Fire-tube boilers are the most widely deployed industrial boiler type, and their relatively simple construction makes spare parts sourcing straightforward when you have the right supplier. AQ Process Systems stocks and sources a comprehensive range of fire-tube boiler spares, from consumable items like gaskets and packing to critical components like replacement tubes, burner assemblies, and flame safeguard systems.
Whether you are performing scheduled maintenance, an annual inspection shutdown, or responding to an emergency tube failure, we supply OEM-compatible replacement parts that meet ASME, IBR, and EN material and dimensional specifications. Our global supply network means we can source parts for virtually any fire-tube boiler make and model in operation today.
All tube materials are supplied with Mill Test Certificates (MTC) per EN 10204 3.1. Gaskets, seals, and refractory materials are sourced from approved manufacturers with full material traceability.
| Component | Specification | Description |
|---|---|---|
| Tubes & Tube Sheets | ||
| Fire Tubes / Smoke Tubes | SA 178 Gr. A/C, SA 214 | OD 50.8 to 76.2mm | ERW or seamless | Replacement boiler tubes for 2-pass, 3-pass, and 4-pass configurations. Cut to length or supplied in mill lengths. |
| Tube Sheets (Front & Rear) | SA 516 Gr. 70 | Drilled & machined to OEM pattern | Front and rear tube sheets, drilled, faced, and ligament-checked to original equipment specifications. |
| Stay Tubes & Stay Rods | SA 178 / SA 36 | Threaded or welded ends | Structural stays that brace the flat surfaces of the boiler shell against internal pressure. |
| Gaskets & Seals | ||
| Manhole Gaskets | Spiral wound SS 304/graphite | ASME B16.20 | High-pressure gaskets for boiler shell manhole openings. Spiral-wound or corrugated metal types. |
| Handhole Gaskets | Compressed fibre or metallic | Custom sizes | Gaskets for handhole inspection ports, available in standard and custom dimensions. |
| Flange Gaskets | Spiral wound, PTFE, graphite | ASME B16.20/B16.21 | Flange gaskets for all boiler nozzle connections, steam, feedwater, blowdown, and instrumentation. |
| Door Seals & Packing | Ceramic rope, graphite rope | Various diameters | Combustion door seals, access door gaskets, and valve stem packing. |
| Burner Components | ||
| Burner Assemblies | Gas, oil, or dual-fuel | OEM-compatible | Complete burner replacement units or sub-assemblies for gas, oil, and dual-fuel fire-tube boilers. |
| Burner Nozzles & Diffusers | Stainless steel | Various capacities | Fuel nozzles, air diffusers, and mixing plates, critical for combustion efficiency and emission control. |
| Flame Scanners / UV Sensors | UV, IR, or UV/IR combined | 4-20mA output | Flame detection sensors for burner management systems, UV, infrared, and combination types. |
| Ignition Electrodes & Transformers | Ceramic-insulated | 6kV, 15kV | Spark ignition electrodes and high-voltage ignition transformers for burner startup sequence. |
| Refractory & Insulation | ||
| Castable Refractory | Low-cement, high-alumina | 1400 to 1600°C rated | Monolithic castable refractory for combustion chambers, rear turnaround chambers, and burner throats. |
| Firebricks | High-alumina or chrome | Standard and custom shapes | Shaped refractory bricks for dry-back boiler rear chambers and burner quarl linings. |
| Ceramic Fibre Blankets | 128 kg/m³ density | 1260°C rated | High-temperature insulation blankets for outer casing, access doors, and observation ports. |
| Safety Devices | ||
| Safety / Relief Valves | ASME Sec I certified | Flanged or threaded | Spring-loaded safety valves, ASME Section I Code-stamped. Set pressure tested and certified. |
| Low-Water Cutoff Switches | Float or probe type | SPDT/DPDT | Primary and secondary low-water cutoff devices, float-operated or electronic probe type. |
| Pressure Relief Valves | Bronze or cast steel | ASME VIII | Supplementary pressure relief protection for feedwater systems and auxiliary vessels. |
| Instrumentation & Controls | ||
| Water Level Gauges | Reflex or transparent | Bi-colour option | Direct-reading water level gauges, reflex type, transparent type, or bi-colour for high visibility. |
| Sight Glasses | Borosilicate | Round or rectangular | Combustion observation sight glasses, heat-resistant borosilicate glass with protective frames. |
| Pressure Gauges | Bourdon tube | 0 to 40 bar range | DN63, DN150 | Boiler drum pressure gauges, glycerine-filled option for vibration dampening. |
| Flame Safeguard Controllers | Honeywell, Siemens, Fireye compatible | Burner management system (BMS) controllers and programmer modules for safe burner operation. |
| Valves & Fittings | ||
| Blowdown Valves | Quick-opening or slow-opening | CS/SS | Surface and bottom blowdown valves for TDS control and sludge removal. |
| Feedwater Check Valves | Swing or piston type | CS/SS | ASME B16.34 | Non-return valves preventing backflow from boiler to feedwater line. |
| Main Steam Stop Valves | Gate or globe | Flanged | ASME B16.34 | Primary steam isolation valves, gate or globe type with OS&Y (outside screw and yoke). |
Parts are matched to OEM material specifications and dimensional tolerances. Please provide the equipment manufacturer, model number, and serial number (if available) for precise part identification. Mill Test Certificates (MTC) supplied with all tube materials per EN 10204 3.1.
The most frequently replaced fire-tube boiler parts include tubes (due to corrosion, erosion, or overheating), gaskets and seals (replaced during every inspection shutdown), burner nozzles and diffusers (wear items), refractory lining (erosion from combustion gases), flame scanners, ignition electrodes, safety valves (require periodic testing and recertification), and water level gauge glasses.
You need the tube material grade (typically SA 178 Gr. A or SA 214), outside diameter (commonly 50.8mm or 63.5mm), wall thickness, and length. These specifications are found on the boiler datasheet, original tube MTCs (Mill Test Certificates), or by measuring an existing tube. AQ Process Systems can also identify tubes from the boiler make, model, and serial number.
Yes. We supply OEM-compatible replacement parts for all major fire-tube boiler manufacturers including Thermax, Cleaver-Brooks, Miura, Forbes Marshall, Bosch, Hurst, Johnston, Fulton, and others. Parts meet the same material and dimensional specifications as the original equipment.
Yes. AQ Process Systems is a global supplier based in Mumbai, India with operations in Miami. We export boiler spares worldwide, all tube materials include Mill Test Certificates (MTC) per EN 10204 3.1, and safety valves are supplied with ASME Section I Code stamps as required.
Standard items like gaskets, packing, sight glasses, and common tube sizes are typically available within 1 to 2 weeks. Custom or OEM-specific items such as machined tube sheets, burner assemblies, and flame safeguard controllers may require 3 to 6 weeks depending on the manufacturer. Emergency supply can be arranged for critical breakdowns.
Both. We can supply complete burner replacement assemblies (gas, oil, or dual-fuel) as well as individual burner components, nozzles, diffusers, flame scanners, ignition electrodes, transformers, and combustion air dampers. We supply from the original burner manufacturers or approved equivalents.
Share your equipment make, model, and part numbers, we respond within 24 hours.