Product Overview
The WNS Series Low-NOx Gas-Fired Steam Boiler with Condensing Economizer is a high-efficiency packaged boiler designed to provide stable saturated steam for clean-fuel industrial applications. Featuring a horizontal three-pass wet-back fire-tube structure, a corrugated furnace, and an integrated condensing economizer, it delivers reliable performance, reduced fuel consumption, and long service life. With a low-NOx burner and fully automatic smart control system, it ensures clean combustion, safe operation, and dependable steam supply across a wide range of industries.

Product Structure Drawing

Key Advantages
The integrated economizer and condenser recover sensible and latent heat from flue gas, achieving up to 105% thermal efficiency (LHV basis) under suitable conditions and significantly reducing fuel consumption.
Built with 09CrCuSb (ND steel) spiral-finned tubes for enhanced acid dew-point corrosion resistance. The top-mounted design saves installation space and facilitates condensate drainage.
Equipped with a high-performance low-NOx burner for stable, efficient combustion and reduced emissions, with configurations available to meet stringent local environmental regulations.
The three-pass wet-back structure and fully corrugated furnace maximize heat transfer, accommodate thermal expansion, and enhance structural durability for reliable steam generation.
The compact, integrated structure and top-mounted heat-recovery system minimize installation footprint, simplify on-site installation, and reduce boiler-room construction costs.
Fully automatic combustion, pressure, and water-level controls ensure stable steam output and reduced operator workload, while comprehensive safety interlocks provide reliable operational protection.
Typical Applications
Reactor Heating、Distillation、 Evaporation、Drying、Stripping、Tank Heating 、Cleaning
Rubber Vulcanization、Compounding、Mold Heating、Process Water Heating、Equipment Cleaning、Drying
Technical Specifications
| Item | WNS2 | WNS3 | WNS4 | WNS5 | WNS6 | WNS8 | WNS10 | WNS12 | WNS15 | WNS20 | ||
| ~1.25–Q | ||||||||||||
| Rated evaporation capacity | t/h | 2 | 3 | 4 | 5 | 6 | 8 | 10 | 12 | 15 | 20 | |
| Rated working pressure | MPa | 1.25 | ||||||||||
| Rated steam temperature | °C | 194 | ||||||||||
| Feed water temperature | °C | 20 | 104 | |||||||||
| Thermal efficiency | % | ≥ 105 | ||||||||||
| Full water capacity | L | 5800 | 6800 | 8800 | 8900 | 10000 | 14000 | 15600 | 16500 | 18000 | 22100 | |
| Steam outlet | DN | 65 | 80 | 100 | 125 | 150 | 200 | |||||
| Feed water | DN | 40 | 50 | 65 | 80 | |||||||
| Pollution discharge | DN | 40 | 50 × 2 | |||||||||
| Natural gas | Nm³/h | 142.5 | 213.6 | 285.6 | 356.5 | 427.8 | 574.4 | 713 | 855.6 | 1070 | 1426 | |
| Overall size | Length | mm | 4550 | 5050 | 5300 | 5600 | 6300 | 6900 | 7600 | 7800 | 8000 | 9000 |
| Width | mm | 2100 | 2150 | 2250 | 2350 | 2420 | 2650 | 2700 | 2950 | 3400 | 3500 | |
| Height | mm | 2350 | 2500 | 2850 | 3020 | 3300 | 3350 | 3450 | 3550 | 3600 | 3600 | |
| Weight | T | 7.41 | 10.2 | 11.6 | 13.8 | 18.5 | 21.12 | 26.64 | 31.2 | 39.2 | 45.4 | |






