---
title: "Cyclone dipleg"
description: "The cyclone dipleg is the vertical pipe at the bottom of a cyclone separator that carries separated solids out of the cyclone — either back into a recirculation loop (in CFB boilers and cement preheaters) or into a discharge hopper."
canonical_url: "https://sylio.co/glossary/cyclone-dipleg"
last_updated: "2026-06-28T02:29:33.420Z"
---

The **cyclone dipleg** is the vertical pipe at the bottom of a [cyclone separator](/glossary/cyclone-separator) that carries separated solids out of the cyclone — either back into a recirculation loop (in [CFB boilers](/glossary/cfb-boiler) and [cement preheaters](/glossary/preheater-cyclone)) or into a discharge hopper.

## Pluggage problems

Dipleg pluggage is one of the most operationally disruptive failures in any cyclone system. Once the dipleg blocks:

- Separated solids back up into the cyclone cone
- Re-entrainment into the gas stream rises
- Collection efficiency collapses
- Process flow imbalance follows immediately

A single plugged dipleg can knock out an entire [multi-cyclone](/glossary/multi-cyclone-multiclone) tube or a major CFB combustor.

## Cleaning

[Sonic horns](/glossary/sonic-horn) mounted at the dipleg keep separated material flowing. On large industrial cyclones, multiple horns are sometimes distributed along the dipleg length to address pluggage at any elevation.

## Related terms

- [Cyclone separator](/glossary/cyclone-separator)
- [Multi-cyclone / multiclone](/glossary/multi-cyclone-multiclone)
- [Bridging](/glossary/bridging)
- [Sonic horn](/glossary/sonic-horn)