Why South Africa’s Mines Trust the SANS Type 41 Cable: A Deep Dive into the Flexible Trailing Cables

Why a Single Cable Type Matters in South Africa’s Mining Industry

If you speak to any mine engineer in the South African gold, coal, or platinum sector, one message comes through loud and clear: a mine is only as reliable as the cables that power it.

In deep-level mines stretching more than 3 km underground, or open-cast pits exposed to abrasive dust, water, fracture zones, and constant vibration, electrical stability is not just a convenience—it is a safety-critical requirement. Every pump, drill rig, loader, bolter, or fan depends on cables that can bend, flex, crawl, reel, push, and pull through some of the world’s harshest working environments.

This is where the SANS Type 41 flexible trailing cable shines. Designed specifically for South African conditions, this cable has earned a reputation as the workhorse of hazardous-area portable equipment. It complies with SANS 1520-1, the national standard governing flexible cables for mines, and is engineered to meet both safety and durability expectations.

This article demystifies the SANS Type 41 cable—from its internal structure to its technical parameters, applications, maintenance practices, standards, and real-world performance in South African mines. Whether you're a mining engineer, apprentice electrician, procurement officer, or cable enthusiast, this is your complete deep-technical yet accessible guide.

The Structure of the SANS Type 41 Cable: What’s Inside the Workhorse

A cable is only as tough as the architecture behind it. The SANS Type 41 cable is built layer-by-layer for mechanical punishment, electrical reliability, screening integrity, and maximum flexibility.

Power Core System

The cable contains:

• Three screened power cores

  Each uses tinned copper conductors for corrosion resistance.

  Wrapped with nylon/tinned copper braid screening to reduce electromagnetic interference.

• One unscreened pilot core
  Used for monitoring, protection circuits, or interlocking.

The four cores are:

• Laid up in right-hand lay

• Surrounding a rubber RD1 filler centre
  → This prevents voids, improves roundness, and stabilises mechanical behaviour.

Conductor

• Class 5 flexible stranded tinned annealed copper

• Highly flexible, low resistance, and ideal for trailing movement and repetitive bending.

Insulation Layer

• EPR (Ethylene Propylene Rubber)

  A thermosetting insulation

  Excellent thermal stability

  Maintains dielectric strength up to 90°C

  Resists partial discharge and moisture

Braid and Reinforcement System

Two different braids serve two different purposes:

• Nylon/tinned copper screen braid over each power core → EMI protection and enhanced mechanical shielding.

• Open nylon reinforcement braid

  Minimum 16 strings

  Provides tensile strength for dragging, reeling, and impact resistance.

Inner and Outer Sheaths

Both sheaths use CR (Polychloroprene Rubber)—renowned for:

• Abrasion resistance

• Fire retardance

• Oil/petroleum resilience

• Flexibility in cold environments

• Water resistance

This makes CR ideal for harsh underground and surface mines where mud, oil, vibration, and impact are unavoidable.

Why This Structure Works in Mining

The layered architecture provides:

• Flexibility for reeling and non-reeling applications

• Durability under high mechanical stress

• Screening to avoid signal interference in sensitive equipment

• Roundness and balance, reducing cable twisting failures

• Thermal and chemical resilience needed in underground atmospheres

In short, Type 41 is designed not just to survive, but to reliably perform in South Africa’s high-risk mining environment.

Materials Used: The Science Behind Durability and Longevity

Every material used in SANS Type 41 is chosen for a specific engineering purpose. Let’s break it down.

Conductor Material: Tinned Copper

• Tinning prevents corrosion in damp environments

• Enhances soldering and connection quality

• Class 5 stranding provides:

  High flexibility

  Greater fatigue life under repeated bending

Insulation: Thermosetting EPR

EPR is superior to PVC or XLPE in:

• High-temperature behaviour

• Flexural endurance

• Water and oil resistance

• Dielectric stability under mechanical stress

Temperature rating: –25°C to +90°C.

Sheathing: Polychloroprene Rubber (CR)

CR sheaths give the cable:

• Flame retardancy (critical in methane zones)

• Excellent abrasion resistance (when dragged across rock surfaces)

• Resistance to hydrocarbons, lubricants, oil, and chemicals

• Very good flexibility even in cold shafts

Screening and Braid Materials

• Nylon braid protects against tensile load

• Tinned copper braid protects against EMI and radio-frequency interference

Together, these materials ensure the cable remains reliable even in:

• Wet, corrosive tunnels

• Hot stopes

• Mobile machinery vibration zones

• Drilling and blasting sectors exposed to shock

Material Standards

The materials comply with:

• SANS 1411-1 (Flame-retardant performance)

• SANS 1411-3 (Halogen content and toxicity requirements)

These standards guarantee performance in hazardous areas where fire, smoke, and corrosion risks must be mitigated.

Technical Specifications

Below is a summary of key technical specifications that matter in engineering and operations.

Voltage Rating

• Uo/U: 640/1100 V
  Suitable for mid-power portable machinery.

Temperature Rating

• Operational: –25°C to +90°C

• Ideal for deep Mine refrigeration zones and hot working environment

Conductor Sizes

• From 2.5 mm² to 25 mm²

Physical Properties

Minimum Bending Radius

• 6 × overall diameter
  Designed for reeling mechanisms and tight underground bends.

Current Ratings at 30°C

Electrical Characteristics

• DC resistance at 20°C: 0.859–5.50 Ω/km

• Reactance: 0.100–0.123 Ω/km

• Symmetrical short-circuit current: 0.49–3.1 kA

• Earth-fault current via screens: 0.5–1.6 kA

These values ensure:

• Low voltage drop

• Stable power distribution

• Strong fault-current performance

• Reliable protection coordination

Compliance Standards

• SANS 1520-1 (Mining flexible cables)

• SANS 1411-1/3 (Fire safety and toxicity)

• Meets requirements for hazardous locations with gas/dust explosion risks

Electrical Performance in Real Mining Conditions

In mining operations, electrical stability determines whether equipment runs safely and efficiently.

Current Carrying Capacity

Type 41’s Class 5 copper conductors allow:

• Smooth current flow

• Low heat generation

• Superior flexibility

Layering on drums reduces cooling, so derating is essential—ignored too often in field operations. Proper derating can prevent:

• Conductor overheating

• Insulation hardening

• Premature failures

Impedance and Voltage Drop

Low impedance ensures:

• Longer operational distances

• Improved voltage regulation for motors

• Reduced flicker under fluctuating load

This is crucial for pumps and fans positioned far from supply points.

Fault Performance

Short-circuit withstand capability protects:

• Transformers

• Switchgear

• MCC panels

This is especially vital in coal mines where arc faults can become ignition sources.

Applications in South African Mining

Typical Applications

• Jumbo drills

• Shuttle cars

• Load-haul-dump (LHD) machines

• Submersible and dewatering pumps

• Ventilation fans

• Portable lighting

• Small conveyors and mobile substations

Underground Environments

Perfect for:

• Damp stopes

• Long-haul tunnels

• Dusty rock faces

• Methane-prone coal sectors

• Platinum mines with heavy mechanical vibration

Open-Pit and Surface Applications

Used extensively for:

• Mobile pumps

• Portable substations

• Wash-down machinery

• Blast-hole drilling rigs

Comparison with Other SANS Cable Types

Type 41 fills the niche for:

• Mobile

• Low-voltage

• Hazard-zone machinery

South African Case: How Type 41 Performs in the Real World

Gold Mine in Carletonville

A large deep-level gold mine used Type 41 cables to power pump stations located 2.7 km underground.
Challenges:

• High humidity (up to 98%)

• Continuous vibration

• Rockfalls damaging trailing cables

Outcome:
Type 41 outperformed the previous PVC-sheathed cable, achieving:

• 19 months longer service life

• 30% fewer unplanned cable repairs

• Improved insulation resistance stability

Open-Cast Coal Mine in Witbank

A reeling application powering mobile dewatering pumps.
Challenge:
Abrasion from sharp coal fragments tore through their previous cable type.

Outcome:
The CR outer sheath and reinforcement braid of Type 41 lasted 2.4× longer, cutting annual cable replacement costs by 42%.

Platinum Mine near Rustenburg

Used Type 41 for LHD trailing applications.
Challenge:
High vibration and tight turning radii caused conductor fatigue in alternative cables.

Outcome:
With Type 41’s nylon reinforcement, conductor breakage reduced by 60%, preventing repeated downtime of a R3M LHD machine.

Frequently Asked Questions (FAQ)

Why is SANS Type 41 suitable for hazardous areas?

Because it offers:

• CR flame-retardant sheaths

• Screened power cores reducing interference

• EPR insulation resistant to heat and moisture

• Compliance with SANS 1520-1, SANS 1411-1/3

How do I select the correct conductor size?

Consider:

• Load current

• Voltage drop distance

• Number of drum layers

• Mechanical tension

• Type of equipment (pump, drill, LHD, etc.)

Can Type 41 be used in wet or flooded areas?

Yes.
CR sheaths offer excellent water resistance, ideal for:

• Pump bays

• Underground dams

• Congolese-style mist zones

What maintenance is recommended?

• Inspect for cuts, swelling, or abrasion

• Ensure correct bending radius (6 × OD)

• Avoid sharp edges on cable guides

• Test insulation resistance periodically

• Check terminations for corrosion

How does it differ from Type 61 or Type 63?

• Type 41 is specifically for portable, flexible, low-voltage equipment

• Type 61/63 cover higher voltages or heavier mechanical loads

Why the SANS Type 41 Cable Continues to Lead in South African Mining

The SANS Type 41 cable is not just another flexible trailing cable—it is a reliable, field-proven, safety-oriented engineering product built specifically for South Africa’s mining ecosystem. Its combination of:

• High mechanical durability

• Low-voltage flexibility

• Reinforced braiding

• High-quality EPR and CR materials

• SANS 1520-1 compliance

• Excellent electrical performance

makes it one of the most trusted and widely used cable types in the country.

Whether powering pumps, drills, LHDs, fans, or portable substations, the Type 41 cable supports the backbone of South Africa’s mining productivity—and helps ensure safe, stable operations in some of the world’s most challenging underground environments.

Contact Anhui Feichun Special Cable Co., Ltd.

For comprehensive technical specifications and quotations, please contact our specialized mining cable engineering team:

Technical Engineering Support:

tech@feichuncables.com

Sales Engineering Department:

Li.wang@feichuncables.com

WhatsApp Contact:

Manufacturer: Anhui Feichun Special Cable Co., Ltd. (安徽飞纯特种电缆有限公司)

Manufacturing Headquarters: Building A, Private Science and Technology Park, Hefei Economic and Technological Development Zone, Anhui Province, People’s Republic of China

+86 17333223430