Multi-range vortex-type flowmeter

In combination with a flowmeter of the vortex type in which an obstacle mounted in a flow tube includes a block fixedly mounted across the tube at right angles to the direction of fluid flow, the front face of the block being presented to the incoming fluid, said block having a predetermined geometric configuration whose cross-sectional area is uniform through its longitudinal axis, a replaceable adapter cap fitting over the front face of the block, said cap having a longitudinal channel therein which conforms to the profile of the block and acts as a socket therefor, said cap having a formation effectively expanding the cross-sectional area of the block without altering its geometric configuration whereby the resultant expanded block restricts the effective area in the flow tube of the fluid passing by the block, thereby making it possible to measure flow rates below the normal operating range of the meter in the absence of the cap.