- No calibration needed
- Precisely located, burr-free static pressure holes
- Hemispherical tip design, best for accuracy if imperfectly aligned and nearly impossible to damage
- Long lasting 304 SS construction
- Silver soldered connections for leak-proof operation
- Coefficient of “1”
- 5/16˝ models rated to 1500°F
- Extended static connection helps guide tip within recommended 15° of air flow direction
- Inch graduations on sides of 160 series to quickly determine exact insertion depth
- Dwyer® Air Velocity Calculator, direct reading flow charts and instructions included
- Use 1/8˝ models in ducts as small as 4˝, 5/16˝ models in ducts 10˝ or larger
- Optional mounting gland or split flange make permanent installation fast and simple
Series 160 Stainless Steel Pitot Tube
The Dwyer 160 Series stainless steel pitot tubes are designed for use with differential pressure transmitters, manometers, or air velocity gauges to measure air flow in ducts. See Measuring Air Flow in the Technical Reference Section for complete application information.
The 160 Series is designed per ASME and meets AMCA and ASHRAE standards. Insertion depth is stamped on the side of the pitot tubes, and the static pressure port is parallel to the sensing tube to allow easy alignment with air flow. A Model A-158 split flange mounting kit allows for simple, leak-free mounting of the 160 Series.
The SERIES 160 Stainless Steel Pitot Tube is constructed from corrosion resistant stainless steel with permanently etched insertion depth graduations for a lifetime of service. The static pressure port is parallel to the sensing tube to allow quick, easy alignment of the tube with air flow. A universal model fits the user supplied 3/4" schedule 40 pipe in any length.
Ideal for use with our precision manometers and air velocity gages, Dwyer® Pitot Tubes are constructed from corrosion resistant stainless steel for a lifetime of service. ASME design meets AMCA and ASHRAE specifications for maximum accuracy over a wide variety of flow conditions. No correction factors required as ASHRAE tip design yields a calibration factor of 1. ASHRAE design needs no calibration!
Permanent, stamped insertion depth graduations on sides of 160 series facilitate accurate positioning. Static pressure port is parallel to sensing tube allowing quick, easy alignment of tube with air flow. Low sensitivity to misalignment gives accurate reading even when tube is misaligned up to 15 degrees.
Various standard sizes are available for use in ducts as small as 4˝ dia, or as large as 36 ft dia. A universal model fits user supplied 3/4˝ schedule 40 (standard) pipe in any length. Several convenient mounting options are available for permanent installations.
Monitor or control static or differential pressure when combined with differential pressure gage, switch or transmitter.
Installation and Operating Instructions
The total pressure of an air stream flowing in a duct is the sum of the static or bursting pressure exerted upon the sidewalls of the duct and the impact or velocity pressure of the moving air. Through the use of a pitot tube connected differentially to a manometer, the velocity pressure alone is indicated and the corresponding air velocity determined.
For accuracy of plus or minus 2%, as in laboratory applications, extreme care is required and the following precautions should be observed:
- Duct diameter to be 30 times pitot tube diameter, or greater.
- Make an accurate traverse per sketch at right, calculate the velocities and average the readings.
- Provide smooth, straight duct sections a minimum of 8 1/2 diameters in length upstream and 1 1/2 diameters down stream from the pitot tube.
- Provide an egg crate type straightener upstream from the pitot tube.
In making an air velocity check select a location as suggested above, connect tubing leads from both pitot tube connections to the manometer and insert in the duct with the tip directed into the air stream. If the manometer shows a minus indication reverse the tubes. With a direct reading manometer, air velocities will now be shown in feet per minute.
In other types, the manometer will read velocity pressure in inches of water and the corresponding velocity will be found from the curves in this bulletin. If circumstances do not permit an accurate traverse, center the pitot tube in the duct, determine the center velocity and multiply by a factor of .9 for the approximate average velocity. Field tests run in this manner should be accurate within plus or minus 5%.
AIR VELOCITY CALCULATOR
Computes velocity based on air density corrected for conditions of temperature and pressure. Eliminates tedious calculations. Ranges from .01 to 10˝ water corresponding to 400 to 20,000 FPM. Furnished with each pitot tube.
STAINLESS STEEL PITOT TUBES
Test confirmed unity coefficient and lifetime construction of No. 304 stainless steel. Inch graduations show depth of insertion for traversing. Model 160 is designed to meet ASME “Fluid Meters” 6th Ed, ANSI/AMCA 210- 99, ANSI/ASHRAE 51-1999, and British Standard 1042. Sizes 12˝ to 60˝ long. Hand or fixed mounting types.