2350 Industrial Road, Sapulpa, OK 74066 • Main: 918-445-1141 • sales@weamco.com Bulletin MPD-112 Toll Free: 800-331-3790 • Fax: 918-445-4617 • www.weamco.com 5-19 Page 6 of 8 Conventional Liquid Meter Provers Design and Construction VI. Prover Accessories and Trim: 1.  External paint, heat trace and Insulation 2.  Drain valves, block & bleed type or Arrangement 3. Vent valves 4. Pressure gauges 5. Thermometers 6. Pressure relief valves 7.  Pressure and temperature transmitters 8. Field calibration connections 9.  Sphere by-pass for vertical or Inclined launch chambers 10. Skid mounted  Weamco always specifies and uses high quality accessories and trim equipment. VII. Calibration  Prior to placing a prover into service, a base prover volume must be determined. This is done by a water-draw calibration as outlined in API Chapter 4, Section 9, as previously mentioned, and calculations per API Chapter 12, Section 2 Part 4. The calibration also verifies that all components are sealing properly and are in working condition. In particular the 4-way diverter valve. The calibration is completed using field measures, thermometers, and gauges that are traceable to NIST, per API Chapter 4.7.