OD Vs Nominal Pipe Size

Tubing vs. Pipe Sizes 


The terms tubing and pipe can often mistakenly be combined with each other causing confusion during the quoting and ordering processes.  Please see the following conversion chart showing the electric resistance welded steel tubing OD sizes and wall thicknesses that Valmont Tubing produces that match the corresponding nominal pipe sizes (NPS) in schedule 5, 10, 40 and 80 wall thicknesses.  These nominal pipe sizes are most often associated with ASTM specifications A53 and A135.
 
 
Pipe Size Tubing OD
(Inches) 
Sch. 5 
Wall Thickness
Sch. 10
Wall Thickness 
Sch. 40
Wall Thickness 
Sch. 80
Wall Thickness 
 3/4 Inch NPS 1.05 .065 in  .083 in  .109 in  .156 in 
 1 Inch NPS 1.312  .065 in  .109 in .134 in .180 in 
 1 1/4 Inch NPS 1.66 .065 in  .109 in .148 in  .188 in 
 1 1/2 Inch NPS 1.90 .065 in  .109 in  .148 in  .203 in 
 2 Inch NPS 2.375 .065 in  .109 in  .156 in  .220 in 
 2 1/2 Inch NPS 2.875 .083 in  .120 in  .203 in   
 3 Inch NPS 3.50 .083 in  .120 in  .220 in   
 3 1/2 Inch NPS 4.00 .083 in  .120 in  .220 in   
 4 Inch NPS 4.50 .083 in  .120 in  .238 in   
 4 1/2 Inch NPS 5.00     .250 in   
 5 Inch NPS 5.563 .109 in  .134 in  .250 in   
 6 Inch NPS 6.625 .109 in  .134 in  .280 in   
 8 Inch NPS 8.625 .109 in  .148 in  .312 in   
 10 Inch NPS 10.75 .134 in  .165 in     
 12 Inch NPS 12.75 .165 in  .180 in     
NOTE:  Under ASTM specifications A53 and A135, pipe having other dimensions may be furnished provided that the pipe complies with all other requirements of those specifications.  Consequently, Valmont is able to certify other OD sizes to those specifications as well if required.                          

Tubing provides more precise measurements for the outside diameter, inside diameter, wall thickness, chemistries and length than pipe specifications.  In addition, a greater number of OD sizes are available to select from leading to easier fit, fabrication and formability for end users. For a complete listing of tubing sizes that Valmont produces, please visit our Steel Tubing Product Catalog.