High temperature thermocouples up to 2300°C

ARi Industries is our main provider for high temperature thermocouples. Since all our thermocouples are made to your order requirement, we can easily supply any modification or custom design based on your application. Below, you can find all information you need to compose or decipher the codes.

ARi's high temperature thermocouples are custom made and tailored to your needs. Would you like a Molybdenum sheath? Or maybe a Tantalum? Does it need to be bendable? And what length do you require? To make sure we include all of your requirements, ARi has composed a code. With this code you can easily customize the thermocouple to your wishes. If you have any questions, the Kamet sales team will be happy to help.

 

You need the following information to create an ARi high temperature thermocouple product code:

1. Style number

2. Insulation material 

3. Insert sheath length (L) in Inches

4. Sheath diameter 

5. Thermocouple wire type 

6. Junction number code 

7. Sheath material

8. Length of extension wire in Inches (if required). Standard length of 16” supplied if not specified

Symbol

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

Example

T-107

N

-  12

B

AE

(8.1)

N

-   24

 

1. Style number

T-14              Ca 15 mm bare wire leads with epoxy seal

Standard Thermocouple type T-14

T-91      
       200°C Standard male plug

Standard Thermocouple type T-91



HI-T-91  
      High temperature male plug

Standard Thermocouple type Hi-T-91

T-191
           200°C Miniature male plug

Standard Thermocouple Type T-191


T-107
           
200°C Transition with fiberglass insulated extension wire

Standard Thermocouple type T-107

 

T-77              200°C Transition with fiberglass insulated extension wire and standard 200°C male plug

Standard Thermocouple type T-77

T-99              200°C Transition with fiberglass insulated extension wire and stainless steel overbraid

Standard Thermocouple type T-99

T-31              200°C Transition with spring strain relief, fiberglass insulated extension wire

Standard Thermocouple type T-31

T-37              200°C Transition with spring strain relief, fiberglass insulated extension wire and
standard 
200°C male plug

Standard Thermocouple Type T-37

T-103            200°C Transition with spring strain relief, fiberglass insulated extension wire
with stainless steel overbraid and standard 200° male plug

Standard Thermocouple Type T-103

In applications where the cold end termination will see temperatures in excess of 200°C, standard epoxy seals may breakdown causing failure. In this case, ARi can supply a ceramic cement seal which can 
withstand temperatures up to 450°C. To specify this option, add prefix HI- in front of the partnumber selected.

2. Insulation material

 

Insulation type

Symbol

Recommended
max operating temperature

Approx melting temperature

Comments

Magnesium Oxide
(MgO)

N

1700°C

2800°C

Very hygroscopic and used mostly in compacted sheaths

Alumina Oxide
(AL2O3)

A

1550°C

2040°C

Excellent with Platinum Alloys

Hafnium Oxide
(HFO2)

H

2200°C

2790°C

Comparable to Beryllium Oxide and safe to handle

Beryllium Oxide
(BeO)

B

2200°C

2650°C

Excellent high temp thermal conductivity and resistivity. 

Beryllium is considered a toxic material and can cause
health problems if particles are inhaled.  

 

 

3. Sheath length in Inches

4. Sheath Diameter

Symbols

(A)

(B)

(D)

(E)

(F)

Standard sheath diameters

.040

.062

.125

.188

.250

For non standard sheath diameters write down the diameter in Inches. Example : .236  for a 6 mm

5. Thermocouple wire type 

Thermocouple

Symbol

Standard limits of error

Recommended temperature range

Pt10%Rh-Pt  (type S)

S

± 1.5°C or 0.25% per ASTM E230

0-1450°C

Pt13%Rh-Pt   (type R)

R

± 1.5°C or 0.25% per ASTM E230

0-1450°C

Pt30%Rh-Pt6%Rh  (type B)

B

± .5°C per ASTM E230

870-1700°C

Tungsten 5% Rhenium
Tungsten 26% Rhenium (type C)


AE

± 4.4°C (0-426°C) 
± 1% (426 - 2315°C) per ASTM E988

0-2200°C

Tungsten 3% Rhenium
Tungsten 25% Rhenium (type D)


AO

± 4.4°C (0-426°C)
± 1% (426 - 2315°C) per ASTM E988

0-2200°C

6. Junction number code

Sheath type

Thermocouple type

Junction code

Grounded

Ungrounded

Inconel 600

R, S & B

(8.1)

9

Pt10%Rh

R, S & B

8

9

Coated Molybdenum

AE & AO

N/A

(9.3)

Tantalum

R, S, B, AE & AO

(8.1)

(9.5)

Molybdenum

R, S & B

N/A

(9.4)

Molybdenum

AE & AO

N/A

(9.3)

Niobium 1% Zirc

AE & AO

(8.1)

(9.5)


7. Sheath material

 

Sheath type

Symbol

Recommended  max. temp.

Melting temp.

Allowable enviroment

Standard sheath diameter

Minimum bend radius

Inconel 600

B

1175°C

1345°C

Inert, vacuum, oxidizing

.040, .062, .125, .188, .250”

5 x diameter

Pt10%Rh

AH

1550°C

1850°C

Inert, oxidizing

.040, .062, .125”

5 x diameter

Tantalum

N

2200°C

2995°C

Inert, vacuum

.040, .062, .125”

10 x diameter

Molybdenum

O

2000°C

2620°C

Inert, vacuum, reducing

.062, .125, .188, .250”

do not bend

Niobium 1% Zirconium

AV

2200°C

2495°C

Inert, vacuum

.062, .125”

10 x diameter

Coated Molybdenum

OCR

1600°C

2000°C

Inert, oxidizing

.125, .250”

do not bend

 

Argon Backfill
In order to minimize the effects of any residual oxidation remaining inside non-compacted sheath designs, ARi standard backfill the sheath with inert Argon gas prior to sealing the cold end.

 

8. Length of extension wire in Inches 

 

Specials

Sheaths & Coating

Sheath type

 Symbol

Recommended max. temp.

Melting temp.

Comments

Tungsten

BC

2300°C

3410°C

Very high melting point and low vapor pressure for vacuum applications

Molybdenum

50% Rhenium

BE

2300°C

2550°C

Easily weldable and ductile up to 2200°C.

Suitable for inert, vacuum, hydrogen, nitrogen and amonia atmospheres

UCAR

Metal ceramic LT-1 tubes

BV

1371°C

1538°C

Good mechanical strength can withstand up to 2000° C in protected atmospheres

Moly Disillicide

BW

1700°C

Varies

Exceptional corrosive/chemical resistance

In oxidizing/reducing environments.

Coatings

Coating type

Symbol

Max. temp.

Comments

Tungsten (plasma spray)

TPL

2200°C

For resistance to graphite attach in vacuum applications. Applied to Molybdenum sheath

Boron Nitride

BN

1800°C

Non-wetting most molten metals an slags. Use in oxidizing atmospheres to 1100°C

 

Transition style thermocouples

When exotic applications require long thermocouples with expensive noble metal or refractory sheaths, ARi can supply custom made transition style thermocouples for substantial cost savings.
Thermocouples can be supplied with suitable high temperature “hot section” sheath and insulating materials long enough to reach a cooler zone in the furnace or reactor (maximum 870° C).
At this point, a brazed transition can be made to a less expensive thermocouple or compensating material with Inconel 600 or stainless steel sheath.

 Contact Kamet for specific part numbers and specifications.

 Transition Style Thermocouple

 

Bare wire thermoouple elements
ARi can supply un-sheathed bare wire thermocouple elements where quick time response and accurate measurements are critical.
Elements can be supplied in three (3) standard diameters, custom built to your length requirements.
Type R, S and B are supplied with a standard bead type junction, while tungsten rhenium types C and D (ARi type AE and AO) are supplied with the patented wire wound junction type (9.3)

 

Specify P/N

T-50994-(L)-(D)-Type

(L)

Length in Inches

(D)

Diameter (.010, .020 or .032)

(Type)

R, S, B, AE or AO

Duplex element Construction

Most thermocouple combinations with an outside sheath diameter of 1/8” (3.2mm) or larger are available in duplex element construction. (2 separate measuring circuits in 1 sheath) To specify this option, add the suffix .4 after the style number. Repeat the junction code a 2nd time and add parentheses.

Example T-91.4N-12FR(9.9)B or T-91.4B-18DAE(9.3)(9.3)O

Mating Jack
If required with any of our male plug type thermocouples (T-91, T-191 and HI-T-91) we can supply the appropriate mating jack with the assembly. To specify this modification, add (MOD) after the part number and specify “supplied with mating jack”

Teflon insulated extension wires
For designs where extension wire attachment is required, we can supply moisture resistant Teflon insulated extension wire in place of our standard fiberglass. Other insulation types can be supplied subject to availability. To specify this modification, add (MOD) after the part number and specify "With Teflon Insulated Leads" in the description.

Special limits of error
Thermocouples with R, S & B calibrations made with mineral insulated construction can be supplied with special limits of error tolerances per ASTM E-230 or Class 1 per IEC-584 subject to availability of material from stock. To specify this modification, add (MOD) after the part number and specify "Per Special Limits of Error" or "Per Class 1 Tolerance" in the description. 

Special Testing 

  • Temperature calibration
  • Radiography
  • Liquid penetrant
  • Helium leak
  • Dimensional & Insulation resistance

All ARi standard are traceable to the National Institute of Standards and Technology (NIST).
ARi’s quality management system meets the requirements of ISO9002 as certified by Lloyds Register Quality Assurance.

Related products