About insulating stainless steel...

[keclose]

Have you seen this kind of failure before if you do not follow the instruction below?
Kerem.

"All austenitic stainless steel surfaces proposed to be insulated and having temperature above 50C shall be suitably protected by wrapping with aluminium foil 0.1mm thick or painted with suitable anti-corrosive paint before application of insulation as protection against chlorides in insulating materials and stress corrosion cracking."

 

[arto]

For insulating stainless, you want insulation per ASTM C-795
"Standard Specification for Thermal Insulation for Use in Contact with Austenitic Stainless Steel" with Low leachable Chlorides.

 

[EdStainless]

Yes, under insulation corrosion is a big deal. It has caused failures in a lot of pipe and tubing. There are special NDT methods to try and detect UIC.
There are two parts to prevention. First is low choride insulation. Second is making sure that no corrosive agents can enter the insulation. If these lines are out doors then you should use epoxy coated piping. The insualtion must be covered with weather shields. And make sure that there are drain holes in the bottom side.

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Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[keclose]

Thanks...
Can you give me popular examples for low chloride insulations?
Kerem.

 

[EdStainless]

You need to buy a copy of C795. I don't have one, but it will tell you how to specify these materials.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[arto]

do a google there's a bunch (you'll have to narrow it down by your other requirements):

http://www.knaufusa.com/products/co...t_insulation/knauf_1000°_pipe_insulation.aspx

http://www.owenscorning.com/comminsul/products.asp?product=258

http://www.owenscorning.com/comminsul/documents/Guide Spec VaporWick.doc

http://www.brantonindustries.com/industrl.html

http://www.valueng.com/proshield.html

http://www.roxul.com.my/graphics/RX-MY/pdf/Rockpipe C11_R1.pdf

 

[swall]

I have used polyethylene shrink tubing on braided ss hydraulic hose where the customer wanted to put a foam noise deadening sheath over the hose. This was an automotive underhood application. We did EDS analysis of the shrink wrap to verify no chlorine.

 

[JamesCKelly]

You might consider the lean duplex stainless LDX 2101, nominal about 21Cr 1.5Ni 5Mn. Almost twice the strength of 316L, better corrosion resistance than 304L. Roughly comparable to 316L in corrosion resistance. Resists the SCC which happens under insulation. Weldable. Available, at least in flat rolled. Res

 

[strider6]

CUI - corrosion under insulation is a serious issue, expecially if you are in an offshore plant or near the sea where you can have chloride from atmosphere. You can have pitting and CSCC for SS in a range of temp beetwen 50-160°C operating temperature.
I suggest you to look at NACE RP 0198-2004 "The control of Corrosion under thermal insulation and Fireproofing Materials -As Systems Approach", you will find all the information you need regarding this issue. Also look at

http://www.hse.gov.uk/offshore/corrosion.pdf.

Hope this help

regards
Vitt

http://www.corrosionist.com