MARSHALL / L.H. Marshall High-Temperature Industrial Thermocouples

High-temperature submersible thermocouples from MARSHALL / L.H. Marshall for molten nonferrous metals, Armor-Tip protection tubes, and lance assemblies. Professional equipment selection according to plant engineering specifications.

MARSHALL / L.H. Marshall 501-T and 701-T Submersible Thermocouples

Submersible type K chromel-alumel thermocouples from MARSHALL / L.H. Marshall deliver prompt temperature readings in molten nonferrous metals. Interchangeable tip lengths from 8 to 24 inches pair with high-temperature lead wires protected by specialized insulation sheathing.

Type K chromel-alumel calibration engineered for molten metal temperatures up to 1260 °C
Protective tip lengths spanning 8 to 24 inches (203 to 610 mm) for various bath depths
Lead wire color coding options including RY (red/yellow) and GW (green/white) jackets
Rapid thermal response time when immersed in molten aluminum, copper, brass, and bronze

Marshall R Thermocouple Reinforced Heavy-Duty Assemblies

Heavy-duty Marshall R Thermocouple assemblies from MARSHALL / L.H. Marshall withstand severe mechanical impacts and thermal stress. The reinforced construction prevents tube failure during immersion through corrosive slag layers in foundry furnaces and holding ladles.

Reinforced 501-T-R sheath assembly engineered to endure cyclic thermal shock conditions
Protective structural barrier prevents molten slag infiltration to thermocouple wires
Direct compatibility with standard 501-PGX curved lances and straight handle grips
Extended service life in heavy melting pots, transfer ladles, and holding furnaces

Marshall MTK Stationary Furnace Probes and Terminal Heads

Stationary Marshall MTK thermocouples provide continuous temperature monitoring inside melting and heat treatment furnaces. Probes spanning 8 to 36 inches assemble into robust SCH or GPH gray iron terminal connection heads coated with high-temperature protective enamel.

Extensive immersion length options from 8 inches (MTK8-6) up to 36 inches (MTK36-6)
SCH gray iron terminal heads finished with heat-resistant protective enamel coating
MTB 128 ceramic terminal blocks accommodating single and dual thermocouple circuits
High stability against furnace flue atmospheres, combustion gases, and oxidation

Marshall Armor-Tip Protective Tubes and High-Alloy Thermowells

Marshall Armor-Tip protection tubes and high-alloy thermowells shield thermocouple junctions from aggressive molten alloy erosion. Material options feature Inconel 601, Kanthal A-1, stainless steel grades 310 and 446, metal-ceramic LT-1, and dense high-purity alumina ceramics.

Inconel 601 alloy tubes engineered for extreme furnace duties up to 1260 °C (2300 °F)
Metal-ceramic LT-1 composition withstanding molten copper alloys up to 1370 °C
High-purity 96% and 99.5% alumina ceramic tubes for vacuum and induction systems
Robust isolation against molten metal wash, grain boundary oxidation, and sulfur

Marshall Straight and Curved Lance Submersible Probe Holders

Marshall Lance probe holders ensure safe and ergonomic immersion of thermocouples into ladles, crucibles, and melting vessels. Available in straight 101-PGX models up to 3048 mm and 45° or 90° curved 501-PGX configurations outfitted with protective radiant heat deflectors.

Straight lance 101-PGX series with operational lengths from 31 inches up to 120 inches
Curved 501-PGX designs angled at 45° and 90° for holding furnaces and ladles
Heat deflector shield protecting operator hands against intense molten radiation
Internal wiring conduit prevents accidental physical damage to extension cables

Marshall Porta Probe Portable Molten Metal Measurement Systems

Portable Marshall Porta Probe metallurgical systems combine an ergonomic immersion handle with a digital Fluke microprocessor indicator. The instrument captures peak melt temperatures in seconds, logs measurement data to memory, and exports temperature profiles directly to PC.

Integrated Fluke 51-II or 53-II digital meter delivering precise laboratory-grade reading
Non-volatile memory logging records measurement batches during continuous foundry shifts
Computer data logging enabled via direct PC connection for metallurgical audit reporting
Ruggedized housing design built for rigorous daily handling on foundry plant floors

L.H. Marshall Company Foundry Heritage and Temperature Instrumentation

American instrument manufacturer L.H. Marshall Company has maintained specialized engineering production since 1927, when manufacturing facilities in Columbus, Ohio were established to craft temperature sensors for molten nonferrous metals.

Over several decades of industrial implementation, MARSHALL has established an enduring reputation across foundry floors, metallurgical smelters, and thermal processing laboratories.

The equipment portfolio focuses on reliable thermal measurement in liquid aluminum, copper, brass, bronze, zinc, and magnesium alloys, where resistance to severe thermal shock and corrosive slag wash is essential for process continuity.

Architecture of MARSHALL 501-T and 701-T Molten Metal Thermocouples

Submersible thermocouples from MARSHALL / L.H. Marshall across 501-T and 701-T series utilize type K chromel-alumel elements mounted inside specialized protective tips designed for high thermal conductivity.

Standard 8-inch (203 mm) tip designs alongside extended 12, 15, 20, 24, and 30-inch variants provide safe immersion to required molten bath depths inside holding furnaces and melting crucibles.

Flexible leads featuring high-temperature insulation jackets are color-coded in RY (red with yellow) or GW (green with white) options, ensuring proper polarity connection to plant monitoring instrumentation and minimal response delay.

Marshall R Thermocouple Heavy-Duty Construction for Tough Smelting Duties

In continuous pouring operations and secondary metal melting environments, conventional sheaths often suffer physical degradation while penetrating solid slag crusts.

The reinforced Marshall R Thermocouple configuration features a strengthened structural body that preserves temperature sensor integrity under repeated mechanical shock and heavy vibration.

The design halts chemical flux penetration toward internal measuring junctions, eliminating calibration deviation and sudden circuit disconnects. These units assemble directly into 501-PGX curved lance holders and straight operator grips.

Protective Materials for Marshall Armor-Tip High-Temperature Sheaths

The Marshall Armor-Tip protection tube program incorporates advanced metallic, metal-ceramic, and ceramic materials selected for operating temperatures reaching 1870 °C.

For reducing and oxidizing furnace atmospheres, options include Inconel 601 alloy (up to 1260 °C), Kanthal A-1, stainless steel grades 310 and 446, alongside specialized gray iron for galvanizing baths.

In molten copper and brass applications, wear-resistant metal-ceramic LT-1 delivers durability up to 1370 °C, while induction and vacuum processing furnaces utilize gas-tight alumina ceramic sheaths of 96% and 99.5% purity.

Ergonomic Straight and Curved Lance Probe Immersion Systems

To protect furnace personnel against thermal radiation and liquid metal spatter, L.H. Marshall manufactures an extensive selection of Straight Lance (straight models 101-PGX, 101-EX, 101-AGX) and Curved Lance (45° and 90° angled models 501-PGX) probe holders.

Operating lengths span from 31 inches (787 mm) to 120 inches (3048 mm), allowing operators to sample temperature in large transfer ladles and mixers from a safe distance.

Handles incorporate ergonomic grips and steel heat shields, with internal wiring channels preventing accidental abrasion and heat damage to extension cables.

Porta Probe Digital Logging Units and MARSHALL Selection Support

Portable Marshall Porta Probe metallurgical systems integrate durable lance handles with precision microprocessor-based Fluke 51-II and 53-II digital meters, allowing foundry supervisors to document temperature values for each heat and transfer data logs to computers for quality audits.

SpareX provides comprehensive selection and specification support for MARSHALL / L.H. Marshall thermocouples, Armor-Tip sheaths, SCH connection heads, and high-temperature extension cables based on equipment markings, drawings, and operating conditions.

MARSHALL / L.H. Marshall and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of MARSHALL / L.H. Marshall and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.