Clean Room for fabrication of Heat Exchangers with Reactive Materials like Titanium

[DK44]

Dears
Understand that for Titanium Fabrication as for Heat Exchangers, a clean room (Dust free) is required at th Pressure Vessel workshop especially to warn off flying Iron particles in the air due to nearby metal Cutting / Grinding and other operation.
1. What are the norms for such enclosure especially with regard to cleanliness in terms of Microns.
2. Are there any Code guide lines for same Viz., ASME Sec VIII Div 1 / Div 2 or ASME Sec III.

 

[MJCronin]

Here is a place to start:

https://shopmetaltech.com/welding-technology/welding/titanium-welding-tips-to-succeed.html

You will find no information about titanium welding shop practices in ASME VIII

ASME Section III deals with Nuclear Power Grade Components.....

Are you, for the very first time, fabricating Titanium components for Nuclear Power Components ?

MJCronin
Sr. Process Engineer

 

[SnTMan]

DK44, on past projects, fabrication of surface condenser bundles, Ti tube-ts welding, the shop enclosed the tubesheet area with a fabricated a metal frame covered with plastic sheet and fitted with window-unit type A/C's.

Another project, fabrication of a large HX bundle where cleanliness was important (not Ti), the entire bundle was enclosed this way.

No standards involved, but served the purpose...

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[r6155]

See

https://www.eng-tips.com/viewthread.cfm?qid=220216

Regards

 

[EdStainless]

We had Ti tube mills inside an 'industrial clean room'. Not clean by 'clean room' standards but roughly class 1,000.
It was aluminum framed with plastic sheeting for roof and sides indie our plant. It had air filters and its own AC.
We kept dust to a minimum and humidity low, the alarms went off at 35 or 40% RH.
I have been in a number of fab shops building HX that used these temporary 'rooms' to protect clean work (SS or Ti) from the rest of the shop. Especially in high humidity regions.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[r6155]

Search "clean room" in

http://www.ashrae.org

Regards

 

[r6155]

I worked in the manufacture of pressure vessels for nuclear without a clean room. The key is to protect all materials (SS 347) to avoid iron contamination necessary to pass the ferroxyl test. Iron contamination is very difficult to remove.
I think a similar situation for Ti.

Regards

 

[DK44]

Dears.
Thank you for your valuable responses.
When a clean environment is required for the Fabrication (especially welding of Titanium metal parts-such as Heat Exchanger Titanium Tube to Tube Sheet welding and other attachments), there should be a certain limitation of Particle size say less than 5 Microns or so which requires a Clean room for such operations. What could be the recommended levels of cleanliness in such circumstances.

 

[r6155]

@ DK44
Have you already searched in ashrae.org? Don't you like to search?

Regards