The equipment requiring sealing are defined in this Procedure.
SEALING REQUIREMENTS | PROCESS & CONTROL SYSTEM
Frequency: As listed
Procedure The following items shall be sealed after each calibration:
Meters:
Calibration or gear adjuster, temperature compensation, totalizer/printer head, head counter.
Common seal points for displacement meter installations are meter cover and accessory stack flange bolts, meter counter mounting bolts, calibrator and compensator adjustment, right angle drive covers and covers for electrical conduits and control boxes.
Common seal points for turbine meter installations are the mechanical counter enclosures pick up mounting fittings, preamplifier housings, electrical conduit covers and control box covers.
Common seal points for coriolis meter installations are the electrical conduit covers and transmitter housing.
Instruments:
Local or remote totalizer, electronic Preset/meter K factor knob if applicable.
Valves:
Valves on lines that bypass a meter shall be sealed closed. Valves on lines that are not in normal use shall be blinded or sealed closed. Seals on connection valves between the metering system and custody transfer point shall be installed and inspected.
Prover:
Seals are installed with unique identifiers on critical prover components (e.g., prover switches, tank prover neck scales, etc.) and to record the seal identification numbers on the prover calibration certificate.
Other measurement devices:
Such as the preset control and flow computers shall be sealed and/or password protected to prevent unauthorized tampering and to protect integrity of data. Access to the transmitter software program is often protected by password security.
Sealing electrically operated systems that have many accessories, power supplies and readouts become burdensome.
In these cases it is acceptable to have equipment locked in a building or behind a secured gate.
FLOW RATE CALCULATION AND COMPUTATION CHECK PROCEDURE
Field Instrumentation Design Criteria
PIPE PROVER CALIBRATION BY MASTER METER