Materials & Welding

Dear Sir, Can anyone advice how much spacing( code reference)  required for thermocouple installation in oil fired Tank PWHT  and burner position inside tank. Regards, Ranajit Chatterjee -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/1768823305.S.589.13700.f5mail-224-226.rediffmail.com.1768823516.2345%40webmail.rediffmail.com .

Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CANV5n6iM1bqGdmtzFU4C6dsJZiNnOFpT%3DM3KUq-P1UA%2B1CS7yQ%40mail.gmail.com .

No such relationship I read. Thanks  Sent from my iPhone On 19 Jan 2026, at 6:50 PM, Mahmood Alhinai <mahmood.m.alhinai@gmail.com> wrote:  Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CANV5n6iM1bqGdmtzFU4C6dsJZiNnOFpT%3DM3KUq-P1UA%2B1CS7yQ%40mail.gmail.com .

Hydrogen cracking will take time like 24 to 48hr. So generally after welding 1 or 2days gap is preferable for hydro test. On Tue, 20 Jan 2026, 7:39 am 'rehan khan' via Materials & Welding, < materials-welding@googlegroups.com > wrote: No such relationship I read. Thanks  Sent from my iPhone On 19 Jan 2026, at 6:50 PM, Mahmood Alhinai < mahmood.m.alhinai@gmail.com > wrote:  Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CANV5n6iM1bqGdmtzFU4C6dsJZiNnOFpT%3DM3KUq-P1UA%2B1C...

Hi     Immediately you can do hydro if no NDT coverage Thanks Regards  S.Indirajith On Mon, 19 Jan 2026 at 11:50 PM, Mahmood Alhinai < mahmood.m.alhinai@gmail.com > wrote: Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CANV5n6iM1bqGdmtzFU4C6dsJZiNnOFpT%3DM3KUq-P1UA%2B1CS7yQ%40mail.gmail.com . -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- You received this message because you are subscribed to the Google Groups "Materials &...

  Once the welded joint has cooled and radiographic testing (RT) is accepted, hydrotesting may proceed. Except in cases involving special alloys or stress relieving (SR), a waiting period is required."   On Mon, Jan 19, 2026 at 9:19 PM Mahmood Alhinai < mahmood.m.alhinai@gmail.com > wrote: Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CANV5n6iM1bqGdmtzFU4C6dsJZiNnOFpT%3DM3KUq-P1UA%2B1CS7yQ%40mail.gmail.com . -- https://materials-welding.blogspot.com/ https://www.linked...

There is no time limit after completion of welding and hydrotest. Normally after welding the pressure joints, you need to perform NDT and some code specify the time limits between welding completion & NDT& also you perform structural attachments etc.. Thanks & Regards J.Gerald Jayakumar 0091-8838619635 On Monday, 19 January 2026 at 09:19:55 pm IST, Mahmood Alhinai <mahmood.m.alhinai@gmail.com> wrote: Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- You received this message because you are subscribed to the Google Groups "Materials & Welding" group. To unsubscribe from t...

The minimum time limit between welding completion and hydro-test is not fixed and ultimately depends upon the specific service content, material type, and the relevant code requirements. These factors dictate the need for any delays for processes like cooling, NDT, or stress relieving before the hydro-test can proceed. On Tue, Jan 20, 2026 at 2:03 PM 'james gerald' via Materials & Welding < materials-welding@googlegroups.com > wrote: There is no time limit after completion of welding and hydrotest. Normally after welding the pressure joints, you need to perform NDT and some code specify the time limits between welding completion & NDT& also you perform structural attachments etc.. Thanks & Regards J.Gerald Jayakumar 0091-8838619635 On Monday, 19 January 2026 at 09:19:55 pm IST, Mahmood Alhinai < mahmood.m.alhinai@gmail.com > wrote: ...

Hi, Hydrostatic test should be preferred only after the risk period for HICC has reasonably passed and all inspections are accepted. Recommended practice (clear answer) ✅ For Carbon Steel / Low-Alloy Steel Minimum waiting time: 48 hours after completion of welding Best practice (critical joints / thick sections): 72 hours Hydrotest only after: All welding completed PWHT completed (if applicable) VT + required NDT (MT/PT/UT/RT) completed and accepted Delayed MT/PT after 48–72 hrs shows no cracks 👉 Then proceed with hydrotest Regards, MJ On Mon, 19 Jan, 2026, 6:50 pm Mahmood Alhinai, < mahmood.m.alhinai@gmail.com > wrote: Dear expert, Kindly what is minimum time limit between completion of welding and the hydrotest? Thanks Mahmood -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- You received this message because you are subscribed to the Google Groups "Materials & Welding" group. To unsubscribe from this group an...

Whether aluminium foil is to be installed before applying the insulation materials on stainless steel pipe/equipment surface? -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CAFnHyONVAKDb9pqjJ_u8io1WHmzWY5ee8Bm4bmCXoXUaGKANGQ%40mail.gmail.com .

Yes,this is to prevent corrosion of the SS surface by chlorides present in insulation material as the aluminium works as sacrificial material. On Thu, Jan 22, 2026 at 10:37 PM Sanga Girivardhana Reddy < girisanga@gmail.com > wrote: Whether aluminium foil is to be installed before applying the insulation materials on stainless steel pipe/equipment surface? -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CAFnHyONVAKDb9pqjJ_u8io1WHmzWY5ee8Bm4bmCXoXUaGKANGQ%40mail.gmail.com . -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- You received this messag...

Why Aluminium Foil Is Avoided on SS: Risk of galvanic corrosion Traps moisture → increases CUI risk Not recommended by most standards (e.g., NACE SP0198, ASTM, refinery practices) Recommended Good Practice: Clean SS surface Apply approved primer or barrier coating if specified Install insulation Apply aluminium cladding as outer weather protection Follow project specification and service conditions With Regards Anish R Kurup On Fri, 23 Jan, 2026, 6:43 pm nandakumar pandit, < panditns1@gmail.com > wrote: Yes,this is to prevent corrosion of the SS surface by chlorides present in insulation material as the aluminium works as sacrificial material. On Thu, Jan 22, 2026 at 10:37 PM Sanga Girivardhana Reddy < girisanga@gmail.com > wrote: Whether aluminium foil is to be installed before applying the insulation materials on stainless steel pipe/equipment surface? -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- You received this m...

Dear experts greetings  1. Why this question is important (Stainless Steel + Insulation) Stainless steel equipment and piping are highly susceptible to: Chloride Stress Corrosion Cracking (CSCC) Crevice corrosion Corrosion Under Insulation (CUI) Direct contact of aluminium foil or wet insulation with stainless steel can trap moisture and chlorides, leading to premature failure. 2. Correct Insulation Layer Arrangement (Standard Practice) Typical Correct Layer Sequence Stainless steel surface Surface preparation + protective coating / corrosion barrier Insulation material Aluminium foil / aluminium cladding (weather & mechanical protection) 3. Is aluminium foil installed before insulation? General Answer: NO Aluminium Foil Allowed? Reason Directly on SS pipe Not recommended Risk of moisture trapping & CSCC As insulation facing (factory laminated)  Yes (with conditions) Acts as vapor barrier Over insulation (outer jacketing) Yes Weather & mechanical protection Removable insula...

Dear Experts,   I have a question related to Clause NB-4335.1 & NB-4335.2 from ASME Sec III Subsection NB.   NB-4335.1 Impact Tests of Weld Metal. (a) Impact tests of the weld metal shall be required for welding procedure qualification tests for production weld joints exceeding 5∕8 in. (16 mm) in thickness when the weld will be made on the surface or penetrate base material that requires impact testing in accordance with NB-2310.   NB-4335.2 Impact Tests of Heat-Affected Zone. (a) Charpy V-notch tests of the heat-affected zone of the welding procedure qualification test assembly are required whenever the thickness of the weld exceeds 5∕8 in. (16 mm) and either of the base materials require impact testing in accordance with the rules of NB-2310.   *I want to know your opinion if the above clauses are applicable to fillet welds.   Also to note that Clause NB-4622.3 (Definition of Nomi...

Greetings, Need expert opinion for the following query: Construction Code ASME B31.3, Qualification ASME BPV Sec. IX. One of the WPS is qualified for Low temperature Carbon steel with impact testing and PWHT. The qualification range is 20mm to 36mm.  PWHT is applicable (Project specification). Soaking time was 1 hr 30 minutes. Question: Is this WPS qualified for a repair weld with this soaking time?  Is a new PQR to qualify the repair joint? Best Regards, Muhammad Babur Khan Lashari Project Quality Supervisor. API 570, API 510, CSWIP 3.2.2. ISO 9001:2015 Mob: +966 58 2774568 / +966 51 0559680 Please consider the environment before printing this e-mail -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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@google...

Greetings  Yes — only if the repair weld falls entirely within the qualified range and the PWHT performed meets the same essential variables as originally qualified. If any variable in the repair (thickness, PWHT hold time, PWHT temperature, base material, filler metal, joint design) exceeds the qualified range, then the existing WPS cannot be used and a new PQR is required. Best regards On Wed, Jan 28, 2026, 7:49 AM Babur Khan < mbabur.bwp@gmail.com > wrote: Greetings, Need expert opinion for the following query: Construction Code ASME B31.3, Qualification ASME BPV Sec. IX. One of the WPS is qualified for Low temperature Carbon steel with impact testing and PWHT. The qualification range is 20mm to 36mm.  PWHT is applicable (Project specification). Soaking time was 1 hr 30 minutes. Question: Is this WPS qualified for a repair weld with this soaking time?  Is a new PQR to qualify the repair joint? Best Regards, Muhammad Babur Khan Lashari Project Quality Supervisor. API 570, API 5...

Dear  New PQR need to be qualified for the repair welding as per the client requirements. Thanks & Regards, Ananth Karuppanan. Mobile : +91-9597936444                +971-588925593 On Wed, 28 Jan 2026 at 7:49 AM, Babur Khan < mbabur.bwp@gmail.com > wrote: Greetings, Need expert opinion for the following query: Construction Code ASME B31.3, Qualification ASME BPV Sec. IX. One of the WPS is qualified for Low temperature Carbon steel with impact testing and PWHT. The qualification range is 20mm to 36mm.  PWHT is applicable (Project specification). Soaking time was 1 hr 30 minutes. Question: Is this WPS qualified for a repair weld with this soaking time?  Is a new PQR to qualify the repair joint? Best Regards, Muhammad Babur Khan Lashari Project Quality Supervisor. API 570, API 510, CSWIP 3.2.2. ISO 9001:2015 Mob: +966 58 2774568 / +966 51 0559680 Please consider the environment before printing this e-mail -- https://materials-welding.blogspot.com/ https://www.linkedi...

The qualification range would be 16 to 36mm if you qualify a PQR On 18mm plate thickness, PWHT soaking on pqr is 1hr 30mins so maximum soaking with impact will be 1hr 52.5hrs, if you are doing the resoaking and if the total soaking time ( Actual PWHT & Repair PWHT soaking time) is within this range you can use this, if it exceeded need to requalify. The above explanation is based on With impact testing below the Lower transformation temperature (AC3) On Wed, 28 Jan 2026, 6:19 am Babur Khan, < mbabur.bwp@gmail.com > wrote: Greetings, Need expert opinion for the following query: Construction Code ASME B31.3, Qualification ASME BPV Sec. IX. One of the WPS is qualified for Low temperature Carbon steel with impact testing and PWHT. The qualification range is 20mm to 36mm.  PWHT is applicable (Project specification). Soaking time was 1 hr 30 minutes. Question: Is this WPS qualified for a repair weld with this soaking time?  Is a new PQR to qualify the repair joint? Best Regards, Mu...

If new PQR qualification as per client specification is there means no need to ask this question, normal & repair PQR should be qualified separately. If we are talking on the basis of ASME SEC 9 & ASME B31. 3, below Explanation is sufficient. The qualification range would be 16 to 36mm if you qualify a PQR On 18mm plate thickness, PWHT soaking on pqr is 1hr 30mins so maximum soaking with impact will be 1hr 52.5mins, if you are doing the resoaking and if the total soaking time ( Actual PWHT & Repair PWHT soaking time) is within this range you can use this, if it exceeded need to requalify. The above explanation is based on With impact testing & PWHT below the Lower transformation temperature (AC3) On Wed, 28 Jan 2026, 6:49 am ananth karuppanan, < ananthkaruppanan91@gmail.com > wrote: Dear  New PQR need to be qualified for the repair welding as per the client requirements. Thanks & Regards, Ananth Karuppanan. Mobile : +91-9597936444                +971-588925593...

See snap shot below from ASME B31.3. No Repair procedure is required. But PWHT has to be performed after Repair. PWHT soaking time should have been added during the original PQR Qualification or Simulated test coupon including Repair soak time shall be included during Material testing. Thanks & Regards J.Gerald Jayakumar 0091-8838619635 On Wednesday, 28 January 2026 at 07:48:56 am IST, Babur Khan <mbabur.bwp@gmail.com> wrote: Greetings, Need expert opinion for the following query: Construction Code ASME B31.3, Qualification ASME BPV Sec. IX. One of the WPS is qualified for Low temperature Carbon steel with impact testing and PWHT. The qualification range is 20mm to 36mm.  PWHT is applicable (Project specification). Soaking tim...

Greetings, Thank you for your kind response. In pur PQR, soaking time for repairs Welding not considered.  Muhammad Babur Khan Sent from my iPhone On 28 Jan 2026, at 8:48 AM, 'james gerald' via Materials & Welding <materials-welding@googlegroups.com> wrote:  See snap shot below from ASME B31.3. No Repair procedure is required. But PWHT has to be performed after Repair. PWHT soaking time should have been added during the original PQR Qualification or Simulated test coupon including Repair soak time shall be included during Material testing. <1769579047580blob.jpg> Thanks & Regards J.Gerald Jayakumar 0091-8838619635 On Wednesday, 28 January 2026 at 07:48:56 am IST, Babur Khan <mbabur.bwp@gmail.com> wrote: Greetings, Need expert opin...

Dear expert,  As per the project requirements we ASME SA 333 GR 6 ED-2023 pipe and Acceptable ASTM ED-2011 through 2016. But we received pipe is ASTM ED-2018.  Can you please share the recertification format for SA 333 GR  6 pipe. Is ther any other option to accept this pipe? Thanks Jijo George  -- https://materials-welding.blogspot.com/ https://www.linkedin.com/groups/122787 --- 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 . To view this discussion visit https://groups.google.com/d/msgid/materials-welding/e4da61d8-85a3-45a5-9f8f-025dce4a1ecfn%40googlegroups.com .

For NACE service can we do RT/UT before PWHT ? Regards, Ranajit Chatterjee From: dvreddy82@gmail.com Sent: Mon, 29 Dec 2025 13:39:28 To: materials-welding@googlegroups.com Subject: Re: [MW:35934] RT/UT before PWHT for P1 material   Hi, For H2 service you have to NDT RT/UT after PWHT. Better to do hardens also.           On Mon, 29 Dec 2025, 10:39 am 'ranajit chatterjee' via Materials & Welding, <materials-welding@googlegroups.com> wrote: Dear Sirs, As per ASME B31.3 clause no.341.3.1(a) mentioned P Nos.3,4,5A,5B,5C AND 15 materials examination(RT/UT) shall be performed after completion of heat treatment. But no information for P1 material whether NDT performed before or after PWHT. Please advise can we perform NDT(RT/UT) before PWHT activity for P1(NACE/H2 service) material or not. Regards, Ranajit Chatterjee 9995018265   -- https://materials-welding.blogspot.com/...