Re: [MW:6142] Pressure Vessel Repair

Dear All,

Thank you for the valuable inputs.

I need some more clarifications. What kind of NDT required during and after repair work? Is vessel needs to be hydrotested after repair?

Thanks and Regards,

Limesh

On Tue, Jul 27, 2010 at 8:06 AM, tong tong <tong2je@gmail.com> wrote:

Dear Limesh,

I agreed with Sachin. Usually thickness of cladding is not considered to contribute either partially or fully to design thickness unless this thickness is included during min. thickness(design thickness) calculation for that vessel. Damaged/corroded shell plate may be repaired by removing a section and replacing it with an insert patch (flush patch). Please refer to NBIC-23, API 510 or ASME PCC 2 more details

Regards

On Mon, Jul 26, 2010 at 10:22 PM, sachin sankhe <sachin.sankhe@rediffmail.com> wrote:

Dear Limesh,

I understand that complete CS material is consumed due to corrosion and only cladded ss316 thk is remaining.
Usually thk of clad is not considered to contribute either partailly or fully to design thk requiremnent.
Clad portion thk is only from process point of view
So I would suggest patch work to be done in that area

Regards
Sachin
On Sun, 25 Jul 2010 13:34:44 +0530 wrote

>Dear All,

One of my friend need advise on the following issue,

We have a cladded vessel at our plant containing low pressure

corrosive service. While in operation the external shell of carbon

steel got corroded due to leakage from sight glass; total damaged area

is like 2 feet by 3 feet. Now the situation is that the cladded

material SS 316 is exposed. The thickness of cladded plate is barely

equal to the pressure design thickness. We want to seek advise on the

repair of the same. Should we go for the repair and if yes what should

be the procedure?

Thanks and Regards,

Limesh

--

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/

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.

--
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/
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.

--
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/
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.

--
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/
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.

Re: [MW:34105] SA266 GR4N 4 Cycle SPWHT

Hi, You are correct, Minimum refers to the one cycle for which this part will expose until final work shop PWHT. hence mill test certificate shall include this. Max. SPWHT, refers to additional cycles of heat treatment that are reserved for future repairs during equipment lifetime. Again, these simulated no. Of cycles shall be specified in MTC. The idea is we need to make sure that steel mechanical properties are not compromised upon exposure to multiple repairs (i e 4 cycles in your case). One could say, if steel is subjected to 4 cycles and is ok, then it should by defacto be good for one cycle, yet, this is wrong assumption cause mechanical problems and microstructure of materials varies accordingly based on no. Of cycles for which material will expose. This is apparent in alloy steel and especially for impact test values as an example. In your case, this forged CS with properties before PWHT can be understood to be " as forged" condition (i.e. Wit...

Materails FAQs

Q: What are equivalents for standard Q 235 B (and Q 235 A) for U-channels? (asked by: boris.vielhaber@vait.com) A: DIN Nr. = 2393 T.2, 2394 T.2, EN 10025 W. Nr. DIN 17007 = 1.0038 Design DIN 17006 = RSt 37-2, S235JRG2 (Fe 360 B) Q: What is St DIN 2391 BK material? (asked by: dmcandrews@automaticstamp.com) A: Precision steel tubes, cold-finished/hard. Q: What is C.D.W. Boiler Tube? (asked by: montydude123@yahoo.com) A: Cold Drawn Welded Boiler Tube. Q: WHAT IS W.Nr. 1.4301? PLS TELL US IN EASY LANGUAGUE (asked...

Heat tint (temper) colours on stainless steel surfaces heated in air // Heat tint

Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change. Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...

Materials & Welding

Search This Blog