Solve it – what does sch20 mean in the diagram?
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In the diagram, for each nominal diameter, there are wall thickness values of sch20, 30, 40, with the maximum value being 160; there is also a xxs option. What do all these mean? Please provide a detailed explanation. Thank you everyone
Sch is a code indicating the wall thickness; for example, the wall thickness of DN50 sch20 is T=3.5mm. XXS is also a code for wall thickness.
Generally, the wall thickness is first calculated based on temperature, pressure, and corrosion allowances; the resulting value represents a specific thickness. This value is then matched to a corresponding thickness designation from a table. The SCH designations are established in order to standardize the wall thickness requirements for similar pipelines as much as possible, by choosing values that are as high as feasible, thereby enabling steel manufacturers to produce in bulk and reduce the number of different specifications needed.
There are three ways to indicate the wall thickness of steel pipes: the pipe designation, the wall thickness dimension, and the pipe weight. 1) The wall thickness is indicated by the pipe designation “Sch”. Pipe designation number: It is the value obtained by multiplying the ratio of the design pressure to the allowable stress of the material at the design temperature by 1000, and then rounding it off. That is: Sch＝P/t×1000. ANSI B36.10 wall thickness grades include ten levels: Sch10, Sch20, Sch30, Sch40, Sch60, Sch80, Sch100, Sch120, Sch140, Sch160; ANSI B36.19 wall thickness grades include four levels: Sch5s, Sch10s, Sch40s, Sch80s. 2) It is expressed in terms of the pipe wall thickness; some Chinese, ISO, and Japanese pipe standards use this method. 3) The wall thickness is indicated by the weight of the pipe, with three categories: a. Standard weight pipes, denoted as STD; b. Thickened pipes, denoted as XS; c. Extra-thick pipes, denoted as XXS. For pipes with DN≤250mn, Sch40 is equivalent to STD, DN
Wall thickness grade code; refer to ANSI B36.10/ASME B36.10M
The method for indicating the wall thickness of steel pipes can be found in the table above: lol
For example, for a 1-inch pipe, how can I determine its thickness, and what SCH value corresponds to it?
This is calculated based on the specific medium being transported; the resulting value is then applied to the corresponding SCH value. For the calculation formula, refer to SH T3059 or the formulas for calculating steel pipe wall thickness outlined in GB 50316 standards
It is a code for wall thickness; it is explained in the pipeline specifications