Mainly largediameter pipes used in the construction of oil pipelines, gas pipelines, heating systems and sewage. Large diameter pipes are, as a rule, the main pipe with external diameter Ø mm. 1141420 in the installation of engineering systems and communications experts are often faced with the problem of calculation of pipes diameter Ø 114 mm and above. Since most types and sizes of pipe insulation based on polymers at the end diameters Ø114133 mm, the design and installation manufacturers propose to use variations of thermal insulation in rolls, pads or cylinders.
Depending on the purpose of the pipes is chosen the type of insulation material with appropriate parameters (thickness, density, coating). As a rule, engineering services, heating systems, water, sewer pipework laid underground, it is important to choose the insulation material to adhere to the technology installation. In this article we will understand how to select the insulation thickness for pipes of large diameter and how to calculate the necessary quantity of insulation sheet, according to set parameters –length of the pipeline and the thickness of the insulation, where the diameter of the pipeline exceeds the available market sizes of pipe insulation.
Mainly for the insulation of large diameter pipes used sheet materials of polymers, spray polyurethane foam insulation or mineral wool. The company "Sanpreis" offers the following types of insulation pipes of larger diameter:
Example: let's look at an example of how to choose the thickness of the insulation of the pipeline. For example, we need to insulated steel pipe with an outer diameter of Ø300 mm and with an operating temperature of 250°C. Select the value according to table 1, "Selection of thickness of thermal insulation on the basis of mats and cylinders of mineral wool depending on the diameter of the pipe and temperature". So, when the given parameters we get the value 100 mm. That is for pipe with diameter Ø300 mm and temperature media 250°C, we need the insulation of basalt cylinders or mats of mineral wool of thickness not less than 100 mm.
The selection of the thickness of insulation on the basis of mats and cylinders of mineral wool depending on the diameter(Ø100450 mm) tubing and temperature
table 1
Diameter, mm 
Insulation thickness, mm cylinder and mats made of mineral wool depending on the working temperature °C pipe 


100 
150 
200 
250 
300 
350 
400 
450 
100 
30 
40 
75 
80 
100 
115 
145 
160 
150 
40 
50 
75 
80 
115 
120 
150 
175 
200 
40 
50 
75 
90 
115 
125 
160 
180 
250 
40 
50 
75 
90 
120 
130 
170 
190 
300 
40 
50 
75 
100 
125 
140 
180 
200 
350 
50 
50 
75 
100 
125 
150 
190 
210 
400 
50 
60 
75 
115 
125 
150 
190 
210 
450 
50 
60 
85 
120 
140 
160 
200 
220 
For the insulation of large diameter pipes, you can use the cut according to the required dimensions of the sheet material.
Example: pipe insulation of foam rubber ends on the diameter Ø114 mm. And we need to insulate steel pipe with outer diameter Ø133 mm and a thickness of the insulating layer is 19mm. How to do it?
If you want to isolate a larger diameter pipe that is above Ø114 mm, using in this case the sheet material. How to calculate the required number of sheet material m^{2}, if there is only the outer diameter and length of the pipeline. Select the value using table 2 or calculate yourself using the formula of recalculation of the insulation sheet. Thus, according to table 2, we get the value 0.48 m^{2}. That is, to isolate 1 of M. p. steel pipes with outer diameter Ø133 mm and a thickness of the insulation is 19 mm, we will need a 0.48 m^{2} sheet of insulation made of foam rubber.
In the first and in the second case, we obtain the required number of sheet material m^{2 }to isolate 1 of M. p. in the pipeline.
For convenience calculate the number of sheet insulation for pipes of large dimensions (Ø114325 mm), experts have developed table 2:
table 2
The translation table sheet insulation for large diameter pipes (m^{2} in M. p. ) 

Steel pipe 
The thickness of the insulation 

Size in inches 
External diameter, mm 
DU, conditional pass, mm 
6 mm 
9 mm 
13 mm 
19 mm 
25 mm 
32 mm 
50 mm 
4 
114 
100 
0,38 
0,39 
0,40 
0,42 
0,44 
0,46 
0,52 

133 

0,44 
0,45 
0,46 
0,48 
0,50 
0,52 
0,58 
5 
140 
125 
0,46 
0,47 
0,48 
0,50 
0,52 
0,54 
0,60 
6 
160 

0,54 
0,55 
0,56 
0,58 
0,60 
0,62 
0,68 
6 1/2 
180 
160 
0,59 
0,60 
0,61 
0,63 
0,65 
0,67 
0,73 
8 
219 
200 
0,71 
0,72 
0,73 
0,75 
0,77 
0,79 
0,85 
10 
273 
250 
0,88 
0,89 
0,90 
0,92 
0,94 
0,96 
1,02 
12 
325 
300 
1,05 
1,06 
Of 1.07 
Of 1.09 
1,11 
1,13 
1,19 
To calculate the amount of material for pipe insulation sheet (rolls) material, you must have two parameters:
The calculation of the thickness of the insulation of large diameter pipes can be produced using the formula of conversion of number of isolation of M. p. in m^{2}:
Formula recalculation sheet of insulation m^{2 }= Øduct*π *hpipeline/1000
where:
Øtubing– outer diameter of pipe (mm)
hpipeline – the pipeline length (M. p.)
As a result of calculation we get m^{2 } required quantity of sheet material on 1 linear meter of the pipeline.
Example: tube with diameter of 300mm and the required insulation thickness to 19mm at the piping length of 50m, calculate the required number of sheet: (300 19 19)*3,14/1000 * 50m = approximately 54 sq. m sheet of the insulation necessary to isolate pipes.
The company's products "Sanpreis" has the quality certificates and other permits, and meets the basic criteria when choosing insulation for large diameter pipes.
Solutions with the correct materials, operate throughout the life of the equipment, while retaining its characteristics. Please contact us, we will help you select insulation material and to make the miscalculation of tubing of any diameter