Isolation for Maintenance and Repair 1

[shvet]

Good day, forum

I have a question concerning safety precautions for process system (equipment and/or piping) isolation for maintenance or repair. When and why block valve(s), check valve, bleed valve, split plate (blind), spectable plate (blind), blank flanges are to be used and its combinations? When and why physical disconnection, squeeze off, foam bagging, pipe plug, freezing are to be used?

I know that ask much but I need documents - engineering practices and standards. The only suitable document I have found is HSG253. Can one provide with links to worth documents concerned?

Links to incidents and accidents statistics are welcomed.

 

[DGrayPPD]

Process Industry Practices (PIP) has many different standards and practices that you can reference. See the link below.

https://pip.org/practices

"Thinking is the hardest work there is, which is probably the reason why so few engage in it."

-Henry Ford

 

[EmmanuelTop]

Google "process equipment isolation standard". You'll get access to PDO and BP standard procedures.

https://www.bp.com/content/dam/bp-c...l-work/PRO_4_5_0001_1_02-energy-isolation.pdf

Dejan IVANOVIC
Process Engineer, MSChE

 

[LittleInch]

hsg 253 is pretty good as a guideline.

Most operators then develop and maintain an isolation philosophy relevant to their locations, fluids and perceived risks.

As these vary widely, then so do the agreed means of isolation.

Determination of where the specific items are applied is by the design engineers, typically the process engineers, using the philosophy which is then picked over by other disciplines including technical safety and then discussed in the HAZOP.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[chicopee]

Isolation is one aspect. The second aspect is to trigger the equipment connected to the piping to ensure that there is no rediduals left in the equipment and piping.

 

[geesamand]

I know you're looking for documents, but cost and speed of repair is of immense importance.

So for example, the cost to pump down a tank, clear the headspace of toxicity, confined space entries, and additional lost time could be easily estimated to justify shutoff/block off features in the wearing equipment. Keeping workers separated from hazardous areas too. That's pretty hard justification.