High Pressure Corrosion resistant studs needed
High Pressure Corrosion resistant studs needed
(OP)
Hi Everyone.
I am currently building stainless steel pumps which are used in high pressure (up to 200 bar) applications and mounted on environments such as Oil platforms in the oceans. At current the main fasteners I am using are high tensile steel such as 12.9 grade. The pump is then painted with maritime paint usually to customer specifications. The problem is that the environment is getting through the paint and attacking the bolts and I fear is weakening these bolts. Can anybody recommend to me any grade of material for the bolts which give me better resistance to the environment but at the same maintain the tensile strength? I have thought of materials such as Inconel 718 but this is very expensive and I was hoping for some other suggestions?
Kind regards
Anthony
I am currently building stainless steel pumps which are used in high pressure (up to 200 bar) applications and mounted on environments such as Oil platforms in the oceans. At current the main fasteners I am using are high tensile steel such as 12.9 grade. The pump is then painted with maritime paint usually to customer specifications. The problem is that the environment is getting through the paint and attacking the bolts and I fear is weakening these bolts. Can anybody recommend to me any grade of material for the bolts which give me better resistance to the environment but at the same maintain the tensile strength? I have thought of materials such as Inconel 718 but this is very expensive and I was hoping for some other suggestions?
Kind regards
Anthony





RE: High Pressure Corrosion resistant studs needed
Alloy like K-500 Monel are traditional, alloys such as 625, 255 and 2507 have also been used successfully. There are also some high strength Cu/Ni alloys that have been used.
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Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
RE: High Pressure Corrosion resistant studs needed
Stainless steels, even some of the highly alloyed ones, may need cathodic protection, which is why Ni and Ti alloys are used in spite of the higher material costs.
By the way, painted 12.9 is likely a disaster waiting to happen.
Regards,
Cory
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: High Pressure Corrosion resistant studs needed
RE: High Pressure Corrosion resistant studs needed
The duplex grades (2507 and 255) will reach higher strengths than the 6%Mo alloys.
= = = = = = = = = = = = = = = = = = = =
Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
RE: High Pressure Corrosion resistant studs needed
RE: High Pressure Corrosion resistant studs needed
= = = = = = = = = = = = = = = = = = = =
Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
RE: High Pressure Corrosion resistant studs needed
RE: High Pressure Corrosion resistant studs needed
DACROMET is a zinc flake coating, when applied, thickness is about 10 (ten) microns.
For more details, see:
http://www.dacral.com
RE: High Pressure Corrosion resistant studs needed
Regards,
Cory
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.