mm thick tubesheet may be too low, especially if heat is rapidly absorbed by the heavy SA-516 tubesheet. The tubesheet acts as a heat sink , pulling heat away from the root. 2. Groove Design / Root Land Too Heavy If the groove has: narrow included angle excessive land/root face insufficient tube projection or mismatch then penetration becomes difficult at lower amps. 3. Arc Position / Torch Angle If arc is focused too much on filler or upper bevel edges rather than root corner, fusion at the bottom will be poor. 4. Travel Speed Too F...