Mineral Insulated Metal Sheathed Cable

What is MI Cable?

Mineral Insulated Metal-Sheathed Cable is a solid body with high density formed by multiple drawings of electric heating alloy wire (Heating Element), inorganic mineral insulation and metal casing. It can meet the needs of high temperature conditions and large heating power (up to 250W/m), and the maximum temperature can reach 600°C; the conductor resistance value ranges from 0.002Ω/m to 36Ω/m, and has excellent mechanical strength and corrosion resistance. Mainly used in nuclear industry, construction industry, metal manufacturing industry, tank and container heating, High-Temperature Industrial pipeline heating, process medium anti-condensation and viscosity reduction, various industrial Electric Heaters, etc. It has been proven in international use for more than four decades.

MI Cable Classification

MI cable is a cable that uses metal (such as copper, copper-Nickel Alloy, etc.) as the conductor, magnesium oxide mineral insulation material as the insulator, and metal materials (such as copper, copper-nickel, stainless steel, alloy materials) as the sheath. If necessary, a layer of plastic outer sheath or low-smoke Chimney-less outer sheath can be extruded outside the metal sheath.

Mineral Insulated Copper Sheathed Cable

It can meet the needs of high temperature conditions and long-distance tubeline heating. The maximum withstand temperature can reach 250℃; for occasions requiring anti-corrosion or buried applications, a high-density polyethylene HDPE outer sheath must be added, the maximum withstand temperature can reach 90℃; and it has excellent mechanical strength.

Mineral Insulated Copper-nickel Sheathed Cable

Copper-nickel sheathed series mineral insulated cables can meet the needs of high temperature conditions and long-distance tubeline heating. Its maximum temperature can reach 400℃; mineral insulated cable has excellent mechanical strength and corrosion resistance.

Mineral Insulated Stainless Steel Sheathed Cable

Stainless steel sheathed series mineral insulated cables can meet the needs of high temperature conditions and large heating power (up to 269W/m). This series of cables can withstand a maximum temperature of 650°C; the mineral insulated cables have excellent mechanical strength and are corrosion-resistant.

Mineral Insulated 825 Alloy Sheathed Cable

The 825 all-gold sheathed series of mineral insulated cables can meet the needs of high temperature conditions and large heating power (up to 269W/m). This series of cables can withstand a maximum temperature of up to 800°C; the conductor resistance ranges from mineral insulated cables to excellent mechanical strength, high temperature resistance and corrosion resistance, and is suitable for various explosion-proof occasions and special areas.

Technical Parameter

Model	Name	Nominal Section (mm ²⁾ )
MI/TT	Copper sheathed tube, copper core cable	0.4-20
MI/TK	Copper sheathed tube, constantan core cable	0.4-20
MI/GT	Stainless steel sheathed, copper core cable	0.4-20
MI/GK	Stainless steel sheathed, constantan core cable	0.4-20
MI/GN	Stainless steel sheath, chrome 20 nickel 80 core cable	0.4-20

Model	Specification （mm²）	Sheath Thickness （mm）	Insulation Thickness （mm)	Finished Product Outer Diameter （mm）	Maximum Length of Single Root （m）	Pressure Resistant （v）	Operating Temperature （℃）	Maximum Current （A）
MI/TT MI/TK MI/GT MI/GK MI/GN	0.4	0.39	0.65	3.0	300-350	1500	250-800	23
	0.7	0.38	0.70	3.2	280-320	1500	250-800	32
	1.0	0.385	0.75	3.5	250-320	150n	250-800	41
	1.5	0.420	0.85	4.0	200-250	1500	250-800	50
	2.5	0.460	0.9	5.0	100-200	1500	250-800	67
	4.0	0.50	1.0	6.0	100-150	1500	250-800	75
	6.0	0.85	1.5	8.0	50-80	1500	250-800	90
	8.0	1.10	2.0	10	30-50	1500	250-800	100
	10	1.25	2.3	12	20-30	1500	250-800	120

Parameter		Copper core copper sleeve structure	Constantan core copper nickel sleeve structure	Nickel chromium stainless steel sleeve structure
Heating Power（W/m）		5-30	20-100	50-250
Max. Surface Temperature (℃)		200	400	650
Max. Operating Temperature（℃）		150	350	500
Outer Diameter （mm）	Single Core	φ3-6	φ3.5-6	φ3.5-6.5
Outer Diameter （mm）	Twin Core	φ6-10	φ6-11	φ5.5-11
Material（mm）	Conducting Core	Oxygen-free Copper	Constantan, PVC Alloy	Nichrome
	Insulation Materials	Magnesium Oxide Powder	Magnesium Oxide Powder	Magnesium Oxide Powder
	Metal Sheath	Electrical Pure Copper	Copper-nickel Alloy	Stainless Steel

Length: ±2%;
Resistance Value Tolerance: ±10%;
Voltage Resistance: Heating cable resistance: 1500VAC/1min; Heating element voltage resistance: 1200VAC/1min;
Insulation Resistance: finished product test -100MΩ/500VDC;
Impermeability: After the entire cable (including Connectors) is immersed in water for 12 hours, the insulation resistance shall not be less than -100MΩ/500VDC.

Single core, maximum operating voltage 400V

Normal Temperature 20℃ Resistance per meter( Ω/m)	Cable OD (mm)	Maximum length without joints (m)
2.50	3.5	340
1.60	3.5	340
1.00	4.0	260
0.630	4.5	200
0.400	5.0	165
0.250	5.3	150
0.630	4.0	260
0.400	4.0	260
0.250	4.5	200
0.160	4.0	260
0.063	4.0	260
0.040	4.0	260
0.025	4.0	260
0.017	4.0	260
0.011	5.0	165
0.007	5.3	150
0.004	6.0	120

Single core, maximum operating voltage 600V

Normal Temperature 20℃ Resistance per meter (Ω /m)	Cable OD (mm)	Maximum length without joints (m)
6.56	4.0	260
5.25	4.0	260
4.27	4.0	260
3.28	4.0	260
2.79	4.0	260
2.30	4.0	260
1.95	4.0	260
1.64	4.0	260
1.25	4.0	260
0.984	4.0	260
0.820	4.0	260
0.658	4.0	260
0.558	4.0	260
0.492	4.0	260
0.328	4.0	260
0.262	4.0	260
0.230	4.0	260
0.197	4.0	260
0.164	4.0	260
0.131	4.0	260
0.118	4.0	260
0.098	4.0	260
0.088	4.0	260
0.068	4.0	260
0.052	4.0	260
0.043	4.0	260
0.033	4.0	260
0.021	4.0	260
0.013	4.0	260
0.008	5.0	165
0.005	5.6	130
0.003	6.4	100
0.002	7.2	60

Single core, maximum operating voltage 800V

Normal Temperature 20℃ Resistance per meter (Ω /m)	Cable OD (mm)	Maximum length without joints (m)
10.0	3.2	400
6.3	3.2	400
4.0	3.2	400
2.5	3.4	360
1.6	3.6	320
1.0	3.9	270
0.63	4.3	220
0.40	4.7	190
0.25	5.3	150
0.16	6.5	95

Dual cores, maximum operating voltage 300V

Normal Temperature 20℃ Resistance per meter (Ω /m)	Cable OD (mm)	Maximum length without joints (m)
36.1	3.0	460
29.5	3.0	460
24.6	3.5	340
19.7	3.5	340
16.4	3.5	340
13.1	3.5	340
9.02	4.0	260
8.20	4.0	260
6.56	4.0	260
5.58	4.0	260
4.59	4.0	260
3.74	4.0	260
3.28	4.0	260
2.30	4.0	260
1.97	4.0	260
1.64	4.0	260
1.31	4.5	200
0.984	4.5	200
0.820	4.0	260
0.656	4.0	260
0.492	4.0	260
0.410	4.0	260
0.328	4.0	260
0.279	4.5	200
0.230	4.5	200
0.164	4.0	260
0.131	4.0	260
0.115	4.5	200
0.098	4.5	200

Advantages of MI cables

Because its structure is inorganic, MI heating cable has a long life, is not easy to age, and has high compressive strength. Because its outer sheath is a metal sheath, it determines that it will not age for a long time and can operate at high temperatures for a long time. Therefore, MI cable mineral insulated high temperature heating cable has absolute advantages.

Fire protection: MI cables are made of non-polar materials, making it impossible for the cable to burn, let alone support combustion or release toxic and harmful gases at high temperatures.
Explosion-proof: MI cable is a solid structure composed of seamless metal sheath and tightly compacted mineral insulation material, which fundamentally prevents the intrusion of flammable gases and flames. It is a true explosion-proof cable.
Anti-corrosion: The sheath of MI cable is a seamless metal sheath. When selecting, a suitable metal outer sheath can be selected according to the actual conditions of the workplace, which fundamentally prevents the cable from being corroded.
Anti-penetration: The sheath of the MI cable is a seamless metal sheath, so neither liquid nor gas can penetrate into the interior of the cable.
Radiation protection: MI Heating Cables are made of non-polar materials, so the performance indicators of the cable will not change when working in places with radiation.
Long life: The characteristics of the materials that make up the MI cable determine that the cable does not have the problem of insulation aging and has long-term stability.
Good flexibility: MI cables are softened at the factory and have excellent flexibility and can be bent freely. It can be laid in narrow spaces and irregular-shaped equipment, which provides great convenience for installation and construction, and the lines are beautiful after installation.
High mechanical strength: Due to the inherent characteristics of the structure of the MI cable, the cable can withstand severe mechanical damage and can still work normally when the cable diameter is deformed by one-third. Because the heating method of this cable is a series-connected resistance electric heating element, the heating is uniform and the temperature difference along the entire length is extremely small.
High heating power: generally, 50W/M~250W/M. This cable does not have the risk of freezing due to stoppage of steam supply like steam heating pipelines. Just turn on the power when needed and does not require regular maintenance.
Low temperature resistance: It is not brittle and broken when constructed at low temperatures, and is easy to construct and maintain in winter.
Low project cost: MI cable mineral insulated high-temperature heating cable is small in size, so the amount of insulation material will not be increased when laying, and the boiler and water treatment system for steam and water heating are omitted, and the construction is convenient and fast. This directly reduces the cost of the project.
Low operating costs: The heating system composed of mineral insulated high-temperature heating cables can be controlled remotely, remotely and automatically, and can ensure accurate and timely supply of the heat required by the heated object through the temperature control part, so there is no additional heat losses and redundant operating personnel, ensuring minimal operating expenses.
Low maintenance costs: The heating system composed of mineral insulated high-temperature heating cables has a simple structure, long life, and high reliability, which reduces the components and time required for maintenance. It can even be used normally without maintenance in places where the working environment is not particularly harsh.

In short, mineral insulated cables have incomparable advantages over various heating technologies and methods used in the past in places with harsh conditions such as explosion-proof, fire-proof, waterproof, anti-corrosion, and radiation resistance, and to replace traditional steam and water heating.

MI Cable Usage

Rtd and Thermocouple Sensors from MI are widely used in metal heat treatment, solid waste incinerators, sintering powder metals, firing ceramic materials, gas or oil furnaces, fuel Heat Exchangers, box furnaces and nuclear or hydrocarbon-based energy plants.

Petrochemical Industry

Container heating, process pipeline insulation, storage tank heating and insulation, crude oil pipeline wax removal and blockage removal.

Heating and Insulation

Large area heating of buildings, factories, warehouses, agricultural and gardening greenhouses, constant temperature-controlled poultry breeding heating.

Outdoor Equipment and Facilities in Cold Areas

Mechanical equipment, airstrips, TV transmission towers, culverts, valves, gates, transportation hub facilities, schools, hospital open-air steps, intermittent liquid Pumps. Railway tracks, track forks and other places that require heating and insulation.

Oil Platforms and Ocean-going Vessel Moorings

Deck anti-condensation, cabin heating, fluid tube heating and insulation, and mechanical equipment insulation. Mi cable's insulation will not burn, making it ideal for applications where a fire would be catastrophic. Medical equipment, power plants, and oil rigs are examples where installing MI cables will make their operations safer.

Combustion Preheating Device

Nuclear power plant reactor preheating, oil boiler preheater, gas device preheater. MI covered cable's metal sheath helps protect the Thermocouple Wire from oxidation when used in chemically active or humid environments. Corrosion resistance makes MI cables ideal for use in areas where failure and replacement may be hazardous or even impossible. For example, MI cables are used in nuclear power plants to monitor core temperature. It can be very dangerous if the Temperature Controller does not receive accurate readings, and repairing or replacing cables in that environment is very difficult.

Heat Treatment or Sintering

The mineral filler in Mi cables provides excellent non-reactive insulation, preventing the thermocouple wires from coming into contact with each other or with corrosive substances such as oil, solvents or water. This helps ensure that the thermocouple probe remains accurate, which is critical for applications such as heat treating or sintering, where the quality of the product can be adversely affected by temperature fluctuations.

Due to mineral insulation, MI cables can operate in high temperature conditions without loss of accuracy. This makes them ideal for use in kilns, firing ceramics or heat-treating metals, or any high temperature process. MI cables maintain their accuracy even during and after exposure to high temperatures, making them ideal as thermocouple probes in these operations.

Content

Mineral Insulated Metal Sheathed Cable

What is MI Cable?