TRIM 10 or Trim 12 1

[ligin18]

Hi Experts
As per FEED material specification it’s mentioned that for ball valve “BALL 150# RF STL, RP, DI, FS, 316 TRIM”.I want to know is it Body “CS+ STL with trim 10” or Body “CS with Trim 12”

 

[Danlap]

Hi,
Can only imagine the abbreviation of STL is Stellite. Meaning for Metal to Metal (moving parts) only e.g. Ball and Seat.
the other "Trim" might be remain as plain 316 such as Spindle without Hard Facing.

Kindly note that your remarks and question is not really correspond. I don't see CS on “BALL 150# RF STL, RP, DI, FS, 316 TRIM”, so not really sure the answer is CS (body) + Trim 10 or SS (Body) with Trim 10? CMIIW

Regards,
MR

All valves will last for years, except the ones that were poorly manufactured; are still wrongly operated and or were wrongly selected

 

[gerhardl]

Hi ligin18,

Oh my! Again the branch language, made up by US specialists, trying to exclude the rest of the world , but sometimes effective in oral communication.

For the rest of the world the correct way is to send a mail to the originator: 'To avoid misunderstanding our QA system requires that all enquiries must be in full text with cross references to standards when applicable. Abbreviations to be avoided or explained. Please confirm with full text for abbreviations xxxxxxx, and updated (last issue) standard references for yyyyyyy.'

Regards
gerhardl

 

[ligin18]

Hi Danlap
The specification is for carbon steel.I miss to add that details.I want to know is it Body “CS+ STL" with trim 10 or Body “CS with Trim 12”.Different opinion from several people.One of our project vendor offer body as " CS+STL" with trim 10.I want to know "DI" means. Usually DI means ductile iron but its not match in this case.You mentioned Ball and seat STL. Is STL required for ball.
The service is produced water.The chloride content is around 143000 ppm and H2s is 1000 ppm.Is it possible to use SS trim for this much chloride content.Waiting for your reply.

 

[Danlap]

Hi Ligin18,

First of all I am not a metallurgist, abbreviation specialist nor Process Engineer.
My comment would be based on my first hand experiences only and for you to judge in respect with your own case.

Your service considered what as we call brine system, which is quite aggressive against Stainless Steel.
However in my current situation (I am in charge of several Plants) in similar brackish up to brine application, I do use:
-Carbon Steel piping with Alumunium Bronze / Ductile Iron / carbon steel valve with SS316 Ball and Soft Seat
-GRE piping with Flat Face Alumunium Bronze/ Ductile Iron with Al-Bronze trim
-SS piping with either SS valve or Super Duplex valve
There are several report that 316 (only) trim is prone for CSCC. But there is sometime also a no report at all (no report meaning acceptable function in many cases). And sometime it would be ridiculous to use Super Duplex valve for “water” from end user perspective (ones without solid engineering background)

In the past, I use to fabricate skid, vessel and pipeline under Swedish company using Swedish only valve e.g. AlfaLaval for similar application.
I’ve seen comparison between similar valve from Europe (which we tend to believe they check every detail chemical component of the base material) vs Non-Europe. And the Non-european valve fail miserably after 2-6 weeks in service.

Later I found out, that less stringent quality control of Stainless Steel fabricant/foundry do compromise Molybdenum and Nickel content of its product up to its lowest threshold. It is however still considered as Stainless Steel 316.

Since there have been and still is a constant surge of Non-European valve and complaint from end user, the paradigm is slightly shifted that 316 is not ok for brackish / brine application.
If I may summarize the safe level of using SS316 should be used for temperature below 20 deg C and below 120 g/L of Chloride (approx.. 120,000 ppm). Above this condition 316L is prone for CSCC

Shall carbon steel body is mandatory by the inquirer, suggest to make it with PTFE internal coating (also for using PTFE seat) and maybe 316 Ball with Stellite.

Again, better to ask the inquirer, whether they have good experience with the valve detail they have provide you. And ask them for the Long text in the future. If you are guessing, so do we. And what size and class is this valve anyway??

My excuse for all metallurgist shall my interpretation is incorrect.

Regards,
MR


All valves will last for years, except the ones that were poorly manufactured; are still wrongly operated and or were wrongly selected