Cable protection pipes for underground use

Retrofitting cable protection for high-voltage and infrastructure projects without shutdown or interruption

In addition to their classic applications underground, our divisible protective conduit systems offer significant added value for high-voltage and infrastructure projects. Particularly when laying and securing high- and medium-voltage cables in roadworks, railway lines, or utility networks, existing lines can be protected without interrupting power or data transmission.

This solution is suitable for both temporary construction site safety measures and permanent installations on bridges, tunnels, or railway lines where mechanical protection, easy retrofitting, and high supply availability are paramount. Thanks to modular segment lengths and robust material properties, our protective conduits ensure reliable protection against mechanical stress, moisture, and heavy loads in civil engineering applications.

Typical risks for cables and wires

Heavy trucks can damage utility lines running under sidewalks because sidewalks are not designed to withstand high wheel loads . Especially with shallow cover , thin sidewalk construction , and repeated driving or maneuvering, this can lead to subsidence, pipe bursts, or cable damage .

Many utility lines lie at a shallower depth under sidewalks than under streets :

• Telecom / fiber optic: often 30-60 cm

• Power/control cable: 40–80 cm

• Water/sewage (house connections): often only slightly covered

👉 High wheel loads → stress peaks , settlements, pipe bursts, shell damage - crane vehicles, concrete mixers and garbage trucks are particularly critical.

Damage to cables and lines can also be caused by:

• Excavation and civil engineering work (excavation work is the main cause of pipe damage!)
  Most common cause: drilling, scratching or crushing during excavation work.

• Settlements & Ground Movements
  Compaction, subsidence, freeze-thaw cycles, sloping terrain.

• Incorrect or missing bedding
  Point loads caused by stones, rubble or uneven ground.

• Inadequate mechanical protection
  No or insufficiently robust protective tubes, low ring stiffness.

• Temperature and frost damage
  Expansion, embrittlement, frost heave with shallow cover.

• Vibrations & dynamic loads
  Rail transport, trams, trucks, road traffic, machinery, pile drivers.

• Chemical influences
  Oils, fuels, road salt, aggressive soils → material aging.

• Water & Undermining
  Erosion, washing away of the bedding, buoyancy of conduits. (We offer a solution against the buoyancy of conduits, e.g. also for underwater use.)

• Aging & Material Fatigue
  UV damage (at transitions), plasticizer loss, corrosion.

• Improper retrofitting
  Subsequent insertion of cables, excessively tight bending radii, overfilling.

Technical properties of conduits for cable protection

• Material: The protective tubes are made from recycled plastic salvaged from discarded automotive bumpers, possessing precisely the required properties: UV and cold resistance as well as impact resistance. The material is PP-EPDM (polypropylene and ethylene propylene diene monomer rubber). The split cable protection tubes are manufactured using injection molding.

• Inner surface: low friction for optimal blowing technology

• Mechanical strength: high ring stiffness (SN classes), optionally reinforced versions

• UV and weather resistant: for above-ground and underground installation

• Impact and temperature resistant: suitable for demanding environmental conditions

• Compatible with fiberglass blow molding technology

• Compressive and tensile strength: suitable for deep compaction and earth loads

• Lengths: Segment lengths of 100 cm or 120 cm are available.

• Diameter: Available sizes cover outer diameters from 60 mm to 220 mm and inner diameters from 50 mm to 200 mm . Zusätzlich ist bei der Auslegung zu berücksichtigen, dass der Rohrinnendurchmesser auf Basis des Kabelaußendurchmessers zuzüglich mindestens einer Luftreserve von 20 % zu dimensionieren ist, damit es nicht zu einer unzulässigen Erwärmung des Kabels kommt!

• Sealing systems: optionally with sockets, quick-release fasteners or plug-in systems

Typical applications of flexible cable protection for outdoor use

The flexible cable protection pipes for underground and outdoor use are suitable for, among other things, the following applications:

Energy & electricity supply

• Protection of medium and low voltage cables

• Underground cable laying for substations & transformer stations

• Cable protection during network expansion, modernization and redundancy setup

• Protection of sensitive power, control and signaling lines in the energy infrastructure sector, wind turbines and PV systems.

Telecommunications / Fiber optics

• FTTH empty conduits for fiber optic cables ("Fiber to the Home") and infrastructure in the ground

• Protection during subsequent cable installation in established networks

• Repair solutions for damaged underground cables

• Protection systems for backbone connections and redundant fiber optic routes

Rail, Transport, Tunnels & Infrastructure

• Protection of signal cables in the ground

• Bridge and tunnel installations

• Cable ducts along roads, cycle paths and transport structures

• Civil engineering protection systems for traffic control, sensor and IoT infrastructure

• Electric car chargers
  
  
• Airports: Cable protection systems for airports offer reliable protection of power, data and control lines in airport facilities, hangars, taxiways and other safety-critical areas .
  
  Typical areas of application for empty conduits at the airport are:

  • Underground installation of power and control lines for runway lighting, taxiway navigation, and hangar power supply

  • Protection of sensitive data and control cables for control and communication systems in towers, control centers, radar and sensor installations

  • Cable protection for supply systems for lighting, signaling systems, electric vehicle charging stations, signage, security fences, access controls

  • Construction site or temporary cable laying during the expansion, maintenance or extension of airport facilities

  • Retrofit / upgrade of fiber optic or control lines — easy installation without interrupting ongoing flight operations

  • Protection of critical infrastructure components (emergency power, data lines, security systems) under high stress, soil compaction, and road traffic.

Submarine cable

• Protection of submarine cables during land and seabed installation

• Offshore wind farms (export cables & inter-array cables)

• Underwater data cables and fiber optic routes

• Connections between islands and the mainland

• Energy and signal links to offshore platforms

• Protection in coastal and port infrastructure

• Mechanical protection in areas with shipping traffic or anchorage zones

• Stabilization and abrasion protection on rocky or shifting seabeds

Industrial & Plant Engineering

• Factory sites, chemical plants, industrial parks

• Container terminals, logistics centers, port facilities

• Areas with high point or surface loads and dynamic stress

• Protection of sensitive data and control lines in production processes

Construction & Civil Engineering

• Construction site cables and temporary power/data lines

• Permanent cable protection systems in the ground

• Protects against damage from excavators
  
  
• In pipeline construction, especially for retrofitting

• Rapid repair of damage to existing piping systems

• Protective pipes for preparing future cable laying ("empty pipes")

Over 85% of damage in civil engineering projects involves damage to utility lines , often caused by excavators. Almost 60% of this damage involves communication lines, such as fiber optic cables. Other affected lines include gas, water, electricity, sewage lines, and cables.

Consequences: High costs due to repairs, business interruptions, and potential risks to people.

Defense & Security

• Underground protection of communication, alarm and control lines on military sites

• Cable protection systems for mobile or temporary camps, radar or sensor systems

• Secure deployment of drone defense, surveillance and security technology

• Robust cable routes for shooting ranges, depots, training facilities

• Protection of critical infrastructure against sabotage, damage or environmental impact

Critical infrastructure (KRITIS)

• Safe installation of energy, data and monitoring lines for waterworks, sewage treatment plants, pumping stations

• Protection systems in the area of traffic and tunnel control

• Telecommunications and data connections for public safety networks, government and emergency communications

• Protective channels for redundant sections to increase reliability

• Emergency and backup routes for power and data networks

• Protection in areas subject to high security or operational requirements (e.g. airports, power plants, control centers)

The robust protective tubes can also be used to protect water and wastewater pipes as well as (firefighting) hoses, provided their diameter does not exceed 200 mm:

Water and wastewater pipes and hoses

• Protection of water and wastewater pipes and hoses in or above ground

• Mechanical protection of fire extinguishing water, supply, control and measuring lines

• Suitable as protection for retrofitting, repairing and refurbishing existing pipe networks

• Applicable in municipal infrastructure , public utilities, construction sites and industrial water systems, as well as by fire departments, THW (Federal Agency for Technical Relief) and the German Armed Forces.

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Frequently Asked Questions (FAQ) about split cable and conduit protection pipes

1. Basics & Purpose

What is a divisible cable or line protection system?
A mechanical protection system consisting of several segments that can be retrofitted around already installed cables or lines.

Why are divisible systems used?
They enable the protection, repair and reinforcement of existing lines without exposing, disconnecting or taking them out of service.

What problems do such systems solve?
Protection against mechanical damage, pressure loads, earth movements, vibrations, machine traffic, weather and unintentional interference.

2. Materials & Substances

What materials are the systems made of?
Typically made from recycled, high-strength polyolefin-based plastics with elastic components to increase impact resistance.

Why is plastic used?
Plastic is corrosion-free, lightweight, durable, electrically insulating, and resistant to moisture and chemicals.

Are the materials cold-resistant?
Yes, they remain dimensionally stable and impact-resistant even at low temperatures.

Are the materials UV-resistant?
Yes, they are designed for permanent UV exposure and retain their mechanical properties for many years.

Do the materials contain substances that are harmful to health or the environment?
High-quality systems are PAH-free and meet common environmental and safety requirements.

3. Mechanical load capacity & classes

How is the load-bearing capacity specified?
About pressure, load or stiffness classes, which reflect different standard systems.

What is the difference between load classes and stiffness classes?
Load classes describe the maximum pressure absorption, stiffness classes the resistance to deformation under continuous load.

Are the systems suitable for traffic areas?
Yes, depending on the design and installation, they are suitable for areas with vehicular traffic.

Are deep soil coverings possible?
Yes, provided it is correctly sized and professionally installed. Please discuss your specific requirements with us personally.

4. Lifespan & Quality

What is the expected lifespan?
At least 50 years with proper installation and use.

Does the material change over time?
No, high-quality plastics age very slowly and retain their structural integrity.

Are the systems maintenance-free?
Yes, no maintenance is required during normal operation.

5. Assembly & Installation

Can the systems be installed retroactively?
Yes, that is the main use case for such solutions.

Is assembly possible without special tools?
Generally yes, depending on the locking system.

What locking systems are there?
Mechanical click, snap or screw systems, some with multiple stages.

Why are multi-stage locking mechanisms useful?
They secure the segments during transport and assembly and ensure a permanent, durable connection in the final state.

Is underwater installation possible?
Yes, for example by divers, depending on the mounting and environment.

Can it be mounted on rock, concrete, or structures?
Yes, using suitable dowel, screw or mounting systems.

6. Reusability & Flexibility

Can the systems be dismantled?
Yes, many systems are solvable and can be removed.

Is reuse possible?
Yes, for example, in the case of temporary installations or conversions.

Are the systems suitable for repair purposes?
Yes, especially for damaged or exposed cable sections.

7. Logistics, Storage & Handling

In what lengths are the systems supplied?
Usually in handy segments of about 1 m in length.

How is the transport carried out?
Compactly packed on pallets, ready for assembly.

Is external storage possible?
Yes, UV resistance allows outdoor storage; however, protected storage is recommended.

Is worldwide sales or export possible?
Yes.

8. Environment & Sustainability

Are recycled materials used?
Yes, a high proportion of recycled plastic is common.

What environmental benefits result?
Reduced raw material consumption, lower CO₂ emissions, long service life and reusability.

Are these systems part of a circular economy?
Yes, they are often recyclable and support sustainable building concepts.

9. Areas of application

Typical areas of application:

• Energy and electricity supply

• Telecommunications and fiber optics

• Water and wastewater technology

• Rail and transport infrastructure

• Industrial and factory premises

• Civil engineering and pipeline construction

• Repair and refurbishment of existing networks

• Critical infrastructure and security areas

• Temporary installations on construction sites

10. Standards & Planning

Are standards relevant?
Yes, national and international standards are decisive for load-bearing capacity, material properties, and installation. We will gladly provide you with more detailed information upon request.

Do planners need to consider classes and load cases?
Yes, the right choice is crucial for lifespan and safety. We would be happy to advise you personally on selecting the appropriate product for your specific application.

11. Colors, Labeling & Safety

Why are there different colors for protective systems?
Colors serve to visually identify different types of lines (e.g., electricity, data, water) and increase safety during construction, maintenance, and repair work.

Are individual color codes possible?
Yes, depending on the system, components can be manufactured in different colors or supplemented with colored locking or marking elements.

Does color schemes increase workplace safety?
Yes, clear visual identification reduces mistakes, mix-ups and the risk of unintentional damage.

12. Temperature, heat & fire behavior

How temperature-resistant are divisible protective systems?
They are designed for the usual temperature range in the ground and outdoors and retain their function even under strong temperature fluctuations.

Does heat cause deformation?
When used correctly, no relevant deformations occur; prolonged overheating above the intended operating range should be avoided.

How do the materials behave in the event of a fire?
Plastic systems melt rather than splinter, reducing the risk of sharp-edged fractures. Their exact fire behavior depends on the material composition and fire rating. In any case, they are NOT flame-retardant.

13. Chemical & Environmental Resistance

Are the systems resistant to chemicals?
Yes, they are generally insensitive to many substances found in the soil, such as salts, oils, and moisture.

Are the systems suitable for industrial environments?
Yes, especially for factory premises, chemical and industrial plants with increased mechanical and environmental stress.

14. Planning, Design & Installation Practice

What needs to be considered during the planning phase?
Pipe diameter, mechanical loads, soil cover, traffic load, installation environment and future accessibility.

Are special installation instructions required?
Yes, proper bedding, sufficient compaction and correct dimensioning are crucial for performance.

Can the systems be combined with existing lines?
Yes, they are specifically designed for existing networks and retrofits.

15. Economic efficiency & project benefits

Are divisible protection systems economically viable?
Yes, especially for renovations and repairs, as downtime, civil engineering costs and losses are reduced.

What cost advantages result?

• No line interruption

• Faster assembly

• Reduced staffing levels

• Reduced follow-up costs due to longer lifespan

16. Quality Assurance & Testing

Are the systems being tested?
Yes, high-quality protective systems are tested mechanically, thermally, and in terms of materials.

Why are exams important?
They ensure that the specified load and service life values are also achieved under real-world conditions.

17. Typical use cases from practice

When are divisible protective systems used most frequently?

• In case of damaged or exposed cables

• At intersections with roads, paths or railway tracks

• When subsequently reinforcing existing lines

• In safety-critical or difficult-to-access areas

18. Submarine cables & underwater conduits

What is meant by submarine cable?
Submarine cables are power, data or control lines that are laid in coastal areas, rivers, lakes or on the seabed, e.g. for energy transmission, telecommunications or offshore infrastructure.

Why is additional mechanical protection necessary underwater?
Underwater pipelines are exposed to particular risks:

• Anchor throw and trawl nets

• Currents, sediment movement and erosion

• Rockfall, rock contact and abrasion

• Construction and maintenance work in the port and coastal area

What function do protective systems fulfill in underwater applications?
They increase mechanical resistance, reduce abrasion and protect the cable sheathing from point loads.

Is it possible to install the system underwater afterwards?
Yes, divisible protection systems can be retrofitted by divers without having to retrieve the cable.

Are the systems suitable for fresh and salt water?
Yes, corrosion-free plastics are suitable for both freshwater and saltwater environments.

How do currents and waves affect things?
The systems are designed to withstand flow-related forces; proper fixing to the substrate is crucial.

Typical underwater applications:

• Coastal power and data cables

• Port and offshore connections

• Crossings of rivers and lakes

• Underwater pipelines in industrial and factory areas

19. Rail, track & railway infrastructure

Why is cable protection particularly critical in railway areas?
Railway infrastructure is constantly exposed to high mechanical and dynamic loads, including those caused by:

• Axle loads and vibrations

• Settlements in the gravel bed

• Temperature fluctuations

• Maintenance and filling work

Which lines are protected in the vicinity of the railway?

• Signal and control cables

• Energy and electricity supply lines

• Communication and data cables

• Sensor and monitoring cables

Where are safety systems used in the railway sector?

• Under-track crossings

• Cable routes along railway lines

• Transitions to bridges, tunnels and platforms

• Switch and signal areas

Why are divisible systems advantageous in the railway sector?
They allow retrofitting and repairs without track closures or extensive earthworks.

Are the systems resistant to vibration and fatigue?
Yes, elastic plastics reduce stresses caused by vibrations and recurring load changes.

Are the systems suitable for security-relevant applications?
Yes, especially to protect critical signal and control lines, the failure of which would have significant consequences for railway operations.

20. Security, protection & critical infrastructure relevance

Why are cables and lines considered critical infrastructure?
They are essential for energy supply, communication, traffic safety and economic stability.

What additional risks exist?

• Unintentional damage

• Vandalism or sabotage

• Difficult access in case of malfunctions

How do protective systems contribute to resilience?
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