Skip to main content

Re: [MW:32347] Sulfuric acid drum nozzle problem

Dear zohair,

Thank you for your help! We have decided to use SS316 steel instead of carbon steel. Problem is actually because of sulphuric acid corrosion.

Kind regards,

1 Nisan 2021 Perşembe tarihinde saat 09:51:58 UTC+3 itibarıyla Zohair.O şunları yazdı:
Hi everyone, 

Sulfuric acid is very tricky when we talk about corrosivity because it depends on many factors ( concentration, temperature, velocity ... etc). For the concentration of 98% generally, it's better to use the SS316 instead of carbon steel for pipes, and you may use the carbon steel tanks with SS clad or overlaid nozzles. 
I thank the problem is mainly related to material selection.    
you can consult the NACE Standard related to sulfuric acid storage tank inspection. 

Z.O
Le mercredi 31 mars 2021 Ć  04:14:02 UTC+1, chandrakant mohikar a Ć©crit :
Nozzle failed means, what exactly happened.?  if no flow through nozzle means, it is choked. it should be dechoked and material like dirt etc to be removed, another reason may be there is some other corrosive material through reverse flow. you can conduct systematically risk / HAZOP study with guidewords. if you can isolate, drain 99% H2SO4, remove nozzle and perfoem QA / TIC (testing, inspection & certification). as per design & EPC requirements, considerations & criteria. 

chandrakant mohikar


  

On Tue, 30 Mar 2021, 14:01 okay Tutar, <okay...@gmail.com> wrote:
Hello everyone, I hope you all have a nıce day.

We had a problem in sulfuric acid %99 conct. drum nozzle.

After 2 years of operation, suddenly our nozzle has been failured.
We checked api 571.Concentration of acid is ok, it is %99.Speed of acid is lower than critical level.
But, when we examine flange and piping of nozzle. There is general corrosion and thickness of weld neck is thinned . Our material is carbon steel. But, in pipe thickness is not thinned.
Do you have suggestion for reason of this problem ? What could it be ?

--
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-weld...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/d4b67686-33e7-429b-9ebc-9e16768ddb8cn%40googlegroups.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 & 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 on the web visit https://groups.google.com/d/msgid/materials-welding/0fe8eb69-2c30-49af-b0fa-8b4f982677b3n%40googlegroups.com.

Comments

Popular posts from this blog

Re: [MW:10788] ON PLOT PIPING & OFF PLOT PIPING

Piping systems involved for the flow lines and gathering lines from the well head isolation valve to the production facility or processing plant isolation valve are determined as OFF PLOT. ON PLOT defines piping system in the processing plant and production platform. ANSI/ASME B31.4 applies for off plot piping system. B31.4 allows the use of either API 1104 or ASME section IX (as appropriate). However, occasionally, a very small system such as piping within 500 feet of a processing plant (some client also said 400 feet) may be declared B31.3 rather than B31.4. When B31.3 is invoked, only ASME Section IX is used. before you decide which code to use for welding procedure and/or welder qualification for pipe welding, you have to know the design and construction code applicable to the system. Please read far enough into scope and diagram illustrating the application of either B31.3 and B31.4 hope this helps rgds 2011/4/21 pradip kumar sil < pradipsil@gmail.com > Dear all, ...

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...