ProtectorFlex® BK pipes
With a FV-O inner layer, heat-resistant, GOST R 70751, up to 500 kV
For underground arranging by any known methods, as well as for the installation of duct banks
01 Description
ProtectorFlex® BK are three-layer heat-resistant pipes made of polymer compound with a special inner layer of FV-0 category.
Sliding additives are added to the composition of the inner layer to reduce friction during cable pulling. Outer layer – a marker layer for cable line labeling.
ProtectorFlex® BK pipes are also intended for the installation of duct banks.
Example of using ProtectorFlex® BK pipes for the installation of duct banks
Versions
Triple-layer version
Inner layer: flame-resistant
Main layer: load-bearing
Outer layer: marker
Dual-layer version
Inner layer: flame-resistant
Outer layer: load-bearing, marker
ProtectorFlex® BK pipes modifications
ProtectorFlex® BK-OMP pipes are three-layer heat-resistant fault-locating pipes made of polymer compound with a special inner layer of FV-0 category.
(at least 50 years)
Key advantages
- Flame-resistant inner layer (FV-0 category)
- Resistant to short-circuiting in the cable
- Heat-resistant throughout the entire service life
- Comply with the requirements of GOST R 70751-2023
- Mechanical strength throughout the entire service life
- Butt-welded
- Flexible, bends require no fittings or manholes
02 Application area
Mechanical protection of high-voltage cable lines
Intended for mechanical protection of high-voltage cable lines of nominal voltage classes up to 500 kV during underground arranging by any known methods (horizontal directional drilling, puncturing, trenchless, etc.), as well as for the installation of duct banks.
Laying methods
- Horizontal directional drilling (HDD)
- Pipe jacking
- Open-cut installation
Approved by the Ministry of Construction of the Russian Federation
Included in the State Estimate Standards by the Ministry of Construction of the Russian Federation: Federal cost estimates for materials used in construction.
(Order No. 899/pr dated December 11, 2015).
Included in the Cost Estimate Standards Database
Included in the TSN-2001 Cost Estimate Standards Database, resource codes: 1.12-5-2490 to 1.12-5-2515 (pursuant to Order No. МКЭ-ОД/26-24 dated March 25, 2026).
Included in the Construction Resources Classifier (CRC), resource codes: 22.21.21.129.59.1.24.04-0317-000 to 22.21.21.129.59.1.24.04-0421-000.
Approved by Rosseti PJSC
ProtectorFlex® pipes comply with the technical requirements of Rosseti PJSC and are recommended for use at the facilities owned by Rosseti PJSC and its subsidiaries.
Certified according to GOST R 70751-2023
ProtectorFlex® pipes are certified under the requirements of GOST R 70751-2023.
03 Product range of ProtectorFlex® BK pipes
|
Pipe outer diameter D, mm |
Ring stiffness SN, kN/m2 | ||||||
| 12 | 16 | 24 | 32 | 48 | 64 | 96 | |
| Pipe wall thickness e, mm | |||||||
| 50 | 2,5 | 2,8 | 3,1 | 3,4 | 3,9 | 4,3 | 4,8 |
| 63 | 3,2 | 3,5 | 4,0 | 4,3 | 4,9 | 5,4 | 6,1 |
| 75 | 3,8 | 4,2 | 4,7 | 5,2 | 5,9 | 6,4 | 7,2 |
| 90 | 4,6 | 5,0 | 5,7 | 6,2 | 7,0 | 7,7 | 8,7 |
|
110 |
5,6 | 6,1 | 6,9 | 7,6 | 8,6 | 9,4 | 10,6 |
| 125 | 6,3 | 6,9 | 7,9 | 8,6 | 9,8 | 10,7 | 12,0 |
| 140 | 7,1 | 7,8 | 8,8 | 9,6 | 10,9 | 11,9 | 13,5 |
| 160 | 8,1 | 8,9 | 10,1 | 11,0 | 12,5 | 13,6 | 15,4 |
| 180 | 9,1 | 10,0 | 11,3 | 12,4 | 14,0 | 15,3 | 17,3 |
| 200 | 10,1 | 11,1 | 12,6 | 13,8 | 15,6 | 17,0 | 19,3 |
| 225 | 11,4 | 12,5 | 14,2 | 15,5 | 17,6 | 19,2 | 21,7 |
| 250 | 12,7 | 13,9 | 15,7 | 17,2 | 19,5 | 21,3 | 24,1 |
| 280 | 14,2 | 15,5 | 17,6 | 19,3 | 21,8 | 23,9 | 27,0 |
| 315 | 15,9 | 17,5 | 19,8 | 21,7 | 24,6 | 26,8 | 30,4 |
| 355 | 18,0 | 19,7 | 22,3 | 24,4 | 27,7 | 30,3 | 34,2 |
| 400 | 20,2 | 22,2 | 25,2 | 27,5 | 31,2 | 34,1 | 38,5 |
| 450 | 22,8 | 24,9 | 28,3 | 31,0 | 35,1 | 38,3 | 43,4 |
| 500 | 25,3 | 27,7 | 31,5 | 34,4 | 39,0 | 42,6 | 48,2 |
| 560 | 28,3 | 31,0 | 35,3 | 38,6 | 43,7 | 47,7 | 54,0 |
| 630 | 31,9 | 34,9 | 39,7 | 43,4 | 49,2 | 53,7 | 60,7 |
04 Technical specifications of ProtectorFlex® BK pipes
| Indicator | Value |
| Climatic version and installation category | UHL1 (climatic category: cold/ temperature), M1 (standard vibration and shock resistant) |
| Mean coefficient of linear thermal expansion at 20–70°С, K-1 | 1,8 х 10-4 |
| Vicat softening point,°С |
Minimum 125 |
| Thermal conductivity, W/(m·K) | Minimum 0,5 |
| Tensile yield strength, MPa | Minimum 21 |
| Tensile breaking stress, MPa | Minimum 37 |
| Tensile elastic modulus, MPa | Minimum 850 |
|
Thermal stability at 200°С, min |
Minimum 180 |
| Elongation at break, % | Minimum 350 |
| Insulation resistance*, MOhm | Maximum 0,1 |
| Shore D surface hardness of the pipe | Minimum 58 |
| Resistance to oils, gasoline, groundwater |
Resistant |
| Flame-resistant inner layer | FV-0 |
| Resistance to ignition by a heated wire, °С | 960 |
| Change in pipe length after heating, % | Maximum 3 |
| Minimum bending radius at 20°С | Minimum 20D* |
* D — is the outer diameter of the pipe.
05 Minimum pipe bending radius
Calculation
Е — modulus of elasticity of the pipe material under tension, MPa
σ — yield strength of the pipe material under tension, MPa
D — pipe outer diameter, mm
For example, at Е = 850 MPa and σ = 21 MPa the minimum bending radius will be r = 20D.
Installation experience proves that the minimum bending radius of the pipe also depends on the ambient temperature at the time of pipe laying.
The final recommendations are presented in the table.
| Minimum allowable bending radius of the pipe depending on the ambient temperature | |||
| Ambient temperature | 0°С | 10°С | 20°С |
| Minimum allowable bending radius | 50D | 35D | 20D |
06
Standart
documentation
- TU 2248-003-34311042-2015
- GOST R 70751-2023
- GOST 35043-2023
07
Example wording for categories
or technical specifications:
- PROTECTORFLEX BK (III) pipe – 160/11,0 SN32 F110 T105 GOST R 70751 / TU 2248-003-34311042-2015
Smooth polymer heat-resistant pipe with a flame-resistant inner layer (FV-0 category), for laying and protecting cable lines up to 500 kV
08
Main
characteristics
Operating temperature
- Long-term allowable heating temperature of cable cores to 105°C
- Minimum permissible operating temperature is -70°C
- In overload mode of cable lines up to 120°C (for 8 hours a day)
- In short-circuit mode up to 250°C on the cable core and 350°C on the cable screen
Shipping length
Standard shipping length is a straight section 13 m (12 m) long or coils of agreed length for pipe diameters up to 110 mm.
09 Documentation
10 Accessories
ProtectorFlex® ZUP protective cable caps
Polymer, watertight
For sealing the ends of backup and operational protective cable pipes
ProtectorFlex® UVK cable seals
Polymer, watertight, heat-resistant, one-phase
For sealing the space between the cable and the pipe
ProtectorFlex® UVK-3 cable seals
Polymer, watertight, heat-resistant, three-phase
For sealing the space between 3 cables and the pipe
ProtectorFlex® TAP transition adapters
Polymer, heat-resistant
For watertight connection of different types of pipes to each other
