I’ve had trouble using protective sleeves; could everyone recommend some?

Reference table for materials used in protective sleeves: http://bbs.hcbbs.com/thread-194878-1-1.html
Reference table for materials used in protective sleeves

| Mark | Material | Equivalent foreign grade | Maximum operating temperature | Characteristics | Applications |
|------|----------|--------------------------|----------------------------|----------------|--------------|
| A | 1Cr18Ni9Ti | 321 | 800 | Good resistance to intergranular corrosion; good weldability | Nuclear power and reactor components; petrochemical equipment; papermaking; soap manufacturing; food processing |
| B | GH3030 | – | 1100 | Nickel-based superalloy; excellent oxidation and corrosion resistance; good weldability | Furnace equipment; operations under high temperature and low pressure |
| C | GH3039 | – | 1150 | Nickel-based superalloy; better oxidation resistance than GH3030; higher operating temperature | Same as above |
| D | PtRh6 | – | 1300 | Resistant to high temperatures under oxidizing conditions; good corrosion resistance in solutions such as halogens and acids; susceptible to contamination by carbon, silicon, sulfur, etc. | Glass industry; furnaces for processing; annealing furnaces |
| E | 20 | – | 500 | Prone to oxidation; no corrosion resistance; but inexpensive | General low-temperature, non-corrosive applications |
| F | 1Cr25Ti | 446 | 1100 | Resistant to atmospheric oxidation and sulfidic atmospheres; good weldability | Petrochemical industry; metallurgy; power generation; heat treatment furnaces; incinerators |
| G | 0Cr18Ni12Mo2Ti | 316Ti | 800 | Resistant to acids, saline water, nuclear corrosion, and industrial atmospheres; good weldability | Nuclear power plants and reactors; chemical industry; pharmaceutical industry |
| H | 0Cr17Ni12Mo2Ti | 316 | 800 | Resistant to tartaric acid, phosphoric acid, and sulfuric acid; good resistance to intergranular corrosion; good weldability | Sulfate industries; pulp industry; textile industry; dye industry; soap manufacturing; pharmaceutical industry; nuclear power plants |
| HL | 00Cr17Ni12Mo2 | 316L | 800 | Ultra-low carbon stainless steel; better corrosion resistance than 316; good weldability | Same as above |
| I | H62 | – | 200 | Good strength; good thermal conductivity; easy to weld | Low-temperature, non-corrosive applications |
| J | 0Cr18Ni9 | 304 | 400 | Low-carbon stainless steel; good resistance to intergranular corrosion and weldability | Chemical industry; textile industry; papermaking; soap manufacturing; food processing; nitric acid industry; nuclear power plants |
| JL | 00Cr18Ni10 | 304L | 400 | Low-carbon stainless steel; better corrosion resistance than 304; good weldability | Same as above |
| K | 0Cr21Ni32TiAl | Incocloy800 | 1100 | Good thermal stability; oxide scale does not easily flake off; resistant to carburization and nitridation | Power plants; furnaces; crude oil and petrochemical industries |
| N | 1Cr15Ni75Fe | Incone1600 | 1100 | Nickel-chromium-iron alloy; good corrosion resistance; oxidation resistance at high temperatures; good weldability | Nuclear power plants; boilers; furnaces; heat treatment; papermaking; food processing |
| O | 00Cr15Ni60Mo16W | Hastelloy C-276 | 700 | Resistant to pitting and intergranular corrosion; good mechanical properties at high temperatures | Fine chemical industry; petrochemical industry |
| P | 1Cr25Ni20 | 310S | 1200 | Good corrosion resistance; resistant to chlorine corrosion; oxidation resistance at constant temperature | Boilers; blast furnaces; cement furnaces; crude oil and petrochemical industries; high-temperature fluidized beds; power plants |
| T | CYT101 | – | 1200 | High-performance superalloy; high strength and wear resistance; excellent resistance to sulfidation and oxidation; good weldability and machinability | Burners; heat exchangers; boilers; furnaces; papermaking; high-temperature fluidized beds; power plants |
| R | CB1 | Corundum quality | 1600 | Ceramic protective tube; resistant to high temperatures and acids/bases; can be used in corrosive media; cannot withstand impacts; prone to brittle fracture | High-temperature heating furnaces and similar applications |
| Q | CB2 | High-alumina quality | 1300 | Ceramic protective tube; similar properties to corundum tubes; but lower operating temperature | Same as above |
| M | MoSi2 | Disilicide phase | 1600 | Cerametallic protective tube; resistant to high temperatures; corrosion-resistant; good airtightness; resistant to thermal shock and erosion; but highly brittle | Petrochemical industry; natural gas industry; cement industry; metallurgy; machinery industries in high-temperature corrosive environments |
| S | SiC | Recrystallized silicon carbide | 1600 | Non-ceramic ceramic protective tube; resistant to high-temperature oxidation, corrosion, thermal shock, and erosion; but highly brittle | Metallurgical industry; glass industry; cement industry and other industrial furnaces |
| SS | SiC-Si | New type of silicon carbide | 1400 | Non-ceramic ceramic protective tube; high strength; corrosion-resistant; oxidation-resistant; wear-resistant; high thermal conductivity; able to withstand rapid temperature changes | Metallurgical industry; glass industry; cement industry and other industrial furnaces; applications requiring wear resistance |

In sulfur incineration furnaces, manufacturers generally use corundum sleeves, but their service life is not very long. I don’t have any experience with those mentioned above. In this context, two factors need to be considered: temperature and corrosion. The gases produced by the combustion of S can easily penetrate through the sleeves and cause internal corrosion of the thermocouples. Such thermocouples are usually made of precious metals, and if they break, it becomes a serious problem!

I’m from Nanjing Wanda Instrument Factory. What causes the corundum tubes to not perform well? GH3039 or MGH956 can be considered.

Corundum tubes are inherently fragile; if the incinerator is turned on and off frequently, shear forces are generated between the ceramic tube and the refractory furnace wall due to differences in thermal expansion coefficients, which can easily cause the protective tube to break. You can refer to the table on the second floor; it is what we provide to our customers. Those who have used molybdenum disilicide have seen good results. The corrosion mentioned on the 3rd floor is due to poor airtightness of the ceramic tubes; it is necessary to contact the manufacturer to select materials with better airtightness. This issue becomes significant when harmful gases such as H2 and CO enter the sleeve, as they can easily react with the filler wires.

The corundum-alumina heat-resistant and wear-resistant ceramic sleeves developed by our company have a hardness second only to that of diamond, offering high wear resistance and a long service life. YL-NT corundum refractory ceramic custom-shaped parts can be manufactured to dimensions specified by the customer, using special molds. Their main advantages include low expansion, high temperature resistance, corrosion resistance, and a long service life; they are important components for applications that require high temperatures and wear resistance. Main applications: 1. In the design of high-temperature fire-tube waste heat boilers used in desulfurization and sulfuric acid production processes, the high-temperature tube bank is a key component. In the design and manufacture of high-temperature fire-tube boilers such as sulfur incineration furnaces and Claus furnaces, the use of YL-NT corundum sleeves for thermal protection has achieved excellent results.

The main problem is that the offset deformation of the lining directly causes the ceramic sleeve to break. Things you talk about like wear resistance and hardness are useless to him