---
title: "Water lance"
description: "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."
canonical_url: "https://sylio.co/glossary/water-lance"
last_updated: "2026-06-28T02:29:23.976Z"
---

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](/glossary/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](/glossary/sonic-horn) reduce the frequency of water-lancing campaigns by preventing the accumulation that water lances are deployed to remove.

## Related terms

- [Water cannon](/glossary/water-cannon)
- [Waterwall](/glossary/waterwall)
- [Manual lancing](/glossary/manual-lancing)