Standard dimension ratio sdr is a method of rating a pipe s durability against pressure.
Sdr pvc pipe meaning.
A higher sdr means a lesser pipe thickness with a lesser pressure rating.
Sdr for a 10 inches astm d2241 pvc pipe with outside diameter 10 750 inches and wall thickness 0 168 inches can be calculated as.
The series is a geometric progression where each sdr is approximately 25 higher than its predecessor.
With a high sdr ratio the pipe wall is thin compared to the pipe diameter.
The sdr is the ratio of pipe diameter to wall thickness and the sdr can be expressed as.
An sdr 11 means that the outside diameter od of the pipe is eleven times the thickness of the wall.
They are highly resilient with high tensile and high impact strength.
Therefore a higher sdr indicates a thinner walled pipe at any given diameter.
Sdrs are a series of preferred numbers known as renard numbers.
Pvc pr 160 pr 200 and pr 315 are for pressure systems where temperatures will not exceed 140 f.
Pipes with a lower sdr can withstand higher pressures.
The sdr pipe is the standard dimensional ratio and refers to the geometry of the pipe.
Nominal pipe size in o d.
Sdr is defined as the ratio of the nominal outside diameter to the nominal wall thickness.
The standard dimension ratio describes the correlation between the pipe dimension and the thickness of the pipe wall.
For pvc pipe sdrs start at 13 5 and include 17 21 26 32 5 41 51 and 64.
Common nominations are sdr11 sdr17 and sdr35.
Where dn is the nominal outside diameter of the pipe and en is the nominal minimum wall thickness of the pipe.
With a low sdr ratio the pipe wall is thick compared to the pipe diameter.
Standard dimension ratio sdr the ratio of pipe diameter to wall thickness sdr d s d pipe outside diameter mm in s pipe wall thickness mm in sdr 26 diameter d is 26 times the wall thickness s thus rated pressure is higher for low sdr ratios and lowwer for higher sdr ratios.
D pipe outside diameter mm in s pipe wall thickness mm in example sdr.
A lower sdr means a higher pipe thickness with lower pressure rating.
The terms dimension ratio and standard dimension ratio are widely used in the pvc pipe industry.
So a high sdr pipe has a low pressure rating and low sdr pipe has a high pressure rating.
Both terms refer to the same ratio which is a dimensionless term that is obtained by dividing the average outside diameter of the pipe by the minimum pipe wall thickness.
