In addition to verifications and calibrations pigsar™ offers further services.
Other pressures and gases
In association with the Federal Institute of Physics and Metrology (PTB), pigsar™ can also issue certificates for other pressures (0.1 to > 10 MPa) and other gases (air, N2, CO2, …), where necessary based on further tests (calibration with air at atmospheric pressure at PTB).
Statistical testing of ultrasonic flowmeters ("dry calibrations")
Ultrasonic meters (USMs) are often used at much higher pressures than the pressures available at the test facility. To minimise the influence of the calibration pressure, pigsar™ offers statistical tests with natural gas (at zero flow). These test have already been performed frequently for pressures of up to 25 MPa.
Calibration (by “derivation”) of other test facilities
pigsar™ provides the calibration bases for the working standards of numerous other test facilities. Derivation methods can vary depending on the uncertainty of measurement required. Many test facilities have their working standards calibrated at the pigsar™ premises. Another option is to use transfer meters (also known as "travelling standards") which are made available by pigsar™.
Special calibrations against the national standard
In collaboration with PTB we also offer direct calibration of customer meters using the national standard. Turbine flowmeters, low-pulsation rotary piston flowmeters and critical nozzles can be calibrated directly against the primary standard – the high-pressure piston prover – in the flow range Qa= 3 to 480 m³/h, and at pressures of p = 0.8 to 5.5 MPa. While these tests require more time and effort than standard tests, they offer the best measurement uncertainty (around U95 % = 0.1 %).
Thorough testing at HDV Lintorf
Customers can also place an order with pigsar™ for tests OGE’s HDV Lintorf test facility under typical operational influences and for approval tests (PTB, MID). All influences that can occur during metering system operation (upstream flow perturbations, flow regulator influence, etc.) are examined in detail for their impact on flow measurement. Lintorf uses natural gas at a pressure of 10 to 40 bar for testing meters with nominal diameters of DN 100 to 300. The flow range is 10,000 to 75,000 m3(n)/h.