Abstract: A signal processing system that directly determines the phase difference existing between two periodic electrical signals and a mass flow meter employing the system are provided. The system shifts together two comparison signals corresponding to the periodic electrical signals and accumulates the shift that is necessary to force the phase angles of the comparison signals to be equal. The mass flow meter employs a moving conduit through which the fluid whose mass flow rate is to be measured flows and which generates Coriolis forces. The Coriolis forces affect the motion of the moving conduit and motion sensors provide periodic signals corresponding to the motion of the conduit. Under flow conditions, the Coriolis forces cause the electrical signals produced by the sensors to be out of phase with each other to an extent that depends on the magnitude of the mass flow rate.

Abstract: A flow prover with seal monitor includes a housing with a cylinder and a piston-like displacer sealingly conveyed along the cylinder by the fluid flow to be measured. The displacer includes at least one rod that extends telescopically through the housing. A pair of conduits may be arranged concentrically within the rod, one in communication with a volume between a pair of seals whose integrity is to be monitored and the other in communication with the fluid in the housing. The conduits each communicate as well with a pressure sensor located outside of the housing. The sensor may be mounted on the rod to sense the absence of a pressure differential between the conduits, which indicates a seal failure. The sensor may provide an indication, which may be detected at the end of a proving cycle, that the seal integrity was maintained throughout the proving cycle.

Abstract: A dynamic type of mass flowmeter is disclosed in which an S-shaped conduit with supported ends is vibrated in a direction transverse to the plane of the conduit, and the force couple about an axis orthogonal to the longitudinal axis of the S-shaped conduit and also to the direction of vibration is sensed as a measure of the mass flow rate through the conduit.

Abstract: A compact flow prover for calibrating continuous flowmeters includes a measuring housing comprising a main cylinder having a substantially uniform inside diameter and inlet and downstream sections having inside diameters greater than the main cylinder. The compact flow prover is provided with a displacer movably disposed within the housing having seals which form a fluid barrier while the displacer is disposed within the main cylinder. Inlet and downstream section guide means are provided to maintain the displacer in axial alignment with the main cylinder while the displacer is disposed within either of these sections, assuring smooth exit and entry. The displacer is provided with seals which are circumferentially compressed when the displacer enters the main cylinder and may be statically or dynamically monitored for integrity without an external pressure source.