1- weld
18" Flange to manway lid |
Hot tapping is defined as using an under pressure
drilling machine to cut a hole in an operating oil storage tank
allowing a flange to be fitted through which an NESL nozzle may be
inserted. This process is done without any product leakage or loss.
This operation is safe provided the liquid level in the tank is above
the level of hot tapping. |
2- Bolt
18" valve to flange |
The components for a typical hot/wet tap application
include a 18" flange, a 18" valve used to control the new
connection, and a drilling machine used to make the hot tap.
The following is the basic procedure used to perform
a hot/wet tap.
|
3- fit
drilling machine |
 | Welding of an 18" flange to a tank manway and fitting of an
18" gate valve onto the flange |
 | Install hot tap machine |
 | Perform hot tap through the open valve. A special device retains
the "coupon" removed during the hot tap operation. |
 | Retract cutter assembly. |
 | Close hot tapping valve. |
 | Remove hot tap machine to allow for inserting of the NESL
TanksweepTanksweep" nozzle |
|
4 -
drill through manway lid |
|
5 -
withdraw drill |
|
6 -
close valve |
|
7 -
remove drill |
|
8 -fit |
|
9 -
open valve and insert NES Tanksweep into the tank |
|