FlowTrac II is an intelligent, versatile pressure and volume control flow pump with all necessary components and sensors self-contained. The flow pump, which regulates pressure and volume in a test cell, houses a high speed, precision micro stepper motor that moves a piston in a water-filled cylinder. An embedded control board with a dedicated CPU uses readings from the internal pressure transducer to determine response of the stepper motor. The number of motor steps is used to compute volume change. Two-way solenoid valves are used to control the direction of flow to the cell or sample (output valve) and fill/drain operations (supply valve). FlowTrac II can maintain a desired pressure within 0.35 kPa (0.05 psi) while monitoring volume changes within 0.001 cc. Pressure increments may increase and decrease in any pattern by any amount (without exceeding the system’s limits) as specified by the user, even while a test is in progress.
The FlowTrac II system requires no special skills to operate, other than those used in conventional testing. A person familiar with soil testing can learn to use the system confidently within a few days.
FlowTrac units are used to provide cell pressure and back pressure in triaxial testing, back pressure for constant rate of strain consolidation testing, back pressure and consolidation for hydraulic consolidation (Rowe Cell), and cell pressure, inflow pressure, and outflow pressure for permeability testing.