program
Výrobní program O firmě Certifikáty Ceník Kontakty
1. Pre-insulated Pipeline Systems
Introduction – General Information
Applied Materials
Medium-Conducting Pipeline
Insulating Layers
Outer Protective Layers
Pipeline and Fittings
PIP 130 A, B, C
PIP 180 A, B, C
PIP 210, 240, 270
PIP 300 A, B, C
Elbows, Branches, Reducers, Compensators, Fixed Points
Accessory Parts - Entries, Pipeline Ends, Expansion Cushions
Mounting Instructions for Pipeline Connection, Coupling Design
Safety Regulations
Handling, Storage
Planning Activity Documents
Earth Works
Thermal Losses of Distribution Systems – k-Coefficient
Heat Dilatation PIP
Solution of Heat Dilatation
Compensating Bodies L, Z, U
Heat Tensioning of Pipeline
Axial Compensators
Steam Distribution System
Monitoring System
2. Production Assortment of the Company IZO

Installation Length

The pre-insulated pipeline system PIP 130 represents a compact unit, it means that the medium-conducting pipe, polyurethane insulating layer and outer protective coat forms one unit that moves in sand bedding as a result of temperature effect.

The arisen friction force is calculated by means of the formula:

Fft = ft . ρz . g . h . π . DPE       [Nm-1]

where:  ft  -  friction coefficient between HD-PE and sand bedding [0,2 - 0,6]
ρz  -  volume weight of the backfill [1800 - 2200 kg.m-3]
g  -  gravity acceleration [9,81 ms-2]
h  -  height of the covering layer from the pipeline axis [m]
DPE  -  outer protection pipe diameter [m]

In the course operation, there occurs dilatation movement of the pipeline in the sand bedding as a result of temperature changes. This movement is limited by friction. Consequence of this movement limitation is rise of stress in the medium-conducting pipeline, this stress increases in proportion to the installed length.

Not to exceed the allowed stress, it is necessary to respect the so-called installing length from the viewpoint of operating parameters.

Li = 
A . σdov

Fft
        [m] 
where:  Li  =  maximum installation length [m]
A  =  cross section of the steel pipeline [mm2]
σdov  =  allowable axial stress of steel - 120 - 140 [N.mm-2]
Fft  =  friction force [N.m-1]

To prevent reaching of limiting installation length, we advice to use "coefficient of safety" according to dimension of the medium-conducting pipe in the range from 1.25 up to 1.5. It is necessary to keep in view that eventual exceeding of σdov can occur as a result of change of operating parameters (rise of temperature) in comparison of original prerequisite.

For conversion the following formula is used:

Li = 
A . σdov

1,25 . Ft
        [m] 

Friction force [ N/m ]

DPE [mm] Burial depth [m]
  0,6 0,7 0,8 0,9 1,0 1,2 1,4 1,6
90 1198 1398 1598 1797 1997 2396 2796 3195
110 1465 1709 1953 2197 2441 2929 3417 3906
125 1664 1942 2219 2497 2774 3329 3884 4438
140 1864 2174 2485 2795 3106 3727 4348 4970
160 2130 2485 2840 3195 3550 4260 4970 5680
180 2396 2796 3195 3595 3995 4793 5592 6390
200 2663 3107 3550 3994 4438 5326 6213 7101
225 2996 3495 3994 4494 4993 5992 6990 7989
250 3328 3883 4438 4992 5547 6656 7766 8875
280 3728 4349 4970 5592 6213 7456 8698 9941
315 4194 4893 5592 6291 6990 8383 9786 11184
355 4726 5514 6302 7090 7877 9453 11028 12604
400 5326 6213 7101 7988 8876 10651 12426 14202
450 5991 6990 7988 8987 9985 11982 13979 15976
500 6657 7766 8876 9986 11095 13314 15533 17752
560 7456 8698 9941 11184 12426 14911 17397 19882
630 8387 10003 11680 13280 14290 16775 19571 22367
710 9453 11273 13164 14967 16104 18905 22056 25207
800 10651 12426 14201 15976 17752 213002 24852 28403

Cross sections of steel pipes

seamless
DN d x s A mm2
20 26,9 x 2,6 198,5
25 33,7 x 2,6 254
32 42,4 x 2,9 359,9
40 48,3 x 2,9 413,6
50 60,3 x 2,9 523
65 76,1 x 3,2 732,8
80 88,9 x 3,6 964,7
100 108,0 x 4,0 1307
100 114,3 x 4,0 1382
125 133,0 x 4,5 1817
125 139,7 x 4,5 1911,3
150 159,0 x 4,5 2184
150 168,3 x 4,5 2311
175 193,7 x 5,6 3309,2
200 219,1 x 6,3 4211,7
250 273,0 x 7,0 5850
ČSN 425710.0 ČSN 426714 ČSN 425715.01

welded
DN d x s A mm2
20 26,9 x 2,3 178
25 33,7 x 2,6 254
32 42,4 x 2,6 325
40 48,3 x 2,6 373,3
50 60,3 x 2,9 523
65 76,1 x 2,9 667
80 88,9 x 3,2 862
100 114,3 x 3,6 1252
125 139,7 x 3,6 1539
150 168,3 x 4,0 2065
175 193,7 x 4,5 2675
200 219,1 x 4,5 3034
250 273,0 x 5,0 4210
300 323,9 x 5,6 5600
350 355,6 x 5,6 6158
400 406,4 x 6,3 7917
450 457,0 x 6,3 8920
500 508,0 x 8,0 9930
DIN 2448 DIN 1629 DIN 2458

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