What is the outer diameter size of each nominal diameter of the pipe?

There are two kinds of pipe nominal diameter annotation methods, one is the outer diameter is the nominal diameter, the outer diameter = nominal diameter, the other is the nominal diameter with the inner diameter, and then the pipe wall thickness has different specifications, therefore, the pipe outside the annotation method depends on different specifications, outer diameter = inner diameter (nominal diameter) pipe wall thickness 2 examples of galvanized pipe wall thickness specifications, nominal 15mm outer diameter = 20mm, 20mm outer diameter = 25mm....

Its nominal diameter is not the outer diameter or the inner diameter, but a nominal size approximating the inner diameter of ordinary steel pipes. Each nominal diameter corresponds to an outer diameter, and its inner diameter value varies with the thickness. The nominal diameter can be expressed in metric mm

Standard Specifications for Pressure Piping.

dn - nominal diameter.

Outer Diameter Large Outer Diameter Series DN15- 22mm, DN20- 27mmDN25- 34mm, DN32- 42mmDN40- 48mm, DN50- 60mmDN65- 76(73)mm, DN80- 89mmDN100- 114mm, DN125- 140mmDN150- 168mm, DN200- 219mmDN250- 273mm, DN300- 324mmDN350- 360mm, DN400- 406mmDN450- 457mm, DN500- 508mmDN600- 610mm, small outer diameter series.

dn15-ф18mm，dn20-ф25mmdn25-ф32mm，dn32-ф38mmdn40-ф45mm，dn50-ф57mmdn65-ф73mm，dn80-ф89mmdn100-ф108mm，dn125-ф133mmdn150-ф159mm，dn200-ф219mmdn250-ф273mm，dn300-ф325mmdn350-ф377mm，dn400-ф426mmdn450-ф480mm，dn500-ф530mmdn600-ф630mm，

Pipe diameter size refers to the average value of the outer diameter of the pipe and the inner diameter of the pipe.

Generally speaking, the diameter of the tube can be divided into outer diameter, inner diameter, and nominal diameter. The outer diameter of the pipe is represented by the letter D, followed by the size and wall thickness of the outer diameter, for example, the wall thickness of the seamless steel pipe with an outer diameter of 108 is 5mm, which is represented by D108*5.

Plastic pipes are also represented by outer diameter, such as DE63, others such as reinforced concrete pipes, cast iron pipes, galvanized steel pipes, etc. are represented by DN, and the nominal diameter is generally expressed in the design drawings, and the nominal diameter is a standard artificially specified for the convenience of design, manufacturing and maintenance, also known as the nominal diameter, which is the specification name of the pipe (or pipe fittings).

The pipe diameter size is the "nominal diameter".

The nominal diameter is the size of all the piping accessories in the piping system expressed by numbers, and the nominal diameter is a convenient round integer for reference, which is only not strictly related to the processing size. Nominal diameter is written in letters"dn"This is followed by a digital sign.

Nominal diameter, also known as mean outside diameter.

This is due to the fact that the pipe is very thin from the metal pipe, and the outer diameter of the pipe is almost the same as the inner diameter of the pipe, so the average value of the outer diameter of the pipe and the inner diameter of the pipe is taken as the pipe diameter.

For example, a pipe with a diameter of 15 corresponds to various types of pipes with an outer diameter of 22 or 20 (wall thickness of ,,,, etc.), where the diameter often refers to a certain range of pipes, rather than the average of the outer diameter and the inner diameter.

Denotes the outer diameter and DN denotes the inner diameter.

DN refers to the nominal diameter of the pipe, which is neither the outer diameter nor the inner diameter, but a nominal size approximating the inner diameter of an ordinary steel pipe.

For containers, the nominal diameter is expressed as the inner diameter; For pipes, it is expressed as a size smaller than the outer diameter and larger than the inner diameter. Corresponding to a certain nominal diameter of the pipe, its outer diameter is a certain value, and the inner diameter varies with the wall thickness.

The nominal diameter can be expressed in the metric system mm or in the imperial system.

Pipe diameter: When the pipe wall is relatively thin, and the inner diameter is large, and the outer diameter of the pipe is almost the same as the inner diameter of the pipe, the average value of the outer diameter and the inner diameter of the pipe is called the "pipe diameter". That is, the name of the pipe diameter ignores the wall thickness.

Due to the different materials and uses of the pipes, the thickness of the pipe wall is different, when the pipe wall is thicker and the inner diameter is smaller, the inner diameter can only be calculated instead of the pipe diameter.

The inner diameter is simple to calculate, with an outer diameter of 2e (wall thickness). Taking cast iron drainage pipe as an example, the wall thickness of 140 cast iron pipe is generally, then, its inner diameter is 140

The outer diameter of the pipe 140 corresponds to the pipe diameter DN125.

Summary. The expression of the pipe diameter shall comply with the following provisions:

1. The diameter of water gas transmission steel pipes (galvanized or non-galvanized), cast iron pipes and other pipes should be expressed by the nominal diameter DN;

2. Seamless steel pipes, welded steel pipes (straight seams or spiral seams), copper pipes, stainless steel pipes and other pipes, the pipe diameter should be expressed by the outer diameter wall thickness;

3. Reinforced concrete (or concrete) pipes, clay pipes, acid-resistant ceramic pipes, cylinder tile pipes and other pipes, the pipe diameter should be represented by the inner diameter d;

4. For plastic pipes, the diameter of the pipe should be expressed according to the method of product standards;

5. When the design uses the nominal diameter dn to represent the pipe diameter, there should be a comparison table between the nominal diameter dn and the corresponding product specifications. The specifications of rigid PVC pipes for building drainage are represented by DE (nominal outer diameter) E (nominal wall thickness) (GB), and the specifications of polypropylene (PP) pipes for water supply are represented by DE E (nominal outer diameter and wall thickness).

Pipe diameter size refers to the outer or inner diameter.

Pipe diameter size refers to the inner diameter.

If not stated, it refers to the inner diameter.

For example, a two-inch pipe refers to a pipe with an inner diameter of 50 mm, and a four-inch pipe refers to a pipe with an inner diameter of 15 mm. It is mainly divided into 4 points, 6 points, 1 inch, 1 inch 2, 1 inch and a half and so on, and its pipe diameter will change accordingly.

dn15 ，dn20 ，dn25 ，dn32 ，dn40 ，dn50 。

200mpp pipe. Whether it's an outer diameter or an inside diameter.

The expression of the pipe diameter shall comply with the following provisions: 1. The diameter of the pipe should be expressed in the nominal diameter of the water gas transmission steel pipe (galvanized or non-galvanized), cast iron pipe and other pipes; 2. Seamless steel pipes, welded steel pipes (straight seams or spiral seams), copper pipes, stainless steel pipes and other pipes, the pipe diameter should be expressed by the outer diameter wall thickness; 3. Reinforced concrete (or concrete) pipes, clay pipes, acid-resistant ceramic pipes, cylinder tile pipes and other pipes, the pipe diameter should be represented by the inner diameter d; 4. For plastic pipes, the diameter of the pipe should be expressed according to the method of product standards; 5. When the design uses the nominal diameter dn to represent the pipe diameter, there should be a comparison table between the nominal diameter dn and the corresponding product specifications. The specifications of rigid PVC pipes for building drainage are represented by DE (nominal outer diameter) E (nominal wall thickness) (GB), and the specifications of polypropylene (PP) pipes for water supply are represented by DE E (nominal outer diameter and wall thickness).

200mpp pipe. It is the inside diameter size.

Okay thank you. You're welcome <>

The comparison table between the nominal diameter and the outer diameter of the seamless steel pipe is as follows:

The production process of general seamless steel pipe is divided into two types: cold-rolled and hot-rolled, and the appearance of cold-rolled seamless steel pipe is shorter than that of hot-rolled seamless steel pipe, and the wall thickness of cold-rolled seamless steel pipe is generally smaller than that of hot-rolled seamless steel pipe. But the surface looks brighter than the thick-walled seamless steel pipe headrock. There isn't too much roughness on the surface and not too many burrs on the caliber.

The maximum nominal diameter of cold-rolled pipes is 200 mm, and the maximum nominal diameter of hot-rolled pipes is 600 mm.

The nominal diameter of a steel pipe (DN) refers to the standard size of the pipe, which is usually measured in millimeters (mm). The nominal wall thickness (WT) of the tube corresponds to the nominal wall thickness (WT), which is also usually measured in millimeters.

The outside diameter (OD) of a steel pipe refers to the size of the outer diameter of the steel pipe, which is usually also measured in millimeters. The pre-trap corresponding to the outer diameter is the wall thickness (W) of the tube, which is also usually measured in millimeters.

In the standard specifications of steel pipes, the nominal diameter and outer diameter correspond to each other, and the comparison between them usually varies according to the material and use scenario of the steel pipe. For example, the nominal diameter and outer diameter comparison table of commonly used carbon steel pipe and stainless steel pipe are as follows:

Nominal diameter (dn) |Outer Diameter (OD) |

It should be noted that the nominal diameter and outer diameter of the steel pipe are only standard specifications, and there may be certain deviations in the actual production of the steel pipe, so it is necessary to make actual measurements and select the appropriate pipe according to the actual situation when selecting and using the steel pipe.