We have a sour water stripper column 9mm thick on very top section and 18mm for the remaining section. The design corrosion allowance (CA) is 3mm.
Pits are mainly found on the 18mm thick section.
-Pits with depth about 1mm or less are spread across the shell for which plan is to use metal...
How can i check whether a tank is designed with release prevention barrier as per April 650 appendix I?
It has not been indicated specifically in any of the docs.
Nickypaliwal
Materials & Corrosion Engineer
Refer case as below for pressure vessel (design code is Sec VIII Div I - Section UCS-66):
- Required thickness of vessel - 9.5 mm
- Vendor offered A106 GrB SCH80 for shell so nominal thickness is 10.97mm
-Minimum Design Temperature - minus 29degC (-20degF)
As per the curve, A106 should fall...
we have a requirement for 18" and 20" ISO 3183 Gr L415, PSL2 (SMLS/LSAW/HFW) however the required length is very small so we want to use B31.3 material.
What major concerns related to material and material testing should be taken care other than mechanical testing requirements (tensile...
There is a 18" 10.3mm thick API 5L X65 HFW pipeline which passed all the tests including hydro test in mill however there is a pin hole leak observed near the seam weld which was observed in field hydrotest.
It was difficult to find the location of the leak as the leak is small and was not even...
Is there any difference between non-invasive and non-intrusive inspection?
If yes, then please provide an example or explanation of such a case.
As I understand, the meaning of both are same however the context in which they are used is a little different.
Non-intrusive is use to categorize...
What is the recommended material for the jet fuel piping and fasteners in airport supplies?
We have applied upstream standards and have proceeded with Stainless Steel piping and Low Alloy Steel bolts/nuts.
Is there any standard that calls for SS bolts/nuts?
Client is using SPW (SS316+Graphite) gasket for connecting galvanized CS flanges.
Although the service is instrument/utility air so temperature may not go high, I am doubtful about it.
is above combination acceptable?
What alternative do we have if the flanges are raised face and insulation...
Is there any limitation of coating type wrt to color?
As we use various coatings such as Aluminium pigmented silicone or Aliphtic Polyurethane etc, can we not get any desired color irrespective of coating type?
Please explain as how different colors (RAL No.) are achieved ?
Till what pressure have you experience a successful pneumatic test of threaded CS/galvanized CS piping ?
As per recent experience, we are facing issues with pneumatic testing of galvanized CS above 7barg. We need to actually test it at 16barg.
It starts leaking at threaded joints.
For low temperature design service (assuming -40degC), the vessel is proposed of LTCS.
In this case, do we need to propose support legs of LTCS if legs are holding the vessel ?
For lifting lugs, since they will not be used while vessel is online, can we use normal CS ?
Does mercury cause any corrosion to steels? API 571 only indicates LME to Copper, Aluminium and ALloy 400 from mercury.
Also some papers discuss about corrosion of SS316 from mercury and sodium amalgam.
Can we use ISO 15590-2/3 flanges and fittings inplace of F694 forgings and viceversa?
ISO looks more stringent compared to ASTM for pipeline forgings and fittings. Does it mean that most of the clients follow only ISO 15590 ?
Regards,
Nikhil
Generally valve material is selected based on process conditions. Assuming a fluid (without oxygen) and low corrosion rate however with very high chlorides.
If Carbon steel is selected for the body, can SS316 be used for trim for high chlorides?
As understood, the SCC only occurs when there...
I have mostly seen relief valves with non-wetted spring. However there are designs in which spring is wetted.
What is the basic difference in the usage (service wise eg Gas/liquid etc) or applicability wise? How do we know that which one has to be used?
I just wonder what are the other companies doing for small underground piping sections suchas road crossing. The client, I work for, use a visco-elastic material which is claimed to self heal and protect the surface even on coating damage. No CP is asked with this coating.
I have observed our client has used valves with CS body and Duplex SS/SDSS/Alloy 825 trim. Generally manufacturers may recommend DSS/SDSS/ALloy 825 etc grades for valve trim incase they need more strength or torque however from corrosion stand point, can it be justifies using such valves?
