FIXED-ORIFICE
FLOW INSTRUMENTS

Fixed-Orifice Flowmeters

Our flowmeters are designed for those applications where a rotameter is not appropriate. Consider the inherent problems of rotameters--they are difficult to read, especially with dirty or opaque fluids, have low pressure ratings and allow vertical orientation only. Now consider that our models have large dials with bold markings and characters that are easy to read from a distance, handle high line pressures and can be mounted in any orientation.

Like rotameters, they are mounted directly in the flow stream, but with bodies machined from solid blocks of metal, they handle high-pressure applications of up to 3000 psi (vs 150 psi for rotameters). This makes them a natural for hydraulic and pneumatic systems.

These fixed-orifice models are designed for low flow applications. We use a fixed Delrin orifice centered on a Buna-N diaphragm (Viton is optional), which provides sensitive responses to changes in flow. The rate is displayed on an easy-to-read, square-root-calibrated dial face.

We offer them with bodies (and wetted parts) of aluminum, stainless steel or brass. A variety of dial sizes are also available, from 2.5 inch to 4.5 inch. Choose from a wide selection of standard options; enough to satisfy any requirement.

Switches, Relays, Transmitters

A variety of reed switches, relays and transmitters can accompany the meters or be supplied on their own, without a dial. SPST switches are offered normally open (N.O.) or normally closed (N.C.). SPDT reed switches are also available. DPDT relays are offered for high inductance applications, such as those incorporating motors or solenoids. Transmitters offer a wide variety of outputs, such as voltage, current, frequency or RS 232.

Calibration

Liquids

For liquids our meters are calibrated to customer specified specific gravity and viscosity of the fluid to be measured (up to 150 CS). Otherwise, standard calibration is on water at 70 F. For oil service, meters are calibrated using oil (specific gravity 0.86 CS at 74 F). Special calibration is available to meet customers' specific gravity and viscosity requirements using selected fluids and a conversion procedure. Standard calibration is for horizontal mounting; vertical is offered at no charge.

Air and Gas

For air and gas applications, our meters are calibrated on air at 100 psig at 70 F. For non-standard fluids or conditions, a conversion procedure is required. Because gas is compressible, please supply pressure and temperature conditions and type of gas when the order is placed so that the density of the gas can be taken into account and noted on the dial face.