VENTURI FLOWMETERS. Your First Choice in Intelligent Flow Management...

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1 VENTURI FLOWMETERS Your First Choice in Intelligent Flow Management...

2 VENTURI FLOWMETERS Preso s complete line of Venturis offer reduced operating costs, proven accuracy, and great rangeability. Low permanent pressure loss characteristics, due to the Venturi s unique Low-Loss design, reduce energy costs and result in the lowest operating cost of any such device on the market. Available in a variety of materials and configurations, the Venturi is suitable for a wide range of conditions in Water/Wastewater, Industrial, Institutional and HVAC applications. The Preso Venturi has been tested and proven in the field by recognized flow laboratories and insurance underwriter agencies.

Characteristics Accuracy: + 1% of readings uncalibrated, +

DP Reduced Pumping Costs Resists wear, maintenance free (no

Venturi design Easily installed in any position with minimal

diameters downstream) Sizes 1/ to 48 and larger upon request

3 Characteristics Accuracy: + 1% of readings uncalibrated, + 1/4% calibrated (tested at CEESI, Alden, NRCC, NBS traceable) Repeatability: + 0.1% of readings Turndown Ratio: 10/1 Max Pressure Loss: 6% of DP Reduced Pumping Costs Resists wear, maintenance free (no moving parts) Short form, lighter weight than any other Venturi design Easily installed in any position with minimal straight pipe requirements (5 pipe diameters upstream and pipe diameters downstream) Sizes 1/ to 48 and larger upon request Manufactured to standards such as: ASME, ANSI B31.1 and CSAZ99.3 or equivalent ISO-9001 certified design and fabrication

4 Preso Designs the VENTURI Tube to Meet Every Individual Customer s Requirements Classical Design (Hershel Type SSL) The Classical Style Venturi Tube is designed in accordance to ASME and/or ISO standards and will offer excellent accuracy and high repeatability. Hydraulic Shape Design (Venturi-Nozzle Type SSM) The Preso Hydraulic pure static design utilizes the proven classical ASME and ISO standards for highest accuracy, predictability and repeatability. The flow conditioning generated by the unique hydraulic shape will provide an extremely stable signal in a wide range of flows. Low-Loss Design (Short Form Type LPL) Preso can relate to the success of the Low-Loss design which amounts to over 35 years of proven field performance in a wide variety of applications. The reduced costs of operating inherent with the design, will pay for itself in the shortest of time. Low installation costs due to short laying length and the wide range of sizes and materials of construction, make the LPL the right choice for many flow applications.

5 Cast Iron This series is made according to specifications required with the finest quality ductile or cast iron to ATSM standards. The Venturis are machined to the closest tolerance with optional bronze or stainless steel throat sections. Sizes Available: -1/ to 60 End Connections: Flanged or wafer. Temperature and pressure ratings according to materials used. Can be supplied with or without piezometric rings. Fabricated Steel This series is available in various materials to be specified. Standard executions include one-piece type, manufactured from barstock, forgings, welding sheet or combinations. Machining to the closest tolerance and options of coatings and various finishes are available. Sizes Available: 1/ to 60 and larger. End Connections: Threaded, sweat, weld ends, grooved, flanged. Temperature and pressure ratings according to materials used. Can be supplied with or without piezometric rings. Fabricated Shell This series is available in various materials to be specified. Standard executions include welding sheet, pipe shell and combinations. This series is available with formed or machined flow conditioning inlet. Various coatings and finishes are available. Sizes Available: 1/ to 60 and larger. End Connections: Threaded, sweat, weld ends, grooved, flanged. Temperature and pressure ratings according to materials used. Can be supplied with or without piezometric rings. Insert Type This series is available in various materials to be specified. Standard executions include one-piece type, manufactured from barstock, forgings, welding sheet or combinations. Machining or forming to the closest tolerance for the flow conditioning inlet is also available. Can be supplied with or without flowsection, meter run. Sizes Available: 3 to 36. Connections: Insert type to fit between a pair of flanges. Temperature and pressure ratings according to materials used. Can be supplied with or without piezometric rings.

Low-Loss VENTURI Stainless Steel Insert Model VI Our VI product line is available with SSL (Classical) and SSM throat styles as well as our standard LPL design.

Construction & Specifications: Material: Stainless Steel 304 Pressure Connections: 1/4 NPT Standard Optional Pressure Connections: 1/ NPT, 3/4 NPT Optional Instrument Needle Valves: Brass, Carbon

6 Low-Loss VENTURI Stainless Steel Insert Model VI Our VI product line is available with SSL (Classical) and SSM throat styles as well as our standard LPL design. This allows the user to take advantage of the high accuracy of the Classical and SSM designs while maintaining the benefits of the Insert Style Venturi. Construction & Specifications: Material: Stainless Steel 304 Pressure Connections: 1/4 NPT Standard Optional Pressure Connections: 1/ NPT, 3/4 NPT Optional Instrument Needle Valves: Brass, Carbon Steel, Stainless Steel. Flange Installation: ANSI B16.1 Class 15, 50 ANSI B16.5 Class 150, 300 Benefits of the VI include: All Stainless Steel 304 Construction. Low Installation and Operation Costs. Excellent Corrosion and Temperature Resistance. Low Permanent Pressure Loss with the Low-Loss Venturi Insert (typically 3.5% with a beta Ratio of 0.6) provides additional Plant design flexibility. Accuracy + 1% of actual (uncalibrated) and 0.5% of actual (calibrated).

7 Engineering Data Differential Pressure Calculation The basic flow equations for the PRESO Venturi are derived from the Bernoulli s Theorem (Energy Balance), and the Continuity Equation. The most common equations used by the industry, where different units are employed according to the flowing conditions of each type of fluid as follows: (i) (ii) (iii) Liquid ΔP = Gas / Air ΔP = Steam Where GPM C 1 SCFM * SG s ( T f ) ; C 1 = 18.8 * K * D i * C 1 P f F * SG f ; C 1 = * K * D i * Note: SCFM = ACFM * * Lbs/Hr ΔP = ; SG * S (T f C * * * * * SG 1 f F P f 50 T f C 1 = 359 K D i F a ρ f ΔP - Differential Pressure; Inches of Water Column at 68 F GPM - US Gallons per Minute SCFM - Standard Cubic Feet per Minute at 60 F and psia ACFM - Actual Cubic Feet per Minute Lbs/Hr - Pounds Mass per Hour C 1 - Flow Constant K - Flow Coefficient C * D ß / 1 - B 4 C D - Discharge Coefficient ß - (Beta Ratio) d/d i d - Throat Diameter, Inches D i - Inside Pipe Diameter, Inches F a - Thermal Expansion of the Pipe: 1 up to 100 F/ ( F) T f - Flowing Temperature, F P f - Flowing Pressure, psia SG f - Specific Gravity at Flowing Conditions SG s - Specific Gravity at Standard Conditions (60 F, psia) ρ f - Flowing Density, lbs/ft 3 F a F a Water Test Calibration of a 30 Venturi Meter Model: CV , 30 sch. std. D i : 9.50 and V , 6 sch. 40 D i : Alden Research Laboratory Inc., June 1986, P.O C D Reynolds Number (based on pipe diameter) 100,000 *Discharge Coefficient (C D ) + ¼ % Air Test Calibration of a 1½ and 3 Venturi Flow Meters 3 sch. 40, D i : 3.068, 1½ sch. 40, D i : Colorado Experiment Engineering Station Inc. S/N: S/O 8655, P.O. 435, May 1988 C D Reynolds Number (based on pipe diameter) 100,000 *Discharge Coefficient (C D ) + ¼ % ΔP Calculation Examples: 1) 8 sch. 40 pipe, water flow, 500 gpm base conditions, using Model - 38: 500 ΔP = ; C 1 ΔP = H O * 30 Beta.6017 * 6 Beta * 3 Beta:.60 * 1½ Beta:.81 C 1 = * * (7.981) ) 1 sch. 40 pipe, air flow, standard conditions (60 F and psi) 5 SCFM, using Model -10: ΔP = 5 ( ) * ; * CS F C 1 = 18.8 * * (1.049) ΔP = H O

Pressure Loss With the Low-Loss Venturi PRESO offers the lowest pressure loss of any differential pressure producer of its kind.

80 70 60 50 40 30 0 10 0 Hershel Venturi Flow Nozzle Orifice Flange Taps Hammel, Dahl, Foster - Gentile Tube Dall Tube PRESO Low Loss Tube 0.3 0.4 0.5 0.6 0.

A low-loss tube frequently pays for itself in 6-8 months of continuous use. Installation 1. The primary station can be installed in any position on vertical or horizontal lines.

For horizontal air or gas lines, install the element with the connections on or near the side above the horizontal centerline.

8 Pressure Loss With the Low-Loss Venturi PRESO offers the lowest pressure loss of any differential pressure producer of its kind. Low Permanent Pressure Loss Low-Loss tube (typically 3% with a beta ratio of 0.75) provides additional plant design flexibility Hershel Venturi Flow Nozzle Orifice Flange Taps Hammel, Dahl, Foster - Gentile Tube Dall Tube PRESO Low Loss Tube Diameter Ratio, ß Permanent heat loss as function of diameter ratio Reduced Pumping Cost Low permanent pressure loss gives user significant savings. A low-loss tube frequently pays for itself in 6-8 months of continuous use. Installation 1. The primary station can be installed in any position on vertical or horizontal lines. However on horizontal liquid lines where the risk of air/gas entrapment in the meter tubing is prevalent. Install the element with the connections on or near the side below the horizontal center line. For horizontal air or gas lines, install the element with the connections on or near the side above the horizontal centerline.. Install so that the flow arrow or the indicated inlet is the correct direction of flow. 3. Location Instructions: A B Elbows in Same Plane Two Elbows Not in Same Plane Wide Open Gate Valve Reducer Expander Partially Throttled Gate Valve Globe Valve Check Valve Diameter Ratio, ß Different Fittings; ASME Recommendations Typical Low-Loss Specifications Furnish and install PRESO Venturi Flow Elements where shown on plans and drawings as manufactured by Preso Meters Corp. Each sensor shall be a modified Venturi type of the Low-Loss design producing a differential pressure between the inlet and throat section which is proportional to the square of flow rate through the tube. The inlet section shall be of similar diameter as the internal dimension of the pipe followed by a contoured radius which will cause a uniform change of fluid velocity. The exit cone shall be angled precisely to the manufacturers standards in order to prevent a permanent pressure loss exceeding 6% of the differential pressure. Accuracey shall be within +1% over a 10:1 range Washington Ave., Racine, WI Tel.: (6) Fax: (6) Toll Free: (800) info@preso.com Venturi Rev

VERIS Accelabar. Superior Flow Measurement Accuracy

VERIS Accelabar. Superior Flow Measurement Accuracy VERIS Superior Flow Measurement Accuracy Designs, materials, weights and performance ratings are approximate and subject to change without notice. Visit for up-to-date information. ...A New Idea in Flow