Unitary electromagnetic flowmeter

Abstract

A highly compact electromagnetic flowmeter unit interposable between the flanged ends of upstream and downstream line pipes for metering fluid passing through the line, the unit being subject to compression by these flanged ends to effect a fluid seal. The flowmeter is constituted by a non-magnetic metal spool of high strength whose inner surface is lined with insulating material to provide a flow conduit for the fluid to be metered, the spool also serving to withstand the compressive forces to which the unit is subjected as well as the fluid pressure. Surrounding the spool and concentric therewith is a cylindrical housing fabricated of ferromagnetic material, the housing being preferably formed by complementary half-pieces which are interconnected and include end plates which join the corresponding ends of the spool to define an inner chamber. Integral with the half-pieces are two magnet cores which extend at diametrically opposed positions along an axis normal to the longitudinal axis of the cylindrical housing, the cores being surrounded by coils to define electromagnets. Mounted on the spool at diametrically-opposed positions along a transverse axis at right angles to the core axis are two electrodes. The inner chamber is filled with a potting compound to encapsulate the electromagnets and the electrodes, the housing serving as a mold for this purpose.