We used many hastelloy C276 gasketting plate exchangers in other service (H2SO4/sea water). We had many problems for crevice.
Now we are evaluating the propose to use a new titanium welded plate exchanger (compabloc) in FCCU Head main column service.
I haven't any experiences about this new...
The corrosion under gasket is a typical corrosion form named Crevice. It's the main problem for this type of austenitic or duplex steel in sea water enviroment (Cl- presence) with high operative temperature (>70°C reached in this case limited no-flow zone of floating camera under gasket). The...
These exchangers cool the main column head gas by water sea
Alfa Laval proposed 3 Titanium welded plate exchangers for this service (Compablock Titanium grade 1 plates , T=80-100 °C, 3000 ppm h2s, 1500 ppm Nh3, <10 ppm CN, 0 ppm Cl).
API 571 par 5.1.3.2 advise for hydriding risk (NACE MR175 par...
You understood exactly the problem.
I recived from Klinger the firesafe certification relative to their Topchem 2000 gasket type.
The certification recived is about a test DN50 PN40 30 bar TOPCHEM 2000 GASKET (107x60x1,5mm) based on the "specification for fire test for Valves" according to API...
In regenerating H2SO4 plants it's often necessary to weld some patchs on pipe or equipment (carbon steel type) with liquid acid inside to eliminate leakages or add corrosed thickness.
Often it's very difficult to clean very well the metal surface before welding.
This is a very dangerous practice...
Sorry Mr Lamberson
I found the italian Exxon hot tape procedure.
It has a different approach to the problem considering the temperature during the welding operation
It permit hot tape with 5 mm minimum tickness
It give at first the welding penetration percent expected (%p) based on the...
The problem is relative to pipeway where many hydrocarbons pipeline run near the acid pipe. In the last year we had a very big fire that destroyed all pipeline. But the problem is inside the alkilation plant too where there are many light hydrocarbons products
We have one H2SO4 regeneration...
Does someone know a commercial type of fire-protection split bolted shell to protect some ptfe internal lined metallic bellows or ptfe fully lined metallic ball valves?
Dn100 and DN200
Thanks
Aldo Cigna
I've found in the Klinger internet web site the PTFE gasket type Top-chem-2000. It's an API6FA firesafe certified gasket. Perhaps it is a possible solution.
I've found in the EngineeringValves internet web site some firesafe certified metallic ball valves with a PTFE metal renforced seat...
I've found in Klinger internet web site the PTFE gasket type Top-chem-2000. It's a API6FA firesafe certified gasket. Perhaps it is a possible solution. Do you know something about it?
Thanks very much
Tx Mr Lamberson
Your answer is very usefull for me.
If possible, I would know if your answer is a your personal opinion or is an official interpretation by API organizzation
Thanks again
What type of firesafe certified gaskets is possible to use in H2SO4 92-98% service (max 100°C)? I asked about Grafoil gasket but the chemical compatibility table of this material show it like non recommended in H2SO4 service over 95%
Could you help me?
Thanks
Aldo Cigna
In my refinery many PTFE modified gaskets (Garlock Red Gylon type) are used in H2SO4 piping. Recentely many PTFE lined ball valves are used too.
I want know your opinion and your experiences about the firesafe property of this material inside the Alkilation plant and inside the pipeway outside...
The API RP2201 reccomended a minimum metal thickness like a function of the thickness required for strenght plus a safety factor (usually 2.4 mm) to prevente burn through.
I don't understand very well what temperature i've to use to calculate the thickness for strenght. If this temperature is...
I've used API579 (fitness for service)appendix F table F2 to recalculate yield stress and ultimate tensile stress for S275JR steel at 90°C.
The original values 275/430 Mpa became 252/414 Mpa
I hope this right
I've used API579 (fitness for service)appendix F table F2 to recalculate yield stress and ultimate tensile stress for S275JR steel at 90°C.
The original values 275/430 Mpa became 252/414 Mpa
I hope this right
Two storage tanks worked at 50°C. The shell plates material was FE430B (equivalent S275JR)
Now the storage tanks have to work at 90°C and we changed the shell plates using the same material (S275JR)
Is it correct? is this material a correct material at 90°C design temperature for API650 or...