Understanding the Design Philosophy: Why FABER Reelingflex Exists Between Two Worlds

When you examine the spectrum of industrial reeling cables available in the market today, you encounter a clear categorization. On one side, there are cables designed for permanent outdoor installation—like the TROMMELFLEX NSHTÖU-J with its heavy neoprene sheath and decade-long lifespan. On the other side, there are cables designed for protected indoor environments where fire safety is paramount, such as the TROMMELFLEX PUR-HF. But there exists a third category of application that neither pure outdoor nor pure indoor cables are optimally suited for, and this is where the FABER Reelingflex finds its purpose.

Consider the workflow of a large quarrying operation. A quarry operates equipment—mobile bucket-wheel excavators, conveyor systems, water pumps, drills—that must be powered. Unlike a permanently installed seaport crane that sits in one location for decades, or an indoor warehouse that remains temperature-controlled and sheltered, a quarry’s equipment is semi-mobile. It might operate in one section of the quarry for six months, then be relocated to another section. The cable powering this equipment must be robust enough to survive outdoor exposure and mechanical abuse, but it is not expected to remain in service for fifteen years. It might need only five to seven years of operational life before equipment replacement or relocation makes it obsolete. Additionally, because quarry operations involve dust, explosive atmospheres in some cases, and safety regulations increasingly demanding halogen-free materials, the cable must be constructed from materials that do not release toxic gas in a fire, even though the cable will not experience the extreme UV and moisture exposure that neoprene is specifically formulated to withstand.

This is the gap that FABER Reelingflex fills. It is a halogen-free cable with polyurethane sheathing for environmental safety. But rather than using the soft, flexible polyether-based PUR of the TROMMELFLEX PUR-HF, which is optimized for extreme cold flexibility, Reelingflex employs a different insulation technology—XLPE (cross-linked polyethylene)—that offers superior rigidity, better resistance to thermal cycling, and enhanced mechanical strength. Additionally, it incorporates a Kevlar self-supporting element, which fundamentally changes how the cable can be deployed. Let me explain why these design choices matter.

XLPE vs. EPR Insulation: The Molecular Difference That Matters for Mining Applications

To truly appreciate the FABER Reelingflex design, we must first understand the difference between its XLPE insulation and the EPR insulation used in cables like the RHEYFIRM and many variants of TROMMELFLEX. On the surface, both are polymer-based insulations suitable for 0.6/1 kV applications. But their molecular structures are fundamentally different, and this difference becomes critical when you understand the mining environment.

The Molecular Architecture of XLPE

XLPE stands for cross-linked polyethylene. To understand this, we must start with polyethylene (PE), which is one of the simplest and most commonly used polymers. Polyethylene is simply long chains of carbon atoms with hydrogen atoms attached. In its untreated form, polyethylene chains are independent—they can slide past each other freely, which makes the material soft and stretchy. However, when polyethylene is “cross-linked”—a process in which chemical bridges are created between the polymer chains, typically using peroxides or radiation—the material becomes much more rigid. These cross-links act like molecular welds, preventing the chains from moving independently.

The result of cross-linking is a material with significantly higher tensile strength, greater resistance to thermal deformation, and superior resistance to environmental stress. An XLPE insulation will not soften at elevated temperatures the way an untreated polymer might. It will not creep (gradually deform under constant stress) the way EPR sometimes does after years of exposure. This makes XLPE particularly suitable for cables that experience thermal cycling, continuous mechanical stress, and exposure to temperature variations in outdoor or semi-outdoor environments.

The Molecular Architecture of EPR

EPR—ethylene propylene rubber—is fundamentally different. Rather than being a synthetic polymer like XLPE, EPR is classified as an elastomer, which means its molecular chains are designed to flex and return to their original shape without permanent deformation. This is achieved through a different chemical structure where ethylene and propylene monomers are combined in a specific ratio, allowing the polymer chains to uncoil and recoil elastically.

EPR’s strength is in its flexibility and low-temperature performance. A cable insulated with EPR remains soft and pliable even at −40°C or lower, which is why EPR is ideal for the PUR-HF cables used in cold storage facilities. However, EPR’s weakness becomes apparent in thermal cycling stress. When an EPR cable experiences repeated heating and cooling, the polymer chains undergo expansion and contraction at each temperature change. Over time, this cycling can cause what is called “stress relaxation,” where the material gradually loses its mechanical properties.

Why XLPE Matters in Mining Quarries

In a typical quarry, ambient temperatures can swing from −5°C in winter mornings to +45°C in summer afternoons. This is not the extreme cold of arctic mining (where EPR excels) nor is it the controlled environment of an indoor warehouse. It is a moderate range of thermal cycling that occurs hundreds of times per year. For a cable with a five to seven year operational life in a quarry, this thermal cycling, combined with the mechanical stress of being spooled, unspooled, and occasionally dragged across rough terrain, creates an environment where XLPE’s superior rigidity and thermal stability become advantageous.

Furthermore, quarries produce significant dust and particulate matter. This dust can migrate into the cable structure, especially if there are micro-cracks or delamination issues. XLPE’s superior cross-linked structure creates a more tortuous path for moisture and dust ingress compared to EPR. This means a Reelingflex cable exposed to dusty quarry conditions will experience slower degradation of its insulation properties compared to an EPR-based alternative.

It is important to note that XLPE is not inherently “better” than EPR—it is simply optimized for a different set of conditions. In cold storage at −40°C, XLPE would become too rigid and could crack under bending stress. In a quarry at moderate temperatures with moderate thermal cycling, XLPE maintains its properties more consistently over the cable’s expected service life.

Kevlar Self-Supporting Element: Engineering the Cable That Carries Itself

Perhaps the most distinctive feature of the FABER Reelingflex, and the feature that most clearly defines its intended applications, is the integrated Kevlar self-supporting element. To understand why this is so important, we must first appreciate the practical challenges of deploying cables in temporary or semi-permanent installations.

The Problem Reelingflex Solves: Cable Support in Temporary Deployments

Imagine a construction site where a temporary concrete pump needs to be powered. The pump is positioned 200 meters from the nearest power source. In a traditional approach, you would run a standard power cable from the source to the pump, but you would also need to support that cable. You might use cable trays, cable hangers, or guide channels every few meters to prevent the cable from sagging excessively under its own weight. This adds cost, complexity, and time to the site setup.

The Kevlar self-supporting element in the Reelingflex fundamentally changes this equation. Kevlar is an aramid fiber with exceptional tensile strength—about 2600 MPa, nearly the strength of steel wire of equivalent weight. By incorporating Kevlar strands directly into the cable structure, FABER has created a cable that can support its own weight over spans of 20 to 30 meters without sagging excessively. This means that for temporary or semi-temporary installations in quarries, construction sites, and remote mining operations, the Reelingflex cable can be strung between support points with minimal additional infrastructure.

How the Self-Supporting Element is Integrated

The Kevlar element in Reelingflex is not simply added as an external wrap, like the anti-torsion braid in some cables. Rather, it is integrated into the core structure of the cable. Specifically, Kevlar fibers are twisted or braided in a helical pattern around the conductor insulation assembly, creating a structural element that is part of the cable’s load-bearing architecture. This integration serves two purposes simultaneously: it provides tensile support to suspend the cable between distant points, and it also contributes to the cable’s torsion resistance during reeling operations.

The specification notes that Reelingflex is “not suitable for monospiral drums,” which is an important caveat. Monospiral drums are single-layer reels where the cable is wound in a single spiral pattern without overlapping. The reason for this limitation is that the Kevlar element, while providing outstanding tensile strength, has less flexibility than rubber-based materials. In a monospiral configuration where cable is wound in a single layer, the differential tension and bending stresses would concentrate on the Kevlar element in a way that could cause fatigue failure. For standard multi-layer drum configurations or festoon systems, the Reelingflex performs excellently, with the Kevlar providing both tensile support and improved mechanical performance.

Technical Specifications and Compliance Framework

The FABER Reelingflex is certified to VDE 0482-332-1-2 and IEC 60332-1-2 standards, which are German and international standards for flame-retardant power cables. Let us examine the key specifications and understand what each one tells us about the cable’s intended performance.

Comparative Analysis: Reelingflex vs. TROMMELFLEX vs. Commodity Alternatives

To help engineers and procurement specialists understand where the FABER Reelingflex fits in the spectrum of available products, let us conduct a detailed comparison across the most common cable types used in quarrying and construction applications.

Understanding the Comparison

The comparison reveals that the FABER Reelingflex occupies a distinct position. It is more expensive than commodity SOOW cables, but this premium reflects genuine engineering advantages: halogen-free safety, self-supporting capability, and XLPE insulation’s superior thermal stability. Compared to the TROMMELFLEX variants, Reelingflex is not the best choice for extreme cold (PUR-HF excels there), nor is it optimized for decades-long outdoor permanence (NSHTÖU-J is superior). Rather, Reelingflex is the optimal choice when you need a cable for semi-temporary installation (five to seven years) in quarrying or construction environments, where halogen-free compliance is mandatory, and where the self-supporting Kevlar element provides significant logistical advantage.

Real-World Applications: Where Portability and Semi-Permanent Installation Collide

Quarrying Operations: Mobile Pump and Water System Power

In a typical limestone or aggregate quarry, water pumps are essential for dust suppression, equipment cooling, and processing. These pumps are often relocated as quarry operations shift from one extraction zone to another. A FABER Reelingflex cable can be strung between support points on the quarry infrastructure (existing utility poles, equipment structures, or temporary poles), powered from a central generator or grid connection. The Kevlar self-supporting element means the cable can span 25–30 meters between supports without requiring intermediate cable trays or hangers. When the quarry operations move to a new zone, the cable can be recovered, the Kevlar element ensures it handles the tension of being pulled back without damage, and the halogen-free composition ensures compliance with increasingly strict quarry safety regulations regarding fire hazards.

Construction Site Temporary Power Distribution

Large construction projects often deploy temporary electrical distribution systems to power concrete pumps, hoists, lighting, and site facilities. A FABER Reelingflex cable can be installed on festoon systems (overhead cable carriers) to feed power to moving equipment like concrete pumps on high-rise building sites. The ability to operate at 200 m/min on festoon systems, combined with the self-supporting element and halogen-free safety profile, makes Reelingflex well-suited for these applications. When the site is completed, the cable is recovered and typically finds use on the next project, which aligns with a five to seven year service life expectancy.

Mining Operations: Temporary Exploration and Secondary Equipment

In open-pit mining, primary operations use permanently installed infrastructure. However, secondary equipment—dewatering pumps, ventilation fans, emergency backup systems—is often deployed on a project or campaign basis. A FABER Reelingflex cable provides the safety and environmental compliance required by modern mining regulations while avoiding the cost premium of a neoprene cable that would be over-engineered for temporary duty cycles.

Cost-Benefit Analysis and Total Cost of Ownership

FABER Reelingflex cables are priced at approximately €16–20 per meter, positioning them above commodity alternatives but below specialized outdoor cables like NSHTÖU-J. The question for procurement specialists is whether the premium is justified by the cable’s features and expected performance.

Consider a typical scenario: a quarry company needs to deploy temporary power distribution across a 300-meter span to supply pumps at a new extraction zone. The project timeline is five years, after which operations will shift elsewhere. The company evaluates three options.

Option A: Commodity SOOW Cable (€10/meter) — Material cost: 300 m × €10 = €3,000 | Installation labor: high (requires cable supports every 4 meters) = €2,500 | Environmental compliance: non-halogen-free (some quarries face regulatory penalties) = potential €5,000 fine | Replacement after three years: €3,000 + €2,500 labor = €5,500 | Total five-year cost: €18,500 | Environmental risk: significant.

Option B: TROMMELFLEX NSHTÖU-J (€13/meter) — Material cost: 300 m × €13 = €3,900 | Installation labor: moderate (fewer supports needed) = €1,200 | Environmental compliance: guaranteed halogen-free = €0 penalty | Ten-year design life (cable exceeds project requirements): no replacement needed = €0 | Total five-year cost: €5,100 | Environmental risk: zero, but you have over-engineered for a five-year project.

Option C: FABER Reelingflex (€18/meter) — Material cost: 300 m × €18 = €5,400 | Installation labor: minimal (self-supporting element, fewer supports needed) = €500 | Environmental compliance: guaranteed halogen-free = €0 penalty | Self-supporting capability advantage: eliminates €2,000 in temporary infrastructure costs = advantage | Replacement at end of five years: cable has reached expected end of life, designed for this cycle = €0 surprise | Total five-year cost: €5,900 (including infrastructure savings) | Environmental risk: zero.

From this analysis, options B and C cost nearly the same over the five-year project timeline. However, option B requires that the quarry company commit to a cable engineered for fifteen years when only five years are needed—wasting the engineering investment. Option C is specifically designed for this duty cycle, making it the most economically rational choice. Additionally, if the quarry company operates multiple sites or projects simultaneously, the ability to redeploy Reelingflex cables across sites (since they are not damaged by relocation, thanks to the Kevlar element) extends their utilization and further improves the economic case.

Technical FAQ and Field Deployment Guidelines

Can FABER Reelingflex be spooled on a monospiral drum?

No, the product literature explicitly states that Reelingflex is not suitable for monospiral drums. The reason is that the Kevlar self-supporting element, while providing outstanding tensile strength and torsion resistance, is less flexible than rubber-based components. In a monospiral (single-layer) configuration, the cable would experience non-uniform bending stress concentrated on the Kevlar, which could lead to fatigue failure over extended use. For standard multi-layer drums (used in nearly all commercial reeling systems) or festoon systems, Reelingflex performs excellently. If your application specifically requires monospiral compatibility, please consult the cable manufacturer for alternative recommendations.

What is the maximum span length for using the Kevlar self-supporting element?

The Kevlar element is designed to support the cable’s own weight over spans of approximately 25–30 meters with acceptable sag (typically less than 0.5 percent of span length). Spans exceeding 30 meters are possible but require engineering analysis to ensure that sag and tension forces remain within acceptable limits for the specific cable size and installation. For spans beyond 40–50 meters, intermediate support points are recommended. FeiChun’s engineering team can provide detailed span calculations based on your specific conductor size and environmental conditions.

Is the XLPE insulation suitable for extended operation at the full 90°C conductor temperature?

Yes, XLPE is rated for continuous operation at 90°C conductor temperature, which is standard for industrial duty cycles. However, sustained operation at or near the temperature limit accelerates aging of the insulation. For maximum cable lifespan, we recommend operating at conductor temperatures below 75°C when feasible. This provides a safety margin and extends the cable’s serviceable life. If your application requires sustained high-temperature operation, please verify that the cable’s actual operating temperature (which depends on ambient temperature, current load, and installation method) will not exceed 80°C on a continuous basis.

How does the halogen-free PUR sheath perform compared to neoprene in terms of long-term durability?

The halogen-free PUR sheath in Reelingflex will degrade more rapidly than neoprene under extreme UV exposure (10+ years in direct sunlight). For typical quarry and construction site applications where cables are not exposed to intense UV for extended periods, or where cables are relocated every few years, PUR provides adequate protection. If your application involves permanent outdoor installation with intensive sun exposure, a neoprene-sheathed cable (like NSHTÖU-J) would be more appropriate. For five to seven year temporary installations typical of quarries and construction, PUR is adequate and offers the important advantage of halogen-free fire safety.

Can Reelingflex be spliced mid-run if a section is damaged?

Yes, the cable can be spliced using properly rated crimp connectors or other mechanical splicing methods. However, the Kevlar self-supporting element introduces complexity to the splice. A proper splice must account for the mechanical strength provided by the Kevlar and ensure that the splice does not become a weak point. For this reason, we recommend that any mid-run splicing be performed by qualified cable technicians with experience with self-supporting cables. Alternatively, the damaged section can be removed entirely and a new continuous cable installed from source to load, which is often simpler and more reliable than attempting a complex splice.