Round pipes known as schedules are virtually the same as any other type of pipe; however, schedules have a number, which will define the thickness of the tube depending on its diameter.
There is no official consensus on the origin of the schedule pipe, but one of the most accepted versions is that the term began to be used during the industrial revolution. This corresponded to a standard created in the United States to ensure that a tube could withstand a certain vapor pressure. For this reason, a Schedule 30 supported less pressure than a Schedule 40.
Back then, the pipes used to conduct steam from machines were made of cast iron. As there were not as many metal alloys as we have today, the only way to make a tube more resistant to pressure was by making the tube wall thicker. For this reason, a Schedule 80 pipe had to withstand greater pressure and therefore had to have an iron wall that was thicker than a Schedule 40 pipe.
With the passing of time, the use of steel for the production of pipe was industrialized, but the nominal standards of the schedules remained as a convention in the industry.
To better understand this, we share this example: A schedule 30 with a nominal diameter of 2” has a wall thickness of 0.1046″; while, for the same nominal diameter of pipe, but in a schedule 80, the wall thickness will be 0.2160 “.
You can see this example clearer in the following table:
|Schedule||Nominal diameter||Wall thickness|
Finally, although it is easy to remember that the higher the schedule number, the thicker the tube will be; the best way to know exactly the relationship between the nominal diameter of the pipe, the schedule number and the wall thicknesses; It is by reviewing our conversion tables, which you can find in our product catalog.
Ask your sales represantive for availability in different lengths and thicknesses.