Once-through steam generators operate in some of the most demanding environments, from heavy oil recovery fields to offshore platforms. Their continuous coil design means tube integrity is paramount, as a single tube leak can take the entire unit offline. AQ Process Systems sources and exports replacement coil tubes, headers, and all auxiliary components.
We source OTSG-specific parts including high-pressure alloy coil tubes, outlet headers, burner components rated for high-TDS feedwater service, and specialised instrumentation for steam quality monitoring. All parts are compatible with major OTSG manufacturers.
For enhanced oil recovery operations, we understand the urgency of spares supply, downtime directly impacts oil production. Our supply network supports rapid turnaround for critical OTSG components.
| Component | Specification | Description |
|---|---|---|
| Coils & Headers | ||
| Coil Tubes | SA 106 Gr. B/C, SA 335 P11/P22 | High-pressure rated | Replacement coil tubes, straight or pre-bent to OEM coil geometry for field re-tubing. |
| Inlet/Outlet Headers | SA 106, SA 335 alloy | Drilled & machined | Feedwater inlet and steam outlet headers, machined to OEM stub patterns and weld preps. |
| Coil Supports & Guides | Alloy steel | Thermal expansion guides | Internal tube support structures accommodating thermal expansion during startup and shutdown cycles. |
| Burner & Combustion | ||
| Burner Assemblies | Gas or oil-fired | High-capacity | Complete burner replacements for natural gas, associated gas, crude oil, and diesel fuel service. |
| Fuel Nozzles | SS or alloy | Various capacity ratings | Atomiser nozzles for oil firing and gas injection nozzles, precision-machined for emission compliance. |
| Ignition Systems | Direct spark or pilot | High-energy | High-energy ignition electrodes, ignition transformers, and pilot burner assemblies. |
| Combustion Air Fans | FD fans | Direct or belt-driven | Forced-draft fan impellers, bearings, seals, and motor coupling components. |
| Feedwater & Controls | ||
| Feedwater Pumps | Multi-stage centrifugal | High-pressure | Replacement feedwater pump assemblies, impellers, wear rings, mechanical seals, and bearings. |
| Control Valves | Globe type | Pneumatic or electric actuator | Feedwater control valves, steam pressure control valves, and fuel metering valves. |
| Steam Quality Monitors | Conductivity-based | Online measurement | Steam quality/moisture measurement instruments for EOR applications requiring 80% quality control. |
| Safety & Relief Valves | ASME Sec I or VIII | High-pressure rated | Pressure safety valves for steam outlet headers and feedwater overpressure protection. |
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 critical OTSG spares are coil tubes (subject to erosion and scaling in high-TDS service), burner nozzles (wear items), feedwater pump internals (high-pressure service wear), safety valves (periodic recertification), and steam quality monitoring instruments (essential for EOR applications).
Yes. We supply spares specifically for EOR/SAGD once-through generators including high-pressure coil tubes, feedwater pump components, and steam quality measurement instruments. We understand the production impact of OTSG downtime and support expedited supply for critical parts.
OTSG coil tubes are typically SA 106 Gr. B or Gr. C carbon steel for standard service, or SA 335 P11/P22 alloy steel for high-pressure or high-temperature applications. For corrosive feedwater conditions, 9Cr-1Mo (P9) or duplex stainless grades may be required.
Yes. We supply parts for both onshore and offshore OTSGs, including compact marine-type units from Aalborg/Alfa Laval and similar manufacturers. Parts are supplied with full material certification for offshore regulatory compliance.
Standard carbon steel coil tubes (SA 106) are typically available within 2-3 weeks. Alloy grades (SA 335 P11/P22) may require 4-6 weeks. For emergency requirements, we can often expedite supply from our global stock network. Pre-bent tubes to OEM geometry may require additional fabrication time.
Share your equipment make, model, and part numbers, we respond within 24 hours.