TDD Direct Drive Tubeaxial In-line Duct Fan

Tubeaxial Fan Series

TDD Models

Model Features

  • Rated up to 39,194 CFM in static pressure applications up to 1-1/4" w.g.
  • Direct drive units have low sound levels and quiet operation
  • Smaller sizes for areas with reduced airflow needs
  • Require practically no maintenance
  • cULus 705 Listed
  • AMCA Air Licensed
  • This product meets the requirements of Buy American (2009) and Build America, Buy America (BABA), as part of IIJA (2022). Download letter here.

AMCA Air cULus   BABA-ACT

Model Overview

The Tubeaxial line offers the widest range of sizes, horsepower, and performance in the industry. TDD's are high capacity tubeaxial fans rated from 643 to 39,194 CFM, with static pressure capability up to 1-1/4". They are used to exhaust air from or supply air to commercial and industrial applications, such as general building ventilation, enclosed garages, and other applications where the air is moved through a duct system against moderate static pressure.

TDD's are best used for exhausting or supplying relatively clean ambient temperature air. They require practically no maintenance and are available in smaller sizes for areas with reduced airflow needs.

2-year fan housing warranty, 1-year motor warranty

Size CFM Range Max SP
12 816 to 1,507 1/8"
16 1,889 to 3,240 1/2"
18 2,525 to 5,226 5/8"
20 643 to 4,777 3/4"
24 2,640 to 9,585 1"
30 1,559 to 15,387 1-1/4"
34 4,043 to 26,099 1-1/4"
36 2,562 to 26,845 1-1/4"
42 3,561 to 32,213 1-1/4"
48 8,730 to 39,194 1"
Dimensional Drawing for the TDB Model

Dimensional data is displayed in inches.

Size A B C1 B.C.D.
12 12-3/8 15 12 13-1/2
16 16-3/8 18-7/8 16-1/2 17-3/8
18 18-3/8 22-1/2 22 19-3/4
20 20-3/8 24-1/2 22 21-3/4
24 24-3/8 28-5/8 23 25-3/4
30 30-3/8 34-5/8 24 32
34 34-3/8 38-5/8 27 36-3/8
36 36-3/8 40-58 29 38
42 42-1/2 46-3/4 30 44-1/4
48 48-1/2 52-3/4 33 50-3/4

1. The motor may extend past unit size.

Additional accessories are available for certain products. Contact your S&P Representative for more information about these accessories.

Standard Accessories

Motor Cover  
Belt Guard  
Hanging and Floor Brackets  
Companion Flange (Inlet/Outlet)  
Inlet Guard  
Outlet Guard  
Mounting Rails  
Rubber Isolator  
Spring Isolator  
Inspection Door  
Disconnect Switches  
Shaft Seal  

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General Catalog Section PreviewDownload
Typical Specification Sheet PreviewDownload
Submittal PreviewDownload
IOM PreviewDownload
Mounting Diagram PreviewDownload

TDD Download

  • General/Clean Air
  • Contaminated Air
  • Spark Resistant