Dwyer 166T – 11.5″ to 36″ Telescoping Stainless Steel Pitot Tube

• Telescoping pitot tube senses airflow in ducts
• Device length extends from 11.5″ to 40.5″/30 to 103 cm
• Sections lock in place to ensure correct alignment of the tip within the airstream
• Stainless steel construction resists corrosion
• Hemispherical tip has 1.0 flow coefficient and 1/8″ diameter

The Dwyer 166T Telescoping Stainless Steel Pitot Tube is a unique air flow sensor which can quickly and easily be adjusted for any duct insertion length from 11.5 to 36 inches (29.2 to 91.4 cm), allowing it to replace up to 5 conventional fixed length Pitot tubes. The telescoping sections lock in place as they are extended, which enables the use of the handheld grip to gauge proper alignment of the tip with the airstream. For even greater convenience, it is securely protected by a custom fitted polyethylene carrying case.

The Model 166T Telescoping Pitot Tube is a convenient adjustable length instrument for sensing air flow in a wide range of duct sizes, extending your reach to 36 inches (91 cm). It is ideal for almost any air velocity measurement where permanent mounting is not required. Because of the very small sensing holes on the tip, flow must be reasonably clean and free from particulates which could cause blockage.

The Model 166T consists of a standard 1/8 ̋ diameter Pilot tube attached to a four-section stainless steel telescoping tube and a comfortable hand grip designed for ease in maintaining proper orientation. This device can be used at any length from 11 15 / 32 ̋ to 40 7 / 16 ̋ (30 to 103 cm). A 3/8 ̋ (9.5 mm) diameter hole is required for full insertion. For maximum accuracy, the 1/8 ̋ diameter tip should be always be extended to its full 3 ̋ length regard- less of how far the telescopic sections are extended.

While extending the tip, twist it slowly back and forth until you feel it engage with the end of the first telescoping section. Next, extend the Model 166T to the required length and rotate the telescoping sections to align the tip so it points in the same direction as the finger grips on the handle. See drawings. Now when unit is inserted in the duct, you can refer to the handle orientation as a guide to assuring the tip is pointing into the airstream as required for best accuracy.

When extending or collapsing the telescopic tube, be sure the flexible rubber tubing moves freely through the opening in the end of the handle. The pressure connections on the terminal block are marked “S” for static pressure and “T” for total pres- sure. Connect the static pressure to the minus (-) or low pres- sure port on the manometer or gage and the total pressure to the positive (+) or high pressure port. See Dwyer Instruments, Inc. full line catalog for complete air flow measuring instructions, for- mulas and flow curves.