2020 Tech Report Jan-Feb

Task # 2.b.: Cleaning a Strainer in a Configuration “B” Control Group: Gauge Valves

ACTION

COMMENT

NOTE: Refrigeration Operators / Technicians must follow the facility’s Lockout / Tagout Pro- gram. If you have any questions while perform- ing this procedure, refer to the equipment’s corresponding SOP, consult your supervisor or the facility contact, or review the facility’s Ammonia Refrigeration Compliance Program.

2.

Verify the isolation of other forms of en- ergy to the valves being worked on.

3.

Slowly close Valve “A.” Apply lock and tag per the facility’s Lockout / Tagout Pro- gram. Change the automatic valve’s manual operating stem to the “MANUAL OPEN” operating position. Valve “B” Regulator Allow the section of piping with the control valve to pump down before continuing. Lower the pressure in the isolated sec- tion of the piping to the lowest pressure available.

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6.

A lower pressure portion of the system may involve manipulation of compressor set points or utilizing hoses to other portions of the sys- tem. NOTE: Any frost on exposed portions of the pipe or valves should disappear with the liquid ammonia in the system. NOTE: If the isolated piping is in a vacuum, take precautions to prevent water being drawn in when purging the piping.

7.

Slowly close Valve “D.” Apply lock and tag per the facility’s Lockout / Tagout Pro- gram. Slowly close Valve “C” or verify that it is already closed. Carefully remove the gauge or plug from Valve “C.”

8.

If the configuration is per Figure #2, Valve “C” does not have a gauge and should be closed and plugged.

9.

RETA TECHNICAL REPORT PAGE 11