English to Russian Tech/Engineering Petroleum Eng/Sci

Blowing and Inspection
Blowing starts with slowly pressurizing a medium inside a reservoir (not more than the maximum permissible rated pressure).
Starting with a lower pressure and further increasing as the process is repeated is required as too high pressures are a safety issue.
After reaching the desired pressure of 5 barg, the medium is blown through the system with velocities greater than the process design speed.
Normally the blowing velocity should be over 50 m/s.
Following picture shall serve as guideline regarding the hose arrangement required to achieve necessary velocities at 5 barg independent from the buffer volume:
2 hoses 1”
2 hoses 2”
1 hoses 4”
Referred Range
2 hoses 4”
1 hoses 6”
2 hoses 6”
3 hoses 6”
4 hoses 6”
3 hoses 8”
Pipe diameter [inch]
Maximum initial flow velocity [m/s]
Blowing is reached through quickly opening a manual ball valve for kinetic blowing or monitoring the pressure to a point at which the installed rupture disc burst.
In general, one way shall be blown at a time to make sure the highest air flow possible is utilized.
In case the desired blowing duration cannot be achieved using the available buffer volume, then the vessels, drums or columns in the system can be filled initially and used as air buffers during blowing activity.
Pressurize these pieces of equipment up to about 2-5 bar (not more than the maximum permissible rated pressure).
The connected lines then can be blown.
Only in case piping is proven to be secured sufficiently blowing pressure can be done with pressures higher than 5 barg.
Following picture shall give an indication about the expected duration of each blowing step for a line to be cleaned of 16".
The hose size assumed for the estimation is 6".
1 hoses 4 bar-g
Buffer Volume [m3]
1 hoses 7 bar-g
1 hoses 10 bar-g
3 hoses 4 bar-g
3 hoses 7 bar-g
3 hoses 10 bar-g
Blowing time
The process has to be carried out as marked up in P&ID and repeated until the required cleanliness class is fulfilled.
It must be checked visually whether noticeable particles leave the blow out point.

If cleanliness has to be checked especially carefully, use impact bleeds and count number of impacts.