2 replies to this topic

[omr022]

Hi to every one,
I am operations engineer (Chemical Engineer) in Hydrocatalytic Cracking Unit (Vac Residue). My team leader ask me to prepare a book has the procedure of isolating equipment like heat exchanger, vessel, reactor, distillation column...etc then to handover to maintenance.

As you know that every one has his own procedure for isolating process. I want your help to find the correct procedure for the isollating procedure.

Your help is highly appreciated.

Regards

[djack77494]

Achieve mechanical and electrical isolation that is appropriate for the equipment access that is needed. Your query is extremely general, so only a very general response is possible. If you'd like more, be specific. For example, "I'd like to isolate a centrifugal pump for replacement of the impeller. Suction pressure is near atmospheric and discharge is 6 barg or 90 psig. Pumped material is a heavy hydrocarbon at 100C or 200F. Other parallel pumps will remain in operation."

Edited by djack77494, 22 October 2009 - 05:48 PM.

[Rush]

Hi to every one,
I am operations engineer (Chemical Engineer) in Hydrocatalytic Cracking Unit (Vac Residue). My team leader ask me to prepare a book has the procedure of isolating equipment like heat exchanger, vessel, reactor, distillation column...etc then to handover to maintenance.

As you know that every one has his own procedure for isolating process. I want your help to find the correct procedure for the isollating procedure.

Your help is highly appreciated.

Regards

Generally, for heat exchangers, vessels, and columns, positive isolation is required For either man-entry, or for general maintenance. Positive isolation can be in the form of a removable spool piece or spectacle blinds. These must be provided on all entry/exit points to the vessel.
For instrumentation, depending on the type of instrumentation, a single block or double block valve(s) may be needed, upstream the instrument, along with a bleed. this would probably be dependent on the type of instrument, (safety / control) and if it is a level/pressure/flow instrument.

safety instruments need locked open valves upstream the valve, and in the cae of multiple/spare relief valves interlocked valves.

The list goes on...utilities, drain connections, tanks, compressors, pumps etc
also the type of isolation needed will differ from vessel to vessel, depending on the pressure rating, and the hazard/danger that may be posed.

I suggest, finding an isolation guide, from one of the more reputable companys, and read through it, and then go through the P&IDs with a fine tooth comb, tackli9ng each category at a time

maybe if u like,
upload one of the P&IDs so someone here can show/explain the concepts on it and then use that as an example.

Just my 2 cents.