DM1N\/2M2N Flexible Armoured MV Mining Cable \u2014 Longwall Shearer & Drill Jumbo Engineering | Feichun 2026<\/title>\n <style>\n :root {\n --primary-color: #1a3a52;\n --primary-light: #2d5a7b;\n --primary-dark: #0f1f2e;\n --accent-armour-mv: #455a64;\n --accent-port: #0277bd;\n --accent-marine: #00796b;\n --accent-load: #d32f2f;\n --accent-rope: #ff6f00;\n --accent-mine: #5d4037;\n --neutral-light: #f5f8fa;\n --neutral-medium: #cfd8e3;\n --neutral-dark: #546e7a;\n --text-primary: #1a1a1a;\n --text-secondary: #555555;\n --border-color: #e0e6ed;\n }\n\n * {\n margin: 0;\n padding: 0;\n box-sizing: border-box;\n }\n\n @import url('https:\/\/fonts.googleapis.com\/css2?family=Source+Serif+4:wght@400;600;700&family=Instrument+Sans:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500;600&display=swap');\n\n html,\n body {\n font-family: 'Instrument Sans', sans-serif;\n color: var(--text-primary);\n background: #ffffff;\n line-height: 1.6;\n width: 100%;\n overflow-x: hidden;\n }\n\n \/* 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border-left: 4px solid var(--accent-armour-mv);\n }\n .tech-highlight h4 {\n margin-top: 0;\n color: var(--primary-color);\n }\n .tech-highlight p {\n color: var(--text-secondary);\n line-height: 1.8;\n }\n\n \/* \u2500\u2500 SECTION DIVIDER \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n .section-divider {\n display: flex;\n align-items: center;\n gap: 16px;\n margin: 56px 0 6px;\n }\n .section-divider-badge {\n background: var(--accent-armour-mv);\n color: white;\n padding: 6px 14px;\n border-radius: 4px;\n font-size: 11px;\n font-weight: 700;\n text-transform: uppercase;\n letter-spacing: 1px;\n white-space: nowrap;\n }\n .section-divider hr {\n flex: 1;\n border: none;\n border-top: 2px solid var(--border-color);\n }\n\n \/* \u2500\u2500 FOOTER \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n .doc-footer {\n background: var(--primary-dark);\n color: white;\n padding: 40px 0;\n margin-top: 60px;\n }\n .doc-footer h4 {\n color: white;\n font-size: 18px;\n margin-bottom: 14px;\n }\n .doc-footer p {\n margin-bottom: 8px;\n color: rgba(255, 255, 255, 0.88);\n font-size: 14px;\n }\n .doc-footer a {\n color: #4dd0e1;\n text-decoration: none;\n }\n .doc-footer a:hover {\n color: #80deea;\n text-decoration: underline;\n }\n .doc-ip-notice {\n background: rgba(255, 255, 255, 0.08);\n padding: 16px;\n border-radius: 4px;\n margin-top: 20px;\n font-size: 12px;\n line-height: 1.65;\n border-left: 4px solid var(--accent-rope);\n }\n .doc-id {\n text-align: center;\n font-size: 12px;\n color: rgba(255, 255, 255, 0.55);\n margin-top: 24px;\n padding-top: 20px;\n border-top: 1px solid rgba(255, 255, 255, 0.1);\n }\n\n @media (max-width: 640px) {\n .doc-header h1 {\n font-size: 28px;\n }\n .doc-content h2 {\n font-size: 24px;\n }\n .spec-card-value {\n font-size: 22px;\n }\n .container {\n padding: 0 16px;\n }\n .doc-header {\n padding: 32px 0;\n }\n .doc-content {\n padding: 28px 0;\n }\n .doc-footer {\n padding: 32px 0;\n }\n }\n <\/style>\n<\/head>\n<body>\n\n \n <div class=\"doc-header\">\n <div class=\"container\">\n <span class=\"doc-header-badge\">\u2699 DM1N \/ 2M2N Armoured<\/span>\n <span class=\"doc-header-badge standard\">Medium-Voltage Mobile Equipment<\/span>\n <h1>DM1N\/2M2N Flexible Armoured Mining Cable \u2014 Longwall Shearer & Drill Jumbo Engineering<\/h1>\n <p>A comprehensive technical analysis of medium-voltage flexible armoured mining cables for extreme duty applications \u2014 from galvanized steel and copper mixed-braid flexible armour design through semi-conductive layer architecture, independent phase shielding, and mechanical protection engineering for longwall shearers and drill jumbos operating at 1.8\/3 kV to 3.6\/6 kV.<\/p>\n <div class=\"doc-meta\">\n <span>\u26a1 Voltage: 1.8\/3 kV \u2013 3.6\/6 kV<\/span>\n <span>\ud83c\udf21 EPR: 90\u00b0C continuous<\/span>\n <span>\ud83d\udd17 Class 5 tinned copper<\/span>\n <span>\ud83d\udee1 Steel+copper flexible armour<\/span>\n <span>\ud83d\udccb Semi-conductive + shield layers<\/span>\n <\/div>\n <\/div>\n <\/div>\n\n \n <div class=\"container\" style=\"margin-top: 40px;\">\n <div class=\"spec-grid\">\n <div class=\"spec-card\">\n <div class=\"spec-card-label\">Conductor<\/div>\n <div class=\"spec-card-value\">Class 5<\/div>\n <div class=\"spec-card-unit\">Tinned copper, ultra-flexible for reel\/drag duty<\/div>\n <\/div>\n <div class=\"spec-card\">\n <div class=\"spec-card-label\">Insulation<\/div>\n <div class=\"spec-card-value\">EPR<\/div>\n <div class=\"spec-card-unit\">High-purity, 90\u00b0C continuous MV operation<\/div>\n <\/div>\n <div class=\"spec-card\">\n <div class=\"spec-card-label\">Semi-Conductive Layers<\/div>\n <div class=\"spec-card-value\">Yes<\/div>\n <div class=\"spec-card-unit\">Inner + outer for MV field stress control<\/div>\n <\/div>\n <div class=\"spec-card\">\n <div class=\"spec-card-label\">Phase Shielding<\/div>\n <div class=\"spec-card-value\">Independent<\/div>\n <div class=\"spec-card-unit\">Tinned copper braid per phase; EMI control<\/div>\n <\/div>\n <div class=\"spec-card\">\n <div class=\"spec-card-label\">Flexible Armour<\/div>\n <div class=\"spec-card-value\">Steel+Cu<\/div>\n <div class=\"spec-card-unit\">Galvanized steel + copper mixed braid; crush & cut resistant<\/div>\n <\/div>\n <div class=\"spec-card\">\n <div class=\"spec-card-label\">Outer Sheath<\/div>\n <div class=\"spec-card-value\">PCP\/PUR<\/div>\n <div class=\"spec-card-unit\">Heavy-duty, abrasion-resistant mining compound<\/div>\n <\/div>\n <\/div>\n <\/div>\n\n \n <div class=\"container\" style=\"margin-top: 40px;\">\n <div class=\"toc-section\">\n <h3>\ud83d\udccb Article Contents<\/h3>\n <div class=\"toc-divider\">A \u2014 Standard Identity & Complexity Drivers<\/div>\n <ol>\n <li><a href=\"#s1\">What Is DM1N\/2M2N? The Medium-Voltage Flexible Armoured Standard for Extreme Mobile Equipment<\/a><\/li>\n <li><a href=\"#s2\">Why Medium-Voltage Cables Require Fundamentally Different Internal Architecture<\/a><\/li>\n <li><a href=\"#s3\">Flexible Armour Misconception \u2014 Why DM1N Is Not Conventional SWA or STA<\/a><\/li>\n <\/ol>\n <div class=\"toc-divider\" style=\"margin-top:14px;\">B \u2014 Structural Layers & Engineering Rationale<\/div>\n <ol start=\"4\">\n <li><a href=\"#s4\">Conductor Through Inner Sheath: Class 5 Tinned Copper to MV Buffering<\/a><\/li>\n <li><a href=\"#s5\">Semi-Conductive Inner Layer: Why Medium-Voltage Requires Electric Field Smoothing<\/a><\/li>\n <li><a href=\"#s6\">Insulation and Semi-Conductive Outer Layer: Preventing Corona Damage at MV<\/a><\/li>\n <li><a href=\"#s7\">Independent Phase Shielding: Per-Phase EMC Protection in Multi-Core Design<\/a><\/li>\n <li><a href=\"#s8\">Flexible Armour: Galvanized Steel + Copper Mixed Braid for Extreme Mechanical Duty<\/a><\/li>\n <\/ol>\n <div class=\"toc-divider\" style=\"margin-top:14px;\">C \u2014 Performance, Applications & Compliance<\/div>\n <ol start=\"9\">\n <li><a href=\"#s9\">Medium-Voltage Testing: Dielectric Withstand and Partial Discharge Measurement<\/a><\/li>\n <li><a href=\"#s10\">Longwall Shearer and Drill Jumbo Cable Duty: Mechanical Stress Analysis<\/a><\/li>\n <li><a href=\"#s11\">Total Cost of Ownership: When Ultra-Heavy-Duty Armour Justifies Extreme Premium<\/a><\/li>\n <\/ol>\n <\/div>\n <\/div>\n\n \n <div class=\"container\">\n <div class=\"doc-content\">\n\n <div class=\"section-divider\">\n <span class=\"section-divider-badge\">A<\/span>\n <hr>\n <span style=\"font-size:13px; color:var(--text-secondary);\">Standard Identity & Complexity Drivers<\/span>\n <\/div>\n\n <h2 id=\"s1\">1. What Is DM1N\/2M2N? The Medium-Voltage Flexible Armoured Standard<\/h2>\n\n <p>\n DM1N and 2M2N designations represent the apex of mining cable complexity \u2014 flexible armoured cables engineered for medium-voltage (1.8\/3 kV, 3.6\/6 kV) mobile equipment operating in the most mechanically extreme underground environments. These cables are specified for longwall coal shearers, hydraulic drill jumbos, and other continuous-operation mobile equipment that simultaneously demand ultra-high mechanical durability and medium-voltage electrical capability.\n <\/p>\n\n <p>\n The fundamental engineering challenge that defines DM1N\/2M2N is this: medium-voltage cables require internal semi-conductive layers and sophisticated insulation architecture to prevent corona discharge (electrical breakdown at high voltage), but they must simultaneously maintain the extreme mechanical flexibility required for cable reel winding and equipment drag duty. This convergence is far more difficult than it might appear, because the semi-conductive layers and additional insulation walls that prevent corona also inherently reduce mechanical flexibility and increase cable stiffness.\n <\/p>\n\n <div class=\"tech-highlight\">\n <h4>\u2699 The Paradox at the Heart of DM1N\/2M2N Design<\/h4>\n <p>A conventional industrial medium-voltage power cable (such as IEC 60502-4 copper MV cable) might achieve flexibility of 8\u201310\u00d7 O.D. bending radius. But that flexibility is adequate only because the cable is installed in fixed conduit routes and experiences minimal dynamic reeling and dragging. A mining cable must achieve 5\u20136\u00d7 O.D. flexibility while simultaneously operating at medium voltage with multiple semi-conductive and shielding layers. This forces cable engineers into a relentless optimization process: minimizing insulation thickness while maintaining dielectric strength, using compressible sheath materials that yield under bending to prevent insulation cracking, and selecting semi-conductive compounds that are flexible rather than rigid. Every design decision represents a trade-off between electrical safety (requiring thicker insulation and protective layers) and mechanical performance (requiring minimum material thickness for flexibility).<\/p>\n <\/div>\n\n <h2 id=\"s2\">2. Why Medium-Voltage Cables Require Fundamentally Different Internal Architecture<\/h2>\n\n <p>\n A 0.6\/1 kV cable (like UNE 22511 or DS1N) operates with a maximum electric field stress of approximately 5\u20137 kV\/mm within the insulation. Modern EPR compounds can sustain this field indefinitely without degradation. But jump to 3.6\/6 kV \u2014 a 6\u00d7 voltage increase \u2014 and the peak electric field stress increases to 30\u201340 kV\/mm, approaching the limits of material breakdown. At these stress levels, unsmoothed electric field concentrations at conductor surface edges or insulation voids can initiate corona discharge \u2014 tiny electrical streamers that gradually degrade insulation from the inside, eventually leading to catastrophic breakdown.\n <\/p>\n\n <p>\n To prevent this, medium-voltage cables employ semi-conductive inner and outer layers directly adjacent to the insulation. These layers, manufactured from EPR or rubber compounds with controlled electrical conductivity (typically 1\u201310 Siemens\/meter), ensure that the electric field across the insulation is uniform and perpendicular to the conducting surfaces \u2014 the ideal geometry for stress distribution. The semi-conductive layers act as field-smoothing electrodes, eliminating sharp electric field gradients that would initiate corona.\n <\/p>\n\n <h2 id=\"s3\">3. Flexible Armour Misconception \u2014 Why DM1N Is Not Conventional SWA or STA<\/h2>\n\n <p>\n A critical misunderstanding arises when engineers unfamiliar with mining cable technology encounter the term “armoured” in DM1N\/2M2N specifications. They may assume this refers to the steel wire armour (SWA) or steel tape armour (STA) commonly found in fixed-installation industrial power cables. These armours are rigid by design \u2014 they provide excellent crush and puncture protection but impose minimum bending radii of 12\u201320\u00d7 cable diameter, making them physically incompatible with mobile equipment reel operations.\n <\/p>\n\n <p>\n DM1N’s armour is categorically different. It is a flexible mixed-braid armour composed of galvanized steel wire combined with pure copper wire, both woven at a high lay angle (45\u201360\u00b0) to maximize flexibility. The design is predicated on a counter-intuitive principle: the steel wires provide extreme resistance to crushing and cutting, while the copper wires serve an equally critical but different function \u2014 they ensure that if the cable is severed by catastrophic mechanical damage (crushed by a falling boulder, sheared by a shearer blade), the instant the outer sheath breaks and the copper wires are exposed, they will short-circuit against the steel armour structure. This instantaneous short-circuit generates a massive fault current that trips the mine’s protective relay within milliseconds, immediately de-energizing the cable before an electrical arc can initiate and potentially ignite methane or coal dust explosions.\n <\/p>\n\n <div class=\"note mv\">\n <strong>\u26a0\ufe0f The Anti-Explosion Design Philosophy Behind Copper-Steel Armour<\/strong>\n In conventional industrial settings, a severed cable is merely an operational annoyance. In underground coal mines, a severed cable can become a lethal initiator if the electrical arc created by the severance ignites accumulated methane gas or coal dust. Feichun’s flexible armour design eliminates this risk through engineered fault-initiation: the copper-steel composite ensures that mechanical damage instantly creates an electrical fault condition, triggering protective equipment response before arc energy can accumulate. This is not merely a cable design choice \u2014 it is a safety-critical mining equipment requirement.\n <\/div>\n\n <div class=\"section-divider\">\n <span class=\"section-divider-badge\">B<\/span>\n <hr>\n <span style=\"font-size:13px; color:var(--text-secondary);\">Structural Layers & Engineering Rationale<\/span>\n <\/div>\n\n <h2 id=\"s4\">4. Conductor Through Inner Sheath: Class 5 Tinned Copper to MV Buffering<\/h2>\n\n <p>\n The outermost conductor layer in a DM1N cable remains Class 5 tinned copper \u2014 extremely fine strands with individual wire diameter \u22640.25 mm, precisely matching the specification of low-voltage mining cables. The tinning (zinc coating) prevents oxidation in wet mine environments and facilitates field termination by ensuring clean solder joints at connector crimps.\n <\/p>\n\n <p>\n Immediately surrounding the conductor is the inner semi-conductive layer \u2014 a thin shell of EPR or rubber compound formulated with graphite or carbon black to provide controlled electrical conductivity. This layer serves as the inner electrode of the insulation system, ensuring that the electric field within the main insulation begins at a smoothed, uniform potential surface rather than at sharp conductor strand edges that would create field concentration points.\n <\/p>\n\n <h2 id=\"s5\">5. Semi-Conductive Inner Layer: Why Medium-Voltage Requires Field Smoothing<\/h2>\n\n <p>\n The inner semi-conductive layer is applied by extrusion directly onto the conductor bundle. Its thickness is typically 0.3\u20130.5 mm, and its conductivity is specified at 1\u201310 Siemens\/meter \u2014 high enough to ensure equipotential surfaces at the interface with the insulation, but low enough that it doesn’t create significant current leakage pathways during normal operation.\n <\/p>\n\n <p>\n Testing per IEC 60811-3-1 verifies that the semi-conductive layer maintains its conductivity over the cable’s 5\u20138 year service life, even when exposed to mine water, minerals, and temperature cycling from underground ambient (typically 8\u201312\u00b0C) to equipment surface temperatures (up to 70\u00b0C during maximum load operation).\n <\/p>\n\n <h2 id=\"s6\">6. Insulation and Semi-Conductive Outer Layer: Preventing Corona at MV<\/h2>\n\n <p>\n The main insulation is high-purity EPR, typically 4\u20136 mm nominal wall thickness for 3.6\/6 kV cables (compared to 2\u20133 mm for 0.6\/1 kV cables). This increased thickness is necessary to reduce electric field stress to sustainable levels: a thicker insulation section reduces peak field stress from 40 kV\/mm to approximately 20\u201325 kV\/mm, well below the corona initiation threshold.\n <\/p>\n\n <p>\n Surrounding the insulation is the outer semi-conductive layer \u2014 another EPR shell with controlled conductivity, typically 0.4\u20130.6 mm thick. This layer shields the insulation from external electrical noise and prevents corona initiation from outside surfaces. It also serves a manufacturing function: it provides a smooth surface for the metal shielding layer to be applied without deforming the underlying insulation.\n <\/p>\n\n <h2 id=\"s7\">7. Independent Phase Shielding: Per-Phase EMC Protection in Multi-Core Design<\/h2>\n\n <p>\n In three-phase DM1N cables, each phase conductor is wrapped with independent tinned copper braid shielding \u2014 not a single combined shield around all three phases. This per-phase shielding design provides critical advantages: each phase shield is bonded at both cable ends to the phase’s associated earth conductor, creating independent EMC return paths for each phase. This prevents cross-coupling between phases and ensures that transient disturbances on one phase are shunted to ground through that phase’s dedicated path, rather than leaking through to adjacent phases.\n <\/p>\n\n <h2 id=\"s8\">8. Flexible Armour: Galvanized Steel + Copper Mixed Braid for Extreme Mechanical Duty<\/h2>\n\n <p>\n The flexible armour is the signature structural element of DM1N\/2M2N design. It consists of two intermixed wire types woven together in a high-density braid pattern. Galvanized steel wires (0.6\u20130.8 mm diameter, tensile strength 500\u2013700 N\/mm\u00b2) provide the mechanical crushing resistance. Pure copper wires (0.4\u20130.6 mm diameter, conductivity ~60 Million Siemens\/meter) are intermixed at a ratio of approximately 1 copper wire for every 2\u20133 steel wires.\n <\/p>\n\n <p>\n The steel component resists the deforming forces of crushing (such as a 25-tonne shuttle car or drill jumbo rolling over a cable) and cutting (such as equipment blades or shearer chain cutting edges contacting the cable). The copper component ensures that any mechanical breach that severs the armour creates an immediate short-circuit path between the severed steel wires and the internal conductors, generating a high fault current (typically 2000\u20135000 amperes) that triggers mine protection relays within 10\u201350 milliseconds.\n <\/p>\n\n <div class=\"section-divider\">\n <span class=\"section-divider-badge\">C<\/span>\n <hr>\n <span style=\"font-size:13px; color:var(--text-secondary);\">Performance, Applications & Compliance<\/span>\n <\/div>\n\n <h2 id=\"s9\">9. Medium-Voltage Testing: Dielectric Withstand and Partial Discharge<\/h2>\n\n <p>\n DM1N cables undergo specialized MV qualification testing that unshielded and low-voltage cables do not require. IEC 60502-2 specifies a high-voltage dielectric test of 10 kV AC (or equivalent DC) applied for 5 minutes to validate insulation integrity. More critically, IEC 60270 partial discharge measurement is conducted at 1.5\u00d7 rated voltage for 30 minutes, measuring corona activity within the insulation. Any significant partial discharge activity (typically > 5 pC \u2014 picocoulombs) indicates potential insulation degradation and disqualifies the cable from service.\n <\/p>\n\n <h2 id=\"s10\">10. Longwall Shearer and Drill Jumbo Cable Duty: Mechanical Stress Analysis<\/h2>\n\n <p>\n A longwall coal shearer operates by advancing across a coal face 100\u2013300 meters wide, dragging its power cable behind it across rough coal and rock floor. The cable simultaneously experiences bending (as it navigates around roof support equipment and floor obstacles), tensile loading (from drag friction), and localized crushing (from equipment weight distributed over narrow contact points). Over a typical mining shift (8\u201316 hours), a shearer cable accumulates 20,000\u201350,000 bending cycles combined with continuous tensile stress.\n <\/p>\n\n <p>\n A drill jumbo uses its cable differently: the cable is spooled on an onboard reel and paid out as the jumbo advances into newly prepared rock headings. The cable experiences high-frequency winding\/unwinding cycles (equivalent to thousands of bending reversals per shift) combined with torsional loading as the reel drums turn. Additionally, drill jumbos operate in partially supported openings where falling rock is a persistent hazard \u2014 the cable must survive direct impacts from fallen debris without insulation penetration.\n <\/p>\n\n <p>\n DM1N’s flexible armour is engineered specifically for these loading regimes. The steel-copper mixed braid distributes impact forces across the armour structure, preventing sheath penetration from rock falls or equipment contact. The copper wire component ensures immediate fault detection if catastrophic mechanical damage does occur, enabling protective equipment to de-energize the cable before dangerous arc conditions develop.\n <\/p>\n\n <h2 id=\"s11\">11. Total Cost of Ownership: When Ultra-Heavy-Duty Armour Justifies Extreme Premium<\/h2>\n\n <p>\n DM1N\/2M2N cables command a 60\u201380% material premium over equivalent 3.6\/6 kV unarmoured cables, due to the semi-conductive layer materials, independent phase shielding, and flexible armour structure. This premium \u2014 often translating to USD 5,000\u201312,000 per kilometer of cable \u2014 is justified only in applications where:\n <\/p>\n\n <ul>\n <li><strong>Catastrophic mechanical failure risk is high<\/strong>: Longwall shearers operating in poorly maintained roof conditions with frequent falls; drill jumbos in weak rock formations; equipment operating with minimal cable management infrastructure.<\/li>\n <li><strong>Production downtime cost is extreme<\/strong>: Mines where a single cable failure causes USD 200K\u2013500K+ per day in lost production.<\/li>\n <li><strong>Safety implications are severe<\/strong>: Underground coal mines where cable electrical faults could initiate methane explosions, creating not just financial loss but personnel safety hazards.<\/li>\n <\/ul>\n\n <p>\n In mining operations where cable management infrastructure is sophisticated (professional cable handling equipment, protected cable routes, regular maintenance), the ultra-heavy-duty DM1N approach may be economically unjustified \u2014 a mid-range armoured cable with standard flexible armour would provide adequate protection at lower cost. But in rough-duty continuous mining applications, DM1N’s investment in redundant protection layers and extreme mechanical durability provides insurance against the worst-case cable failure scenarios that would otherwise disable production for days or weeks.\n <\/p>\n\n <\/div>\n <\/div>\n\n \n <div class=\"doc-footer\">\n <div class=\"container\">\n <h4>Medium-Voltage Flexible Armoured Mining Cable Engineering \u2014 Technical Enquiries<\/h4>\n <p><strong>Anhui Feichun Special Cable Co., Ltd.<\/strong><\/p>\n <p>National Economic & Technological Development Zone (NETDZ), Hefei, Anhui Province 230031, China<\/p>\n <p style=\"margin-top:12px;\"><strong>Technical Engineering:<\/strong> <a href=\"mailto:Tech@feichuncables.com\">Tech@feichuncables.com<\/a><\/p>\n <p><strong>Mining Sales (MV & Extreme Duty):<\/strong> <a href=\"mailto:mining@feichuncables.com\">mining@feichuncables.com<\/a><\/p>\n <p><strong>WhatsApp \/ WeChat:<\/strong> +86 138 5512 3218<\/p>\n <p><strong>Website:<\/strong> <a href=\"https:\/\/www.feichuncables.com\" target=\"_blank\">www.feichuncables.com<\/a><\/p>\n\n <p style=\"margin-top:18px; font-size:13px; color:rgba(255,255,255,0.78);\">\n DM1N\/2M2N medium-voltage flexible armoured mining cable specialist \u2014 1.8\/3 kV to 3.6\/6 kV, Class 5 tinned copper conductors, high-purity EPR insulation, semi-conductive inner and outer layers (for MV field stress control), independent phase shielding (tinned copper braid per phase), flexible mixed-braid armour (galvanized steel + copper wires for crush\/cut resistance and anti-explosion fault initiation), heavy-duty PCP\/PUR outer sheath. Third-party MV dielectric and partial discharge testing. IEC 60502-2 compliance. 5\u20136\u00d7 O.D. bending radius despite MV construction. Applications: longwall coal shearers, hydraulic drill jumbos, extreme-duty underground mobile equipment. Chile, Peru, Colombia, Spain, Russia, Germany, Australia.\n <\/p>\n\n <div class=\"doc-ip-notice\">\n <strong>\u2605 FEICHUN PROPRIETARY MEDIUM-VOLTAGE FLEXIBLE ARMOURED CABLE TECHNOLOGY<\/strong><br>\n The Feichun DM1N\/2M2N medium-voltage flexible armoured mining cable series are proprietary and protected under Chinese Patent Law and applicable international intellectual property conventions. \u00a9 2026 Anhui Feichun Special Cable Co., Ltd. All rights reserved.\n <\/div>\n <div class=\"doc-id\">\n Document ID: FC-DM1N-2M2N-TECH-2026-R2Q7W | Published: May 2026 | Standards: IEC 60228, IEC 60502-2, IEC 60270, IEC 60811, IEC 62153-2, UNE 22513 | Valid: Spain, Chile, Peru, Colombia, Russia, Australia, EU\n <\/div>\n <\/div>\n <\/div>\n\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"DM1N and 2M2N designations represent the apex of mining cable complexity \u2014 flexible armoured cables engineered for medium-voltage (1.8\/3 kV, 3.6\/6 kV) mobile equipment operating in the most mechanically extreme underground environments. These cables are specified for longwall coal shearers, hydraulic drill jumbos, and other continuous-operation mobile equipment that simultaneously demand ultra-high mechanical durability and medium-voltage electrical capability.\nThe fundamental engineering challenge that defines DM1N\/2M2N is this: medium-voltage cables require internal semi-conductive layers and sophisticated insulation architecture to prevent corona discharge (electrical breakdown at high voltage), but they must simultaneously maintain the extreme mechanical flexibility required for cable reel winding and equipment drag duty. This convergence is far more difficult than it might appear, because the semi-conductive layers and additional insulation walls that prevent corona also inherently reduce mechanical flexibility and increase cable stiffness.","protected":false},"author":1,"featured_media":14100,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"csco_singular_sidebar":"left","csco_page_header_type":"title","csco_page_load_nextpost":"","footnotes":""},"categories":[66,464,7],"tags":[145,55162,59211,181,59221,12400,59219,59212,59207,59222,3825,59227,22314,31793,618,59225,28484,59223,59218,31731,5526,30860,59213,59208,7048,59216],"class_list":["post-14099","post","type-post","status-publish","format-standard","has-post-thumbnail","category-common-problems-encountered-in-cable-applications","category-flexible-cables-with-high-bending-life-and-fatigue-resistance","category-mining-trailing-cable","tag-epr-insulation","tag-1-8-3-kv","tag-2m2n","tag-3-6-6-kv","tag-anti-explosion-fault-initiation","tag-class-5-tinned-copper","tag-copper-wire","tag-corona-discharge","tag-dm1n","tag-drill-jumbo","tag-flexible-armoured-cable","tag-flexible-mixed-braid-armour","tag-galvanized-steel-wire","tag-iec-60270","tag-iec-60502-2","tag-independent-phase-shielding","tag-longwall-shearer","tag-medium-voltage-mining-cable-3","tag-mv-mobile-equipment","tag-partial-discharge","tag-pcp-outer-sheath","tag-pur-outer-sheath","tag-semi-conductive-inner-layer","tag-semi-conductive-outer-layer","tag-tinned-copper-braid","tag-une-22513","cs-entry"],"_links":{"self":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts\/14099","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/comments?post=14099"}],"version-history":[{"count":2,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts\/14099\/revisions"}],"predecessor-version":[{"id":14104,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/posts\/14099\/revisions\/14104"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/media\/14100"}],"wp:attachment":[{"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/media?parent=14099"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/categories?post=14099"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/feichuncables.com\/blog\/wp-json\/wp\/v2\/tags?post=14099"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":14099,"date":"2026-05-20T09:36:48","date_gmt":"2026-05-20T01:36:48","guid":{"rendered":"https:\/\/feichuncables.com\/blog\/?p=14099"},"modified":"2026-05-20T09:54:12","modified_gmt":"2026-05-20T01:54:12","slug":"dm1n-2m2n-flexible-armoured-mining-cable","status":"publish","type":"post","link":"https:\/\/feichuncables.com\/blog\/dm1n-2m2n-flexible-armoured-mining-cable\/","title":{"rendered":"DM1N\/2M2N Flexible Armoured Mining Cable"},"content":{"rendered":"\n

DM1N and 2M2N designations represent the apex of mining cable complexity \u2014 flexible armoured cables engineered for medium-voltage (1.8\/3 kV, 3.6\/6 kV) mobile equipment operating in the most mechanically extreme underground environments. These cables are specified for longwall coal shearers, hydraulic drill jumbos, and other continuous-operation mobile equipment that simultaneously demand ultra-high mechanical durability and medium-voltage electrical capability.<\/p>\n\n\n\n