Manholes of a vessel

[HOUARI YAHIAOUI]

Hello Experts;
The question : is there a limitation of manway/manhole size related to the inner diameter of the vessel? I mean is there o formula or standard/norms that give a relation between the size of the vessel and the size of manholes?
Thank You

 

[LittleInch]

24" is the smallest possible to get into and even that's a squeeze sometimes if the vessel is small.

Then it depends on what things you want to take in and out, but a 30" manhole makes it a lot easier.

But no formula I am aware of - it's a practical access issue for repairs, maintence and initial installation of internal components


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

 

[david339933]

Yes....see UG-46.

 

[MJCronin]

https://www.eng-tips.com/viewthread.cfm?qid=160574

Also see EN 13445 ....

LittleInch: 24" manways are nice and comfortable.... but there are many 18" round and oval manways out there.

There is a reason why companies hire little skinny guys to work inside boiler drums ...

MJCronin
Sr. Process Engineer

 

[r6155]

All pressure parts require access to all inside surface of the shell wall for in-service inspection, therefore some pressure vessels need more than one manhole.

Regards

 

[Dhurjati Sen]

Well said @ MJCronin

DHURJATI SEN

https://www.nace.org/people/dhurjatisen

 

[mk3223]

IMO, although the Codes may specify the required minimum size of the handhold/manhole for the vessel, the Client Engineering/Maintenance guidelines of the required size may be followed for designing as suitable for the diameter of the vessel.