Mineral-Insulated-Metal-Sheathed, MIMS, MI Cable or MgO thermocouples. They are referred to by several names and are used in thousands of different applications. They are highly versatile sensors for use in process temperatures up to 2400°F (1315°C) and a wide range of atmospheres and conditions. Of all the thermocouple construction types, these are by far the most adaptable and configurable. A virtually limitless number of combinations of can be achieved with the many combinations of element type, insulation, sheath material, sheath diameter, junction type, accessories, and fittings.

MgO Thermocouples have a sheath is a seamless, hermetically-sealed metal tube, tightly packed with Magnesium Oxide powder. Thermocouple wires run through the metal tube parallel and isolated from each other suspended within the MgO powder which has a high dielectric strength. These thermocouples are durable, malleable & and have a quick response to temperature fluctuations. In addition, they are very flexible, easily bent and formed into shape. MgO cable can be bent at radii as small as 2X the outer sheath diameter with no signal or performance degradation.

The MgO sheath can be welded or brazed to a surface and provides shielding for the thermocouple wires inside, protecting them from Radio Frequency Interference (RFI) and Electromagnetic Interference (EMI). This is in addition to the protection of the thermocouple wires from intense heat, cryogenic temperatures, oxidation, corrosion, moisture, thermal shock, and high pressure.

Lengths of MgO cable can also be used as extension wire in harsh environments.

CEL only supplies MgO thermocouples that meet or exceed special limits of error.

Cleveland Electric Laboratories builds MgO thermocouples to order as a stand-alone product or with added protection tubes, process fittings, transitioned to soft wire or in thermowells. Termination on the cold end includes industry-standard plugs/jacks, bare leads, terminal blocks, or protection heads. For the hot end, the junctions may be grounded, ungrounded or an exposed junction and can also be made with weld pads, screw terminals and others. These optional accessories are in stock and can be configured and built to suit your exact needs.

Metal-Sheath (MgO Thermocouples) Industrial Thermocouples
MgO Thermocouples are versatile, flexible sensors used in process temperatures ranging from -320F to 2400F. With an offering of calibrations, sheath materials, diameters, customer lengths and terminations, our customized MgO’s often serve as work/load sensors as well as for overall temperature uniformity of the furnace chamber.

Applications

Heat Treating, Forging, Annealing, Hardening, Engine Testing and Monitoring, Specialty Metals Processing, Oil & Gas Refining, Exploration & Extraction

Technical Data

Calibration: B, E, J, K, N, R, S, & T
Sheath Diameters: 0.010” – .750”
Sheath Materials: Inconel, Stainless Steel & Platinum
Junction Construction: Grounded, Ungrounded & Exposed
Extension Leads: Multiple Extension Lead Options
Termination: Multiple Connector & Termination Head Options
Hardware: Multiple Mounting Hardware Options
Certification: Individual or Lot Certification; Special Limits of Error

Small Diameter Rapid-Response Thermocouples

Very small, swaged sheath diameters that provide accurate temperature measurement and quick response times.

MgO thermocouples are available with overall sheath diameters as small as .020” for fast response. For increased sensitivity, we are able to reduce the outside diameter as necessary in your process. Our reduced-tip thermocouples are made to order by calibration, standard diameter and length, reduced diameter and length, junction style, transition and/or termination.

Applications

Turbine Testing, Laboratories

Technical Data

Calibration: B, E, K, N, R & S
Junction Construction: Grounded, Ungrounded & Exposed
Extension Leads: Multiple Extension Lead Options
Termination: Multiple Connector & Termination Head Options
Certification: Individual or Lot Certification; Special Limits of Error

Reduced diameter tips are also available in this configuration.

Base Metal Thermocouples

Base Metal Thermocouples are tried and true temperature measurement devices that have stood the test time. Rugged, durable industrial thermocouple assemblies designed for use in the most severe process environments and temperatures up to 2300°F (1260°C). Base metal thermocouples are the most commonly used category of thermocouples and are made of common and inexpensive meals such a Nickel, Copper and Iron.

  • Twisted and welded or butt weld junctioning
  • Straight or bent assemblies
  • Additional sheathing for extreme environment like those found in molten salt baths
  • CEL only supplies MgO thermocouples that meet or exceed special limits of error.

Cleveland Electric Laboratories builds Base Metal Assemblies and Elements to order with added protection tubes, process fittings, transitioned to soft wire or in thermowells. Termination on the cold end includes industry-standard plugs/jacks, bare leads, terminal blocks, or protection heads. For the hot end, the junctions may be grounded, ungrounded or an exposed junction either twisted and welded or in a butt weld configuration. These optional accessories are in stock and can be configured and built to suit your exact needs.

Base Metal Assemblies (BMAs) and Base Metal Elements (BMEs) are designed for the most severe environments. As noted by name, Base Metal includes Type E, J, K, M, N and T calibrations. Offered in a wide variety of protection tubes and hardware, our Base Metal products offer durability, accuracy and response for your unique application.

Applications

Steel Production, Waste Incineration, Heat Treating, Salt Baths, Rotary Kilns

Technical Data

Calibration: E, J, K, N, M & T
Junction Construction: Grounded, Ungrounded & Exposed
Extension Leads: Multiple Extension Lead Options
Termination: Multiple Connector & Termination Head Options
Hardware: Multiple Mounting Hardware Options
Certification: Individual or Lot Certification; Special Limits of Error

Immersion Tips & Lance Handles

Immersion Tips are small expendable thermocouples that are inserted into the end of a Lance Handle, which often also have a receptacle. The lance pipe with the thermocouple tip is then immersed into molten metal for 4-5 seconds to simultaneously measure the temperature and retrieve a sample in the receptable. This sample is then tested to determine the composition of the metal. The Immersion Tip is then discarded and a new tip is affixed for the next test.

Used for direct temperature sensing in molten metals applications: brass, copper, aluminum, lead and other non-ferrous metals. Durable. Reusable. Accurate.

Applications

Non-Ferrous Molten Metals

Technical Data

Calibration: K
Sheath Diameters: ½” OD
Sheath Materials: 446SS
Accuracy: Special Limits of Error
Extension Leads: Multiple Extension Lead Options

Resistance Temperature Detectors (RTDs)

Resistance Temperature Detectors (RTDs) use the relationship between a change in temperature and the resulting change in resistance of one or more fine metal wires or films that are wrapped around a ceramic or glass core. Multiple wire configurations are used to minimize the effect of a change in the resistance of the lead wire.

Cleveland Electric Laboratories typically supplies 3-wire Platinum RTDs. Platinum has the most stable resistance-temperature relationship over the largest temperature range and is also not susceptible to corrosion or degradation. There are several options in regards to accuracy or class of RTD.

Highly accurate with fast response time & an excellent degree of repeatability. Suitable for a many temperature measurement & control applications up to 1200°F.

Typically supplied with platinum sensing elements, Resistance Temperature Detectors (RTDs) measure the change in electrical resistance to determine temperature. For temperature sensing applications under 750°F, RTD’s provide excellent long-term stability and accuracy.

Applications

Chemical Plants, Refineries, Process Validation

Technical Data

Termination and Hardware: Fittings, Heads & Other Terminations.
Certification: Individual or Lot Certification; Special Limits of Error

Refractory Metal Assemblies

Type “C” is one of several thermocouple wire combinations of Tungsten and Rhenium that are commonly referred to as Refractory Metals. Tungsten-5% Rhenium vs Tungsten-26% Rhenium, or Type “C”, may be used at temperatures up to 4200°F (2315°C). These Refractory metals may be used at extremely high temperature but with some constraints. Tungsten has no oxidation resistance and must be used in vacuum, hydrogen, or a totally inert gas. Type “C” thermocouples used in other atmospheres must be assembled as a sealed assembly purged with Argon.

Used in vacuum or inert atmosphere applications up to 4200°F, our Type C thermocouples may be supplied with a variety of sheath options, including alumina, molybdenum and tantalum. Additional sheath coating are available to extend service life. These high-heat sensors offer an accurate temperature measurement solution for extreme temperatures.

Industrial Thermocouple Additional Services

  • Calibration & Certification Lab

  • Repair & Recalibration

  • Exchange Programs

  • Engineering Services

  • Value-added Services
  • Product Tagging & Serialization
  • Product Kitting

The Highest Standards in High Temperature Thermocouples

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