Glossary
Alternative cleaning
Water lance
Also known as water lances, hydraulic lance.
A water lance is a handheld or fixed water-jet cleaning device used either during boiler outages (handheld manual variant) or, in fixed mechanised designs (notably from Bergemann), during operation on selected slag-melt zones. The fixed mechanised water lance differs from a water cannon primarily in lance length, reach and shot pattern — both technologies rely on thermal-shock cracking of slag.
Where water lances are used
- Outage cleaning — handheld lances projecting water into boiler internals after shutdown
- Slag-prone zones during operation — fixed mechanised lances on coal-fired boiler furnace exits and reheater inlet zones
- Cement-plant preheater cleaning — manual water-lancing during planned outages on kiln-inlet build-up
Sonic horns reduce the frequency of water-lancing campaigns by preventing the accumulation that water lances are deployed to remove.
Related terms
Related terms
- Water cannonA water cannon projects a high-pressure water jet onto boiler waterwalls to crack slag deposits by thermal shock. The standard cleaning tool for furnace slag, with care for tube fatigue.
- WaterwallWaterwalls are panels of vertical evaporator tubes welded into a gas-tight membrane that line the furnace. They absorb radiant heat and produce most of the boiler's steam.
- Manual lancingManual lancing is operator-performed cleaning using handheld rods, lances or jets. Labour-intensive, HSE-burdened; the cleaning method of last resort in most industrial settings.