RQTSi5 Heat-Resistant Boiler Grate Bars: Superior Performance for Demanding Applications
Introduction to RQTSi5 Grate Bars
Boiler Philippines presents RQTSi5, our advanced heat-resistant material for boiler grate bars that outperforms traditional HT150 gray cast iron. Engineered for durability in harsh conditions, RQTSi5 offers extended service life and reduced maintenance downtime.
Key Advantages of RQTSi5 Material
- Exceptional heat resistance (up to 900°C)
- Superior thermal fatigue resistance
- Maintained high-temperature strength
- Enhanced corrosion resistance
- Excellent chlorine corrosion protection

Chemical Composition
| Component | Minimum % | Maximum % |
|---|---|---|
| Carbon (C) | 2.4 | 3.2 |
| Silicon (Si) | 4.5 | 5.5 |
| Manganese (Mn) | – | 0.7 |
| Phosphorus (P) | – | 0.1 |
| Sulfur (S) | – | 0.03 |
Mechanical Properties
| Form | Test Temperature | Tensile Strength (MPa) | Hardness (HBW) |
|---|---|---|---|
| Casting | Room Temp | ≥370 | 228-302 |
| Casting | High Temp | 67 (short-term) | – |
| Casting | High Temp | 30 (short-term) | – |
Performance Features
1. Outstanding Heat Resistance
- Withstands temperatures up to 800°C in air furnace gas (900°C at silicon upper limit)
- Forms protective SiO₂ layer that prevents oxidation
- Ideal for coal powder burners, furnace strips, and heating applications
2. Superior Thermal Fatigue Resistance
- Maintains structural integrity through heating/cooling cycles
- Low thermal expansion coefficient reduces stress cracking
- Extends service life significantly compared to standard materials
3. High-Temperature Strength
- Performs reliably at 950-1000°C combustion temperatures
- Supports heavy loads in waste incineration applications
- Resists softening and deformation under stress
4. Corrosion Resistance
- Resists acidic gases (SO₂, HCl) from combustion
- Handles alkaline ash conditions
- Optional Mo alloying for enhanced acid resistance
5. Chlorine Corrosion Protection
- Specialized protection against HCl formation
- Maintains performance in waste incineration environments
- Protective surface film prevents direct chloride contact
Applications
- Coal-fired boilers (Class II bituminous/standard coal)
- Waste incineration systems
- Annealing furnaces
- Heating furnaces
- Industrial boiler grate systems
Why Choose Boiler Philippines?
- 40+ years of boiler manufacturing expertise
- Custom formulations available to meet specific needs
- Foundry capabilities for specialized requirements
- Factory-direct pricing with quality assurance
- Comprehensive support for new installations and replacements
Product Replacement Benefits
- 1-2 year service life under normal conditions
- Reduced downtime versus standard materials
- Improved operational efficiency
- Lower total cost of ownership
Our Complete Product Range
Fuel Types
- Coal
- Biomass
- Oil
- Gas
- Electric
Boiler Types
- Steam
- Hot water
- Thermal oil
System Components
- Chain grate stokers
- Reciprocating grates
Specialty Equipment
- Autoclaves for AAC blocks
Contact Boiler Philippines Today
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