Sdr Plastic Pipe Meaning

Many plastic pipe manufacturers use the standard dimension ratio sdr method of rating pressure piping.

Sdr plastic pipe meaning.

Even though the terms dr and sdr are synonymous one minor difference between them is that sdr refers only to a particular series of numbers i e 51 41 32 5 26 21 etc. Standard dimensions ratio sdr. S p dn en. Solvent cemented fittings are commercially available to connect pipes based on inches to those based on millimeters.

Therefore a higher sdr indicates a thinner walled pipe at any given diameter. Additional considerations for pvc pipe and dr a pvc pipe with a higher dr has a thinner wall. Dr and sdr are identical. Sdr d s 1 where.

The sdr is the ratio of pipe diameter to wall thickness and the sdr can be expressed as. 1 2 t pipe minimum wall thickness in 5 pipe diameter for id controlled pipe standards for inside diameter controlled pipes provide average dimensions for the pipe inside diameter that are used for flow calculations. With a low sdr ratio the pipe wall is thick compared to the pipe diameter. With a high sdr ratio the pipe wall is thin compared to the pipe diameter.

This entry deals with the inch based sizes of pvc pipe in use in the united states. The relationship between the sdr and the pressure rating is given by lames formula for the hoop stress in thick wall cylinders. Nominal pipe size average outside diameter minimum wall thickness in and calculated id in in in sdr 64 sdr 41 sdr 32 5 sdr 26 sdr 21 sdr 17 sdr 13 5 wall id wall id wall id wall id wall id wall id wall id 1 8 0 405 0 06 0 35 1 4 0 54 0 06. The standard dimension ratio describes the correlation between the pipe dimension and the thickness of the pipe wall.

Metric pvc pipe sizes have an entry of their own what americans call pvc is called pvc u in europe and cpvc is called pvc c. This means that as dr increases the pipe will have less pressure capacity and lower pipe stiffness. In other words for a given dr or sdr pressure capacity and pipe stiffness remain constant regardless of pipe size. Common nominations are sdr11 sdr17 and sdr35.

Standard dimension ratio sdr is a method of rating a pipe s durability against pressure. Strengths weaknesses of plastic pipes. So a high sdr pipe has a low pressure rating and low sdr pipe has a high pressure rating. A pipe average inside diameter in d o pipe outside diameter in dr dimension ratio dr t do eq.

Pipes with a lower sdr can withstand higher pressures. An sdr 11 means that the outside diameter od of the pipe is eleven times the thickness of the wall. One easy way to tell abs and pvc apart is that abs pipes are black and pvc pipes are white. Where dn is the nominal outside diameter of the pipe and en is the nominal minimum wall thickness of the pipe.

By definition dr is applicable only to solid wall pipe and has no relevance for profile wall products. For example pvc is more flexible but abs is stronger and more shock resistant.