Organized Information about RQTSi5 Heat-Resistant Material Boiler Grate Bars

I. Basic Introduction to RQTSi5

  • Full name: Ductile iron with 5% silicon content
  • Role of silicon: Mainly plays a role in improving heat resistance and corrosion resistance
  • Applicable fuels: Can be used for Class II bituminous coal, ordinary coal, etc.
  • Replacement cycle: If the fuel standard is met, the boiler can replace the grate once every 1-2 years

II. Chemical Element Composition of RQTSi5 (%)

ComponentMinimum ValueMaximum Value
C2.43.2
Si4.55.5
Mn–0.7
P–0.1
S–0.03

III. Mechanical Properties of RQTSi5

FormTest TemperatureTensile Strength σb (MPa)Hardness (HBW)
CastingRoom Temperature≥ 370228~302
Casting–High temperature short-term tensile strength: 67–
Casting–High temperature short-term tensile strength: 30–

IV. Heat-Resistant Temperature and Application Scenarios of RQTSi5

MaterialHeat-Resistant TemperatureApplication Scenarios
RQTSi5The heat-resistant temperature in the air furnace gas reaches 800°C. The silicon upper limit reaches 900°C.Used for coal powder burner, furnace strip, radiation pipe, flue gate, heating furnace intermediate pipe frame

V. Performance Advantages of RQTSi5

(I) Good Heat Resistance

The high silicon content contributes to the high heat resistance of the grate. Under high temperature conditions, silicon reacts with oxygen to form a dense silicon dioxide (SiO₂) protective film on the surface of the material, which has excellent antioxidant properties and can effectively prevent oxygen from diffusing into the material, thereby significantly improving the material’s antioxidant capacity and ensuring the grate can work stably at high temperatures.

(II) Good Thermal Fatigue Resistance

When the chain grate boiler is burning in the furnace, ordinary grates are prone to thermal fatigue due to frequent heating and cooling cycles. However, RQTSi5 has good thermal fatigue resistance, and its internal organizational structure can better adapt to changes in thermal stress when the temperature changes, making it less prone to cracking. Silicon helps reduce the thermal expansion coefficient of the material and the thermal stress caused by temperature fluctuations, thereby reducing the initiation and expansion of cracks and extending the service life of the grate.

(III) High Temperature Strength Maintenance

The surface of RQTSi5 grate sheet can withstand a combustion temperature of about 900-950 degrees, and it is also applicable when the boiler furnace temperature is about 1000°C, which is also used in some garbage incineration. It can still maintain certain strength at high temperatures, and the interaction of its alloy elements enhances the lattice structure of the material, making it less likely to soften and deform at high temperatures, thus stably bearing the load of garbage and ensuring the normal progress of the incineration process.

(IV) Good Corrosion Resistance

During incineration, various acidic and alkaline gases and substances will be produced. The alloy elements in RQTSi5 give it certain acid and alkali corrosion resistance. Silicon can improve the passivation ability of the material, and the oxide film formed on the surface can resist not only oxidation but also the erosion of acid and alkali substances to a certain extent. Other alloy elements also work synergistically to enhance the material’s tolerance to different corrosive media. Adding MO elements can further improve the corrosion resistance and acid resistance of the grate.

(V) Chlorine Corrosion Resistance

Garbage usually contains a certain amount of chlorine, which will produce highly corrosive chloride HCI during incineration. The protective film on the surface of RQTSi5 can prevent direct contact between chloride and the material matrix. At the same time, the chemical composition and organizational structure of the material itself enable it to remain relatively stable in a chlorine-containing environment, which is not easy to suffer serious corrosion damage, ensuring the service life of the grate and the normal operation of the incinerator.

VI. User Feedback and Related Services

Many users said that after replacing the RQTSi5 material boiler grate bar, the RQTSi5 grate sheet performs well not only in incinerators but also in annealing furnaces and heating furnaces, with first-class high-temperature strength and stability, so it is worth replacing. We have our own foundry and foundry workshop, and we can add different chemical elements according to customer needs to meet the needs of users, whether it is a new grate assembly or an old grate sheet replacement. For details, please feel free to contact us.

VII. Main Products and Company Information

(I) Main Products

  • Steam Boiler, Industrial Steam Generator, Coal Boiler, Chain Grate Boiler, Coal Stoker Boiler, Wood Chip Boiler, Biomass Steam Boiler, Pellet Fired Boiler, Wood Fired Steam Boiler, Rice Mill Steam Boiler, Biomass Pellet Steam Boiler, Solid Fuel Fired Boiler, Package Boiler, etc.;
  • Natural Gas Boilers, Oil Fired Boilers, Propane Steam Boiler, Diesel Steam Boiler, Gas Fired Boilers, Condensing Steam Boiler, Furnace Oil Fired Steam Boiler, 3 Pass Fire Tube Boiler, Water Tube Steam Boiler, Commercial Steam Boiler, Small Steam Boiler, High Efficiency Steam Boiler, Low Pressure Boiler, High Pressure Steam Boiler, etc.;
  • Vertical Boiler, WDR Electric Boiler, LDR Electric Boiler, Electric Steam Boiler;
  • Thermal Oil Boiler, Hot Oil Boiler, Gas Oil Heater;
  • Hot Water Boiler, Oil Hot Water Boiler, Wood Fired Hot Water Boiler, Gas Hot Water Boiler, Commercial Hot Water Boiler;
  • Chain Grate Stoker, Travelling Grate Stoker, Reciprocating Grate, Grate Bars;
  • Autoclave For AAC Blocks, etc.