MV-90 Power Cable Extrusion Line

MV-90 Power Cable Extrusion Line

MV-90 is a general term for medium voltage power cables with a rated operating temperature of 90 ° C in North America. It is not a single model, but a product category that meets specific standards.
Letter Meaning:
MV stands for Medium Voltage, typically referring to cables with voltage levels between 2000V and 35kV.
90: The rated long-term operating temperature of the cable is 90 ° C. During a short circuit (up to 5 seconds), the conductor temperature can reach 250 ° C.
Core Standards:
The design, testing, and manufacturing of MV-90 cables mainly follow ICEA (Insulated Cable Engineers Association) and UL (Underwriters Laboratories) standards, with the most core being:
ICEA S-93-639: Used for shielding power cables.
ICEA S-94-649: Used for concentric neutral cables.
UL 1072: Safety Standard for Medium Voltage Power Cables.
Structure and Materials:
A typical MV-90 cable consists of the following structure:
Conductor: Typically annealed copper or electrical aluminum. It can be a solid, twisted, or tightly pressed twisted structure.
Conductor Shield: A layer of extruded semiconducting material used to smooth the electric field on the surface of a conductor and prevent partial discharge.
Insulation layer: Cross-linked polyethylene (XLPE) is used. This is a key material for achieving a rated temperature of 90 ° C, providing excellent electrical and thermomechanical properties.
Insulation Shield: Another layer of extruded semiconducting layer, together with the conductor shield, forms a complete shielding system with a uniform electric field.
Grounding/Shielding Layer:
Copper tape shielding: A common form consisting of a spiral wrapped copper tape.
Concentric Neutral (CN): Another more common form, consisting of bare copper wire or tinned copper wire twisted in a spiral manner outside the shielding layer, serving both shielding and grounding purposes.
Jacket: Typically made of polyvinyl chloride (PVC) or high-density polyethylene (HDPE), providing mechanical protection and moisture and chemical corrosion resistance. According to requirements, it can also be a halogen-free material.
Key Features:
High heat resistance: Operating at 90 ° C allows for higher current carrying capacity.
Excellent electrical performance: XLPE insulation has high dielectric strength and low loss.
High reliability: Mature manufacturing standards and strict testing requirements ensure its long-term operational reliability.

MV-90 Power Cable Extrusion Line

The MV-90 medium-voltage power cable extrusion production line is a complete set of equipment specifically designed for manufacturing the core components of medium-voltage power cables rated at 3.6/6 kV to 26/35 kV. This production line applies molten plastic to the conductor in a high-temperature, high-pressure, and continuous manner, ensuring uniform coating. Subsequent cross-linking processes endow the cable with excellent electrical, thermal, and mechanical properties. Given that the products are used in medium- and high-voltage applications, the requirements for the purity, uniformity, and defect-free nature of the insulation layer are extremely high. As a result, medium-voltage production lines are technologically more complex, require higher precision, and involve greater investment compared to low-voltage production lines.

Main Components

The MV-90 medium-voltage powder cable extrusion line primarily consists of the following components, arranged according to the process flow:
Pay-Off Device
Function: Supports and feeds copper or aluminum conductors. Provides stable and adjustable tension control to prevent thinning or抖动 of the conductor.
Types: Active pay-off (powered) or passive pay-off (unpowered, controlled by braking).
Conductor Pre-Heater
Function: Heats the conductor to a certain temperature (e.g., above 90°C) before extrusion.
Purpose:
Removes moisture from the conductor surface to prevent bubble formation ("microvoids") during extrusion.
Reduces the temperature difference between the conductor and the molten insulation material, minimizing internal stress and improving interfacial bonding quality.
Two or More Layers Co-Extrusion System
This is the technological core of the medium-voltage production line, typically consisting of two or more extruders and a shared die head.
Online Detection and Control System
Laser Diameter Gauge: Monitors the insulation outer diameter in real-time without contact and feeds data back to the control system to automatically adjust the extruder or traction speed, ensuring minimal thickness tolerance.
Eccentricity Gauge: Ensures the insulation layer is uniformly coated on the conductor without core shift.
Spark Tester: Detects defects such as pinholes or breaks in the insulation layer online (applicable only to cores with an outer shield, which must be grounded).
Industrial Computer/PLC: The "brain" of the entire production line, centrally controlling parameters such as temperature, speed, tension, and pressure for all equipment.
Traction Device
Function: Provides the driving force for the production line, pulling the cable forward at a constant or programmable speed. Requires extremely stable speed without vibrating.
Types: Caterpillar haul-off or dual-wheel capstan.
Take-Up Device
Function: Winds the cooled and set finished insulated core neatly onto large reels.
Requirements: Synchronized with the traction speed, constant and adjustable tension, and neat winding.

MV-90 Power Cable Extrusion Line Datasheet

Model	120+100	200+120
Screw Diameter (mm)	φ120+φ100	φ200+φ120
Screw L/D Ratio	25:1	25:1
Extrusion Amount (kg/hr)	φ120: ≤450 kg/h, φ100: ≤320 kg/h	φ200: ≤1000 kg/h, φ120: ≤500 kg/h
Inlet Wire (mm)	/	55-160
Outlet Wire (mm)	10-80	70-180
Traction (N)	/	≤32000
Production Speed(Max., m/min)	80	30
Pay-off Spool (mm)	φ1000-φ2500	φ2000-φ4200
Take-up Spool (mm)	φ1000-φ2500	φ2000-φ4200

Core Components List

Rail-mounted Motorized Pay-off Stand	2 sets
Auxiliary Caterpillar Puller	1 set
Asphalt Coating Unit	1 set
Ø200 Extruder / Ø120 Extruder	1 set
Ø120 Extruder / Ø100 Extruder	1 set
Dual-layer Extrusion Head and Cart	2 sets
Extrusion Head Vacuum Unit	1 set
Mobile Water Trough and Hot Water Tank	1 set
Stainless Steel Cooling Trough	1 set
Cable Air Wiping / Drying Unit	1 set
Length Counter / Meter Counter	1 set
Main Caterpillar Puller / Haul-off	1 set
Graphite Coating Unit	1 set
Rail-mounted Motorized Take-up Stand	2 sets
Spark Tester	1 set
Electrical Synchronous Control System	1 set

MV-90 Power Cable Extrusion Line Application

MV-90 cables are the backbone of North American medium voltage distribution networks and are widely used in:
Underground power distribution system (from substations to users);
Power supply for industrial parks;
Main power supply for commercial and large buildings;
Renewable energy projects (such as wind farms and solar power plants' collection systems).

MV-90 Power Cable Extrusion Line

The MV-90 medium-voltage extrusion line is specifically used to manufacture the core parts (insulated wire cores) of the following products:
Power transmission and distribution: Producing various medium voltage levels (such as 8.7/10kV, 8.7/15kV, 26/35kV) of transmission and distribution cables is the "main artery" of urban power grids, industrial parks, and large building power supply systems.
Specific industry requirements:
Flame retardant/fire-resistant cables: By using special materials such as halogen-free low smoke flame-retardant polyolefins, safe cables are produced for use in densely populated areas such as subways, airports, and shopping malls.
Waterproof cable: Produce longitudinal waterproof cables with a metal waterproof layer for use in rainy, humid areas or direct burial.
Mining cables: Produce mining armored cables with high mechanical strength and wear resistance.
Subsequent deep processing: The insulated wire cores produced from the CV line will also be sent to a cable forming machine for twisting (such as three core cable), and then extruded with inner sheath, armor layer (such as steel strip, steel wire) and outer sheath on the sheath line, ultimately forming a complete structure of the cable.