PDCL Series positive-displacement liquid flow calibrators

PDCL Series positive-displacement liquid flow calibrators cover flows ranging from 0.01 gal/min (0.04 L/min) to 400 gal/min (1,514 L/min) with an uncertainty of ±0.05% and a repeatability of 0.01% of reading. These volumetric devices displace an exact known volume of fluid, which passes through the flowmeter under test while compensating for fluid viscosity and temperature. They perform NIST-traceable calibrations of common flowmeters, including turbine, differential-pressure orifice plate, rotameter, variable area, coriolis, and any other type with a visual, pulse or analog output. Each PDCL calibrator has a precision-honed and polished cylinder assembly, with a piston mechanically connected by a displacement shaft. Piston travel is measured with a high-resolution linear encoder. One piston side is actuated pneumatically, while the other displaces a controlled amount of fluid through the meter that is being tested. Flow is regulated by three control valves — course, medium and fine — to obtain the required flowrate. The fluid is collected in a reservoir tank and returned to the cylinder, bypassing the tested meter. A temperature control system maintains fluid temperature to create the desired calibration conditions. The calibrator can be fully automated to establish flowrates and collect calibration data. Other automated features include automatic fluid air bleed; a servo-driven, telescoping flowmeter section; and a flowmeter-clamping fixture.