OQ-1651 - Purge Flashcards
(26 cards)
What is purging?
Displacement of air with gas
Displacement of gas with air
Removal of foreign materials, such as water and debris in a safe matter
What are three mediums introduced into the pipeline to replace an existing substance
Air gas, nitrogen
What is a medium?
A medium is a substance in a pipeline to replace an existing substance
What pressure must not exceed during purging?
The maximum test pressure for the pipe for new pipelines
The MOP for existing pipelines
What is the maximum pressure allowed during a purge for an new facility?
1080
What is the maximum pressure allowed during a purge for an existing facility?
45psi
How do you verify you do not exceed the maximum pressure during the purge?
Pressure gauge and that is open to atmosphere
When is the turbulence slug created?
If the air and gas is mixed together
Are you supposed to notify dispatch anytime you purge?
Yes, and we do this so that odor calls can be expected
True or false at least 20 label fire extinguisher must be ready and available in the immediate area
True
What must the purge deck not be directed at?
People
Animals
Doors
Window
Eaves
Equipment
Sources of ignition
Powerlines
Prior to touching any company metallic facility, MSA what should we use to check for the presence of electricity on both sides of the MSA insulator?
Voltage detector
When purging risers are you supposed to have grounds to a ground plate or rod and attach the ground wire to a stop cock valve or still purge stacked to ensure proper grounding?
Yes
True or false all purchase must be verified with a confirmation instrument
True
What must the confirmation instrument readings be when purging
Obtain a minimum of 90% gas readings when purging then immediately close purge point
How much percent of gas should we obtain when purging with air?
Approximately 0%
True or false when purging a purge of multiple risers as a result of an outage risers at the farthest end of the man should be utilized to facilitate the purge
True
When purging sections of pipe located within an excavation that are longer than blank feet a purge stack must be used
5 feet
Purge stack must extend a minimum of blank feet above grade
6feet
When purging Lily installed mains and services over 500 feet in length and 2 inches or larger what is required
A minimum of a 2 inch purchase assembly must be utilized and ensure proper flow for a complete purge
The connection of the purchase assembly should be located directly in line at the end of the main or service
What tool do we use to Hydro test
The dewpoint
What do you use to isolate the active pipeline by using boundary points?
Line stopper cut in cap valve squeeze
The water and/or debris must be removed using one or a combination of the following methods
Purging from one or more boundary points to one or more vent points
Line sweeping the process of pressuring a close line and then releasing the pressure quickly 
