7
Kleiss MCS60-38 System Manual v.15 May 2020
|
www.MainlineControlSystems.com
Example II – Stopping Sequence: Stoppers Positioned Away From Work Area
Example II – Stopping Sequence: Stoppers Positioned Away From Work Area
STOPPING TOWER DISTANCES
Nominal Pipe Size
A
(
minimum
)
B
L1 = Steel Welding
L2 = PE, CI, and Mechanical
3”
20”
20”
18”
9” *
4”
22”
22”
24”
12” *
6”
26”
26”
30”
18” *
8”
36”
36”
36”
24” *
A = minimum distance between towers | B = stopper length | L1 = minimum distance from stopper/tower to work area
L2 = distance from stopper/tower to work area (
*
measurement is a guide only, follow manufacturer’s fitting recommendations)
1)
If a by-pass in the work area is being used (through our MCS tool or another), initiate the by-pass flow first.
2) Always insert first inflatable stopper WITH the flow of gas.
3) Always inflate the stopper as quickly as practical.
4) Suggested stopper setting sequence is tower #3, #4, #2, #1. Set all 4 stoppers.
5) First inflated stopper is now in a no flow condition. Reset stopper for best possible seal
(deflate, reposition stopper rod, inflate).
6) Always allow stoppers to settle for 10 minutes prior to beginning pipeline work. This allows the stopper to
acclimate to internal pipe conditions. Verify system pressures, inflation pressures, and any bleed-by before
starting pipeline work. Adjust as necessary.
7)
Use the by-pass / vent port on tower #2 or #3 to purge the work area. Utilize the MCS vent stack to assist in
evacuating the work area. These connections can also be used to inject nitrogen into the work zone.
8) Keep all by-pass / vent ports on towers open to atmosphere during work to keep gas away from the work area.
Follow company procedures for venting and purging gas.
