
Carbide Thermocouple Protection Tubes
Silicon carbide (SSiC / RBSiC / ReSiC) sheaths engineered for extreme temperatures, corrosive atmospheres, and rapid thermal cycling. Gas-tight options for precise, long-life measurement.
- Samples in 3–7 days
- Small batch in ~7 days
- 1 pc MOQ
Overview
Thermocouple protection tubes shield sensing elements from oxidation, corrosion, erosion and flow turbulence, enabling accurate readings and longer service intervals. Zirsec offers pressureless sintered SiC (SSiC)for highest purity and gas-tight integrity, reaction-bonded SiC (RBSiC/SiSiC) for cost-effective strength and conductivity, and recrystallized SiC (ReSiC) for ultra-high-temperature, lightweight long tubes.
- Temperature capability: up to ~1600 °C in air; higher in inert/reducing atmospheres (grade-dependent)
- Thermal shock resistance: survives rapid heat-up/cool-down cycles
- Corrosion resistance: acids, alkalis, combustion/by-product gases, molten non-ferrous
- Gas-tight options: SSiC for leak-tight sheaths and clean processes

Specifications of Protection Tubes
| End Cap Pipe | ||||
| Model | Outer Diameter (mm) | Inner Diameter (mm) | Length (mm) | Purity (%) |
| AT-THG-G1001 | 20 | 10 | 500 | 92 |
| AT-THG-G1002 | 25 | 15 | 500 | 92 |
| AT-THG-G1003 | 30 | 20 | 500 | 92 |
| AT-THG-G1004 | 35 | 25 | 500 | 92 |
| AT-THG-G1005 | 40 | 30 | 500 | 92 |
| AT-THG-G1006 | 45 | 35 | 500 | 92 |
| AT-THG-G1007 | 50 | 40 | 500 | 92 |
| AT-THG-G1008 | 55 | 45 | 500 | 92 |
| AT-THG-G1009 | 60 | 50 | 500 | 92 |
| AT-THG-G1010 | 70 | 25 | 850 | 99 |
| AT-THG-G1011 | 70 | 30 | 850 | 99 |
| AT-THG-G1012 | 90 | 63 | 1000 | 99 |
| AT-THG-G1013 | 100 | 73 | 1250 | 99 |
| AT-THG-G1014 | 110 | 80 | 1200 | 99 |
| AT-THG-G1015 | 119 | 99 | 1050 | 99 |
| AT-THG-G1016 | 120 | 95 | 1200 | 99 |
| AT-THG-G1017 | 133 | 105 | 430 | 99 |
| AT-THG-G1018 | 155 | 130 | 1040 | 99 |
| AT-THG-G1019 | 168 | 140 | 430 | 99 |
| AT-THG-G1020 | 273 | 243 | 700 | 99 |
| AT-THG-G1021 | 280 | 230 | 1500 | 99 |
| AT-THG-G1022 | 20 | 8 | 1000 | 99 |
| AT-THG-G1023 | 25 | 13 | 1500 | 99 |
| AT-THG-G1024 | 30 | 18 | 1500 | 99 |
| AT-THG-G1025 | 35 | 23 | 1500 | 99 |
| AT-THG-G1026 | 40 | 26 | 1600 | 99 |
| AT-THG-G1027 | 50 | 35 | 1600 | 99 |
| AT-THG-G1028 | 60 | 40 | 1600 | 99 |
| AT-THG-G1029 | 20 | 10 | 500 | 99 |
| AT-THG-G1030 | 25 | 15 | 500 | 99 |
| AT-THG-G1031 | 30 | 20 | 500 | 99 |
| AT-THG-G1032 | 35 | 25 | 500 | 99 |
| AT-THG-G1033 | 40 | 30 | 500 | 99 |
| AT-THG-G1034 | 45 | 35 | 500 | 99 |
| AT-THG-G1035 | 50 | 40 | 500 | 99 |
| AT-THG-G1036 | 55 | 45 | 500 | 99 |
| AT-THG-G1037 | 60 | 50 | 500 | 99 |
| Open At Both Ends | ||||
| Model | Outer Diameter (mm) | Inner Diameter (mm) | Length (mm) | Purity (%) |
| AT-THG-G2001 | 22 | 12 | 1000 | 99 |
| AT-THG-G2002 | 28 | 18 | 1000 | 99 |
| AT-THG-G2003 | 32 | 10 | 1000 | 99 |
| AT-THG-G2004 | 38 | 28 | 1000 | 99 |
| AT-THG-G2005 | 42 | 32 | 1000 | 99 |
| AT-THG-G2006 | 47 | 37 | 1000 | 99 |
| AT-THG-G2007 | 56 | 46 | 1000 | 99 |
| AT-THG-G2008 | 55 | 45 | 1000 | 99 |
| AT-THG-G2009 | 68 | 56 | 1000 | 99 |
| AT-THG-G2010 | 40 | 20 | 500 | 99 |
| AT-THG-G2011 | 30 | 18 | 500 | 99 |
| AT-THG-G2012 | 40 | 25 | 500 | 99 |
| AT-THG-G2013 | 30 | 18 | 400 | 99 |
| AT-THG-G2014 | 40 | 40 | 400 | 99 |
| AT-THG-G2015 | 70 | 25 | 850 | 99 |
| AT-THG-G2016 | 70 | 30 | 850 | 99 |
| AT-THG-G2017 | 90 | 63 | 1000 | 99 |
| AT-THG-G2018 | 105 | 70 | 1250 | 99 |
| AT-THG-G2019 | 104 | 82 | 1200 | 99 |
| AT-THG-G2020 | 120 | 100 | 1050 | 99 |
| AT-THG-G2021 | 115 | 90 | 1200 | 99 |
| AT-THG-G2022 | 128 | 90 | 430 | 99 |
| AT-THG-G2023 | 150 | 140 | 1040 | 99 |
| AT-THG-G2024 | 170 | 140 | 430 | 99 |
| AT-THG-G2025 | 270 | 240 | 700 | 99 |
| AT-THG-G2026 | 285 | 235 | 1500 | 99 |
| AT-THG-G2027 | 22 | 10 | 1000 | 99 |
| AT-THG-G2028 | 25 | 13 | 1500 | 99 |
| AT-THG-G2029 | 30 | 18 | 1500 | 99 |
| AT-THG-G2030 | 35 | 23 | 1500 | 99 |
| AT-THG-G2031 | 40 | 26 | 1600 | 99 |
| AT-THG-G2032 | 50 | 35 | 1600 | 99 |
| AT-THG-G2033 | 60 | 40 | 1600 | 99 |
Specifications of Protection Tubes
| Item | Unit | Data |
| Max Working temperature | ℃ | 1380 |
| Density | g/cm³ | ≥3.02 |
| Porosity | % | <0.1% |
| Bending Strength | Mpa | 250(20℃) |
| Mpa | 280(1200℃) | |
| Modulus of elasticity | Gpa | 330(20℃) |
| Gpa | 300(1200℃) | |
| Thermal conductivity | W/m.k | 45(1200℃) |
| Coefficient of thermal expansion | K-1×10-6 | 4.5 |
| Rigidity | 13 | |
| Acid alkaline-proof | Excellent |
FAQ
1) Which grade should I choose: SSiC, RBSiC or ReSiC?
SSiC for gas-tight, high-purity and 1600 °C air service; RBSiC for robust, cost-effective sheaths and good conductivity; ReSiC for very high-temp and long, lightweight tubes. We’ll match grade to your atmosphere and duty cycle.
2) What maximum temperature can these tubes handle?
3) Are SSiC tubes gas-tight?
4) What sizes are available?
5) Which thermocouple types are supported?
Type K, N, S, R, B are common. Select ID to allow element + insulation + thermal expansion clearance while minimizing lag.
6) How to minimize thermal shock risk?
Preheat gradually, avoid direct flame at the closed tip, maintain adequate insertion depth, and prevent cold drafts during removal. Use collars to isolate mechanical stress.
7) Alumina vs SiC: which is better?
SiC has much higher thermal conductivity and better thermal shock resistance than alumina, providing faster response and longer life in harsh atmospheres. Alumina may be chosen for certain high-purity/insulating needs.
8) Can you polish ID/OD or add protective coatings?
Yes. We offer ID/OD grinding and polishing, plus optional oxidation-resistant or acid/alkali-resistant coatings to extend life in specific chemistries.
9) How do you mount the tube?
10) What info do you need for quoting?
Customization
From design to reverse engineering, we provide free technical consulting to help upgrade your equipment. We specialize in high-precision complex parts with ±0.01mm tolerances and special coatings like acid and oxidation resistance, tailored for demanding industrial applications.
FAQ
What types of silicon carbide products does Zirsec supply?
Zirsec offers a wide range of SiC components including tubes, beams, plates, crucibles, rollers, sealing rings, and custom mechanical parts for industrial, chemical, and semiconductor applications.
Can Zirsec provide customized sizes or shapes?
Yes. We support OEM and customized production based on your drawings, specifications, or working conditions.
Do you provide samples for testing?
Yes, sample orders are available for standard items. For custom-made components, small batch samples can be produced after design confirmation.
How can I request a quotation?
Simply fill out the contact form on this page with product type, quantity, and specifications. Our sales engineer will send you a detailed quotation within 24 hours.
Does Zirsec offer technical consultation or design assistance?
Absolutely. Our engineers provide material selection guidance, structural optimization, and technical support for your specific applications.
How does Zirsec ensure product quality?
All products undergo strict inspection procedures, including dimensional accuracy, density, strength, and corrosion resistance tests before delivery.
Tell us your requirements
Our technical engineer will reply with a custom solution and quotation within one working day.


