Thermocouples.
Cost-effective, fast-responding and built for broad temperature ranges — thermocouples fit almost anywhere, which makes them the most widely used temperature sensor across industry.
The Most Widely Used Sensor
Five thermocouple families for every process and installation
From quick-disconnect immersion probes to drilled-bar industrial wells, tube-skin and surface assemblies, and custom multipoint multicouples — every thermocouple is built to your application and backed by our quality program.
Immersion Thermocouples
Sheathed probes with a range of terminations — J·K·T·E·N, Ø 1/25″–3/8″
Quick Disconnect Connector
A quick-disconnect connector secured to the end of the sheath allows easy assembly and disassembly using a mating connector and extension.
Fiberglass Lead Wire
Flexible fiberglass-insulated lead wire (optionally with a stainless over-braid) and an epoxy-filled transition for a direct run from process to panel. Unaffected by heat zones up to 950°F.
PVC / Teflon Lead Wire
Flexible PVC (220°F) or Teflon (400°F) insulated lead wire. PVC resists moisture and petroleum products; Teflon is unaffected by most corrosives, lubricants and outdoor weathering.
Armored Lead Wire
Fiberglass or PVC lead wire with a flexible stainless armor tube overall, hex-crimped to the transition to resist extreme physical abuse. Bare ends extend six inches past the armor for junction-box connection.
Plastic Melt Thermocouples
Plastic-melt bolt for extruders and injection-molding machines. The connection inserts directly into the melt stream, and the short immersion length keeps the tip from interfering with process flow.
Accessories & Fittings
A complete supply of fittings to mount any immersion thermocouple into an NPT opening, plus adapters that convert a probe into a plastic-melt bolt or a spring-loaded surface bayonet.
Industrial Thermocouples
Drilled-bar well assemblies — heads in Al / SS / cast iron / PP, certified NEMA-4/4X, FM, CSA, ATEX
Drilled Threaded Bar — Tapered & Straight
The most common well style. The threaded well inserts directly into process lines through pipe tees or laterals, or into tanks via half-couplings. Straight shank for longer wear; tapered to limit flow restriction.
Bar Stock Alloy Metals — Tapered
For corrosive environments or where extra strength is required. Fabricated in austenitic, ferritic or martensitic stainless steels, nickel alloys, chrome-molys and other specialty metals, with machined wrench flats.
Bar Stock — Step Down
A stepped-down shank gives a reduced wall thickness over the last 2 1/2″ of well length, improving the thermocouple element's response time. Shorter wells use the 1/2″ step for the entire shank.
Socket & Weld-In Bar Stock
For high-temperature, high-pressure service — most often steam — where leak-proof permanent connections are mandatory. Socket wells insert via tees or branch lines; weld-in wells weld directly into heavy-wall tanks.
Drilled Flange — Tapered, Straight, Stepped
Forged flanges in many sizes, ratings and facings mate to existing process flanges in pipelines or welding-neck flanges on reactors and tanks. Available in raised-face, flat-face and ring-joint, with optional full-penetration welds.
Van Stone — Tapered & Straight
Machined from a single piece of bar stock with a neck matching a 1″ or 1 1/2″ flange face, sandwiched between the vessel flange and a slip-on flange. This eliminates weld stress and lets the slip-on flange be a less expensive material.
Tube Skin Thermocouples
Tube-wall temperature for petrochemical, boiler and super-heater tubes
Made of metal-sheathed, MgO-insulated thermocouple wire (CERAMO®), tube-skin runs vary from a few feet to over fifty. Heat shields curve around the pipe and over the junction to prevent heat loss for a more accurate reading, while expansion loops compensate for thermal growth and weld clamps add security. Available with a weld pad shaped to the tube or a knife edge for fast response, and terminated with lead wire or sealed head extensions — fabricated to your installation drawings.
Tube Skin Assemblies
For monitoring surface temperatures on boilers, super-heaters and heat-exchanger tubes — custom-shaped with expansion loops, weld clamps and heat shields as required.
Surface Mount Thermocouples
Gasket, bayonet, tube-skin and magnetic styles for surface measurement
Gasket Thermocouples
Attached to a welded stud or with a nut and bolt; the measuring junction is effectively the entire gasket area. Most often used to monitor surface temperature of machinery and engines.
High Temperature Gasket
A CERAMO® tip on the gasket gives a higher temperature range and a more durable, bendable construction. Sheath extends to any length and supports an ungrounded measuring junction.
Bayonet Thermocouples
A quick twist of the bayonet locking cap gives easy installation and positive tip contact regardless of surface expansion and contraction. A variety of mounting adapters suit different machine designs.
High Temperature Bayonet
Manufactured with CERAMO® for a higher temperature range and a more durable construction, especially in moisture-prone areas, with an ungrounded measuring junction option.
Adjustable Length Bayonet
Adjustable by hand-twisting the cap, eliminating the need to stock many fixed-immersion bayonets. Available in rigid sheath or flexible armor.
Tube Skin (Surface)
Permanent-attachment tube-skin thermocouples for lightweight applications where the heavier industrial tube-skin construction isn't needed.
Magnetic Thermocouples
Measures the surface temperature of any magnetic object — ideal where quick removal is desired or the surface can't be modified. Spring-loaded with grounded or ungrounded flat tip; limited to the magnet's holding power (~400°F).
Multicouples
Multipoint temperature profiles across a tank or vessel
A multicouple arranges multiple measuring junctions at various depths so you can monitor a full temperature profile from one assembly — used in catalytic crackers, lime kilns, distillation columns and pressurized reactor vessels. Assemblies can be miniaturized to three feet with two or three sensors, or run over a hundred feet with twelve or more.
Each typically combines a junction box, the depth-staged thermocouples or RTDs, and a pipe protection well rated for the vessel's pressures and corrosives. Multicouples are custom-made to place junctions at the key points in your process, and our applications engineers can assist with the design.
Multicouple Configurations
Free-hanging, spring-loaded and multitube assemblies, miniature profiling multicouples, and averaging / swamping boxes — detailed in the Designer's Guide.
Need a specific thermocouple?
Every thermocouple is built to your application. Tell us about your process and our team will help you specify the right assembly — or browse the full product guide.