Paddlewheel Flow Meter with Improved Servicability and Improved Reliability Under Harsh Operating Conditions

摘要

In a flow meter, a rotor support body carries a paddlewheel rotor in an operational position exposed to a through-flow bore of a flow meter housing. A sensor unit is operable to detect rotation of the rotor and provide output responsive to same for use by a monitoring system in determining a flow rate of fluid passing through the housing. The support body and the sensor unit are removable from the housing, for inspection, service, repair or replacement independently of the housing, with the sensor unit being removable independently of the support body for improved serviceability. The rotor is carried on a support shaft with a reduced diameter portion for contact-free rotation of the rotor around this reduced diameter portion, reducing an area of the shaft over which tight machining tolerances are required to prevent ingress of particulate matter that can lead to inaccurate flow measurements and increased wear rates.

主权项

1. A paddlewheel flow meter comprising:
a housing having an internal through-flow bore passing therethrough on a flow direction axis, and an internal mounting bore extending into the housing on a mounting bore axis transverse to through-flow bore and opening into the through-flow bore; a rotor support body having inner and outer ends spaced apart along a longitudinal axis and a paddlewheel rotor rotatably supported for rotation about a rotational axis lying transverse to the longitudinal axis in a hollow rotor cavity of the rotor support body adjacent the inner end thereof, the rotor support body being arranged for removable receipt thereof in the mounting bore at an operational position in which the paddlewheel rotor reaches into the through-flow bore for driven rotation of the paddlewheel rotor by movement of flowable material through the through-flow bore; and a sensor unit arranged for removable receipt in the mounting bore at an installed position placing a rotational sensor of the sensor unit at a useful position operable to detect rotational motion of the paddlewheel rotor about the rotational axis; wherein the sensor unit and rotor support body are distinct units that are replaceable separately of one another, thereby enabling replacement of the sensor independently of the rotor, or vice versa, by replacement of only one of the sensor unit and the rotor support body.