MUELLER
®
Shur Stop
TM
Unit 68 PE Line Stopping System
Operating Instructions
11
47. Make the repairs.
48. Before decompressing the
the sealing ring, it is necessary to
equalize the pressure upstream and
downstream of the same stopper.
When only gas comes out of the
vent No. 2, close the respective
gate valve letting the gas equalize
pressure. It is now possible to test
the new connections (
r.
).
49. Decompress the sealing ring of
the stopper by operating counter-
clockwise on the ratchet handle
until a hard stop and retract the
stopper inside the stopping machine.
50. Repeat the same operations on
the second stopping machine (
s.
).
51. Close the related slide gate
valves (
T.
).
52. Bleed the gas contained in
the by-pass at a suitable distance
from possible sources of ignition
(
U.
)
53. Remove the by-pass and the
stopping machines (
v.
).
U.
Bleed Valve
T.
Vents Closed
No. 1
No. 2
s.
Vent Closed
No. 1
No. 2
v.
No. 1
No. 2
r.
No. 1
No. 2
Hose
Vent open for Purging
