Coating System

The reader will be looking for the names, nature, composition, pressure and temperature of the fluids likely to be in contact with it, the material used for the tank structure, its method of support, its method of construction, etc., in order to help with this post. CONTEXT please! One sentence is never enough.

Tank is made of steel 37, pressure 5 - 6 bar, max 150 degrees C

That's about the info I have now

And the fluids?

Just water. Thanks

Corrosion data for water should be available in any Chem Eng textbook.

NAPA, you need to specify : demin water, deionized water, tap water... deionized and demin water are tough on paint system... choosing the wrong paint system you will end up with huge delamination short term...

PW is right : before making any recommandation you have to answers these questions:

Location of the tank? Inside or outside, isolated or not. Can the tank be force cure or baked? Is there any vapor going back to the tank? Are you using any chemical (concentration please) to treat your water?

Is this a new tank?? If a used tank have you done decontamination? what was the product involved? describe previous service? How surfaces currently protected?

Job site: any unusual jobsite condition? Thermal shock or cycle? Need FDA NSF or any other compliance? Physical factors: abrasion, impact, pressure, velocity, cathodic protection, etc..

Surface preparation must an SSPC-SP10 minimum and probably an SSPC-SP5... can you perform it if we recommend a profile of 4to5 mils for example.

The service describe is really tough for a paint system and making the wrong recommandation will cost you money and lot of frustration. It not as simple as it looks sometimes...

Napa:

Is the steel 37 materials is recommended by ASME as reference for High Temp Steel Materials for pressure vessel?

150deg C is in the range of Hot Water Boiler Parameters. Are you heating the water on this vessel upto 150deg C?

I dont think a reasonable coating for 150deg C is availlable in the market in terms of cost effective application. Unless you may have to use SS316 Materials. in ASME recommendations you may need to use ASTM A516 Gr.70. Provided your water should deaerated to remove the oxygen. at high temp, TDS is likely to be monitored as this will cause a problem.

Kindly elaborate more about the process. perhaps we can recommend something better materials.

jojie_oak

Hi,

In relation to specifying coating systems much of the knowledge is located at manufacturers and suppliers. However it is crucial as mentioned in above threads to identify the metal-coat-fluid interaction and compatibility. Youneed to apply a coat that is compatible with the metal substrate in order to assure adequate adhesion depending on the type of the coat of course. Also a crucial factor here is your budget and the level of protection required in relation to the life service of the structure. Cathodic protection systems in terms of sacrificial anodes, galvanizing, galvanizing+top coats, corrosion inhibitors in relation to teh latter; all are applied successfully to tanks and each carries its own features in relation to corrosion control and prevention and the service. I would advise to check the chemistry of the water to be stored and identify the level aggresive anions that are present in water. This will give you an indication as a started to the level of protection needed combined with factors in relation to abrasion, temperature, and all factors mentioned in above threads. A second step is to identify the type of coating system in oder to achieve this level of protection. You need to search websites and contact suppliers in order to gain such practical knowledge according to their experience in this field from previous projects. You can also find lots of information in their websites and data shets for performance of coats in relation to different environments. Another good source is NACE publications in relation to coating systems. Check their website and am sure you will find lots of stuff there to increase the level of your knowledge in such a domain.

Hope the above helps,

cheers,

150 C is very hot, and if you want to contact us at www.unconventionalsolutions.biz we can tell you what if anything will work. Doug

maybe u can use PTFE..is like frying pan>> non sticking pan... i guess

There are plenty of coatings for this environment, but I would recommend you stay away from solvented coatings (they will have inherent problems with solvent entrapment - voids, and internal stress - cracking).

A 100% solids epoxy should do.

Belzona offers a complete line of coatings for all types of services, but I assure you that the price of the materials can be dear.

To be fair, the costs for surface prep., and application will be just as dear, and when you apply this sort of solution the surface prep is just as important as the material selection.

I believe they have distributors all over the world, so just call them up and ask for your local distributor. They'll come take a look at your issue and sort it out for you.

Good luck!