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Ceramic Thermocouple
Protection
Tubes
Tube Length
For Metric Sizes
and Molten Metal
Applications,
See OMEGATITE
at omega.com
®
650
Tube Length
Tube Length for
Tube Length for
11
⁄
16
1
and
⁄
2
" or under
1
1
7
⁄
8
"
3
⁄
4
"
7
⁄
8
"
1
13
⁄
16
"
2
Open-end tubes
also available.
Typical Physical Properties
Properties OMEGATITE® 450 OMEGATITE® 300
Composition 99.8% Al2O3 85% mullite
15% glass
Water Absorption 0.00 0.00
Specific Gravity KP/CM3 3.85 2.8
Gas Permeability Gas tight Gas tight
Compressive Strength (psi) >300,000 >190,000
Tensile Strength (psi) 30,000 18,000
Transverse Strength (psi) 55,000 27,000
Coefficient of Linear Thermal Expansion
24 to 250°C (75 to 480°F) 6.2 x 10-6 3.3 x 10-6
24 to 500°C (75 to 930°F) 7.4 x 10-6 4.0 x 10-6
24 to 1000°C (75 to 1830°F) 8.5 x 10-6 5.0 x 10-6
24 to 1500°C (75 to 2730°F) 9.8 x 10-6 -
Approximate Thermal Conductivity
(BTU)(in)/(hr)(ft2)(°F)
24°C (75°F) 230 40
800°C (1470°F) 60 25
Maximum Service Temperature 1950°C (3540°F) 1750°C (3180°F)
Dielectric Constant (1MC) 9.29 5.80
Dielectric Strength (volts/mil) >230 250
Volume Resistivity (ohm cm) 1013 10
Te Value (Volume Resistivity of 1 mega Ω cm) 800°C (1470°F) 800°C (1470°F)
Hardness (Mohs Scale) 9 7.5
Fabrication Methods Cast Cast
13
Tube Length
2"
3
Typical Chemical Analyses
Al2O3 SiO2 MgO Na2O CaO Fe2O3 Cr2O3 TiO2 MnO ZrO2 K2O
OMEGATITE® 450 99.8 0.070 0.050 0.005 0.030 0.025 <.003 0.004 0.001 - <0.001
OMEGATITE® 300 60.0 38.0 0.2 0.2 0.1 0.5 - 0.5 - - 0.700
Note: All properties are average for test specimens. Tests were performed according to ASTM specifications.
A-139
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Ceramic Thermocouple Protection Tubes
To Order Visit omega.com/ptra_ptrm for Pricing and Details
PTRA PTRM
Dimensions: inches OMEGATITE® 450 OMEGATITE® 300
Inside Outside
Diameter Diameter Tube Length* Model Number Model Number
12 PTRA-11618-12 PTRM-11618-12
1
⁄16
24 PTRA-11618-24 PTRM-11618-24
12 PTRA-564532-12 PTRM-564532-12
5
⁄64
24 PTRA-564532-24 PTRM-564532-24
12 PTRA-53214-12 PTRM-53214-12
5
⁄32
24 PTRA-53214-24 PTRM-53214-24
12 PTRA-31614-12 PTRM-31614-12
3
⁄16
24 PTRA-31614-24 PTRM-31614-24
12 PTRA-316516-12 PTRM-316516-12
3
⁄16
24 PTRA-316516-24 PTRM-316516-24
12 PTRA-1438-12 PTRM-1438-12
1
⁄4
24 PTRA-1438-24 PTRM-1438-24
12 PTRA-516716-12 PTRM-516716-12
5
⁄16
24 PTRA-516716-24 PTRM-516716-24
12 PTRA-51612-12 PTRM-51612-12
5
⁄16
24 PTRA-51612-24 PTRM-51612-24
12 PTRA-3812-12 PTRM-3812-12
3
⁄8
24 PTRA-3812-24 PTRM-3812-24
12 PTRA-7161116-12 PTRM-7161116-12
7
⁄16
24 PTRA-7161116-24 PTRM-7161116-24
12 PTRA-1234-12 PTRM-1234-12
1
⁄2
24 PTRA-1234-24 PTRM-1234-24
12 PTRA-5878-12 PTRM-5878-12
5
⁄8
24 PTRA-5878-24 PTRM-5878-24
12 PTRA-341-12 PTRM-341-12
3
⁄4 1 18 PTRA-341-18 PTRM-341-18
24 PTRA-341-24 PTRM-341-24
12 PTRA-78118-12 PTRM-78118-12
7
⁄8 1
24 PTRA-78118-24 PTRM-78118-24
12 PTRA-1114-12 PTRM-1114-12
1 1
24 PTRA-1114-24 PTRM-1114-24
300 mm PTRA-5MM7MM-12 PTRM-5MM7MM-12
5 mm 7 mm 450 mm PTRA-5MM7MM-18 PTRM-5MM7MM-18
600 mm PTRA-5MM7MM-24 PTRM-5MM7MM-24
Length: The tube lengths shown are standard lengths for a tube without any fittings. Special lengths are also available. Consult Sales.
*
Tolerance: ±5%. See omega.com for diagrams with fittings.
Important Ordering Notes
Fittings: When ordering tube with fitting specify the
fitting number (1, 2, 3) after the model number.
1⁄2 x 1⁄2" NPT: Fits tubes from 6.0 to 12.5 mm (1⁄4 to 1⁄2") OD
1.
1
2.
⁄2 x 3⁄4" NPT: Fits tubes from 8.0 to 19.0 mm (3⁄8 to 3⁄4") OD
7
3.
⁄8" x 27NS Brass Ferrule 50 mm (2") long: Fits tubes from 17.5 mm
(11⁄16") OD tubes to
Tube with any of the above fittings for an additional cost.
1
⁄8 18 PTRA-11618-18 PTRM-11618-18
5
⁄32 18 PTRA-564532-18 PTRM-564532-18
1
⁄4 18 PTRA-53214-18 PTRM-53214-18
1
⁄4 18 PTRA-31614-18 PTRM-31614-18
5
⁄16 18 PTRA-316516-18 PTRM-316516-18
3
⁄8 18 PTRA-1438-18 PTRM-1438-18
7
⁄16 18 PTRA-516716-18 PTRM-516716-18
1
⁄2 18 PTRA-51612-18 PTRM-51612-18
1
⁄2 18 PTRA-3812-18 PTRM-3812-18
11
⁄16 18 PTRA-7161116-18 PTRM-7161116-18
3
⁄4 18 PTRA-1234-18 PTRM-1234-18
7
⁄8 18 PTRA-5878-18 PTRM-5878-18
1
⁄8 18 PTRA-78118-18 PTRM-78118-18
1
⁄4 18 PTRA-1114-18 PTRM-1114-18
For Protection Tubes
with Custom Lengths or
Fittings Please Consult
Custom Engineering
Ordering Examples:
PTRM-11618-12, standard tube
with no fitting.
PTRM-11618-12-1, standard
1
⁄2 x 1⁄2" NPT fitting.
tube,
1
⁄4" OD
Discount Schedule
1 to 10 units ..........Net
11 to 24 units ........10%
25 to 100 units .......20%
101 to 500 units ......30%
Quantity discount applies to
like tubes. Other sizes,
materials, and configurations
by quotation.
A
A-140