WATER BATH HEATER
Indirect fired heating for wellhead gas, crude oil, and produced water -- stable bath temperature, no direct flame contact, built for continuous field operation.
Where Water Bath Heaters Are the Standard Field Solution
Water bath heaters are the most widely deployed fired heating technology in upstream oil and gas. Their indirect heating principle -- no direct flame contact with the process fluid -- makes them inherently safe for heating flammable gas and crude oil, and their thermal mass provides a stability that direct-fired heaters cannot match.
Wellhead Gas Heating (Hydrate Prevention)
When high-pressure gas expands across a wellhead choke valve or pressure regulator, the Joule-Thomson effect causes a significant temperature drop. A water bath heater upstream of the choke raises the gas temperature before expansion, ensuring the downstream temperature remains above the hydrate formation curve across all operating conditions.
Gathering Station Gas and Liquid Heating
At oil and gas gathering stations, produced fluid often requires heating before separation to improve water dropout efficiency. Heating the wellstream before the separator train reduces emulsion stability, accelerates oil-water separation, and maintains consistent inlet conditions regardless of ambient temperature.
Gas Pressure Regulation Station Heating
City gate stations and pipeline pressure regulating stations experience Joule-Thomson cooling whenever gas pressure is reduced. Water bath heaters at these stations are a regulatory requirement in cold climates -- preventing freeze-up of the pressure regulator and ensuring stable gas delivery temperature.
Crude Oil Viscosity Reduction
High pour-point crude oils gel at low temperatures. A water bath heater raising the crude temperature above its pour point restores flowability for pipeline transport. Because heating is indirect through an immersed coil, the fire risk associated with heating flammable liquids is eliminated.
Supplier Reference: Sinopec & CNPC HSE Certified
LINSON OIL is a certified supplier with water bath heaters deployed across upstream gathering and processing facilities. Awarded Top 10 Excellent Supplier (2020 & 2021) by Sinopec Northwest Bureau No. 5 Joint Station.
→ View Project ReferencesOperating Principle: Indirect Heating Through a Water Bath
The Indirect Heating Principle
A water bath heater consists of three systems operating in sequence: a combustion system (fire tube and burner), a thermal storage system (the water bath), and a heat transfer system (the process coil immersed in the water). The fire tube carries combustion flame and hot flue gases, heating the surrounding water bath. The water bath is maintained at a controlled set temperature (typically 60°C to 90°C). The process fluid flows through a coil fully immersed in the water, receiving heat across the coil wall.
Why Indirect Heating Matters
Direct-fired heaters bring a flame into close contact with the process fluid. If heating flammable gas or crude oil, a tube failure can result in an explosion. In a water bath heater, a coil failure releases process fluid into the water bath -- not the combustion zone. The water bath physically separates the flame from the process fluid, providing an inherent fire safety barrier.
Burner and Fuel Train
The burner fires on field gas, eliminating external fuel needs at remote locations. The fuel train includes a pressure regulator, filter, isolation valves, and a solenoid valve controlled by the flame safety system. On loss of flame, the solenoid valve closes automatically, preventing unburned gas accumulation.
Safety Controls -- Standard on Every Unit
- High water bath temp shutdown (prevents boiling)
- Low water level shutdown (prevents fire tube burn-out)
- Flame failure shutdown (solenoid closes instantly)
- High process outlet temp alarm (optional protection)
- Low fuel gas pressure shutdown (prevents unstable combustion)
Engineering Specifications
Detailed technical parameters for standard and high-pressure water bath heaters.
| Parameter | Standard Range | Notes |
|---|---|---|
| Heating Duty | 50 kW - 3,000 kW | Larger duties with multiple units/custom |
| Process Media | Gas / associated gas / crude / water | Low-viscosity standard |
| Process Inlet Temp | -30°C to +60°C | Cold climate service standard |
| Water Bath Temp | 60°C - 95°C (controlled) | Thermostatically maintained; never boiling |
| Thermal Efficiency | 75%-85% (typical) | Per operating load |
| Shell Design Pressure | 0.4 - 1.6 MPa (g) | Low-pressure vessel |
| Coil Design Pressure | 1.6 - 35 MPa (g) | Per wellhead operating pressure |
| Coil Material | Carbon steel / 316L SS / Chrome-Moly | Per fluid corrosivity |
| Design Code | GB 150 / SY/T 0538 | ASME dual certification available |
Coil Design Pressure Guide
- Wellhead gas (high-pressure) 14-35 MPa
- Gas pressure regulation 4-16 MPa
- Gathering station 4-10 MPa
- Crude oil / water heating 1.6-4.0 MPa
* Coil design pressure must match upstream operating pressure.
Standard Supply & Customization Scope
Standard Factory Configuration
- ▪ Shell (water bath vessel) per GB 150
- ▪ Fire tube assembly with natural/forced draft burner
- ▪ Process coil (material & pressure per calculation)
- ▪ Thermostat (bath temperature control)
- ▪ High water temp & Low water level shutdown switches
- ▪ Flame safety control (auto-shutdown on failure)
- ▪ Fuel gas train (regulator, filter, manual & auto valves)
- ▪ Flue gas stack with rain cap
- ▪ Local control panel with indicator lights
- ▪ Saddle supports or skid frame
- ▪ Factory pressure test & Surface treatment
OEM / ODM Customization
Certified Manufacturing. Independent Testing.
In-house execution from material trace to final hydrotest, backed by CNAS lab accreditation.
Pressure Vessel License
A2 & High-Pressure Vessel fabrication, covering shell and high-pressure coils.
ISO 9001 & 3834
Quality Management and specialized Welding Quality Management for high-pressure systems.
Accredited Laboratory
In-house NDT and material testing; results internationally recognized under ILAC MRA.
Material Traceability
Shell plates and coil tubing procured with mill certs. 3.1 certificates (EN 10204) available for high-pressure service.
Welding Qualification
WPS/PQR per GB/T 19869 or ASME IX. High-pressure coils receive full RT on girth welds, PT on socket welds.
NDT Inspection
CNAS-accredited lab performs RT, UT, MT, PT. Accepted by international clients without re-testing.
Independent Hydrotests
Shell and process coil hydrotested independently at 1.25× design pressure. Third-party witness ready.
Functional Testing
Every unit is fired up before shipment. Burner ignition, temp control, and safety shutdowns verified.
Export Preparation
Nozzles blanked, firebox sealed, standard export crating. Full dossier (invoice, test records, certs) supplied.
Heating Equipment Operating Across the Upstream Industry
Tell Us the Fluid, the Pressure, and the Temp Rise.
Water bath heater sizing requires your process fluid, flow rate, inlet and outlet temperatures, and coil design pressure. Send us these parameters and our engineers will come back with a heater duty calculation and recommended configuration.
Free Engineering Resource
Submit your parameters and receive within 1-2 business days:
- Heater duty calculation & recommended size
- Coil material recommendation
- Relevant project reference match