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Hydro Cleaning of Pin Tube Elements

Boiler Services.
Many oil-fired boilers feature Pin tube elements as the convection part. These boilers are designed to have a high flue gas velocity trough the pin tube elements, in order to keep the heat transfer area clean.
If soot deposits are accumulated on the heat transfer surface, this will result in less convection heat is transferred to the water/steam and decreasing the efficiency of the boiler.
Normally this is shown as higher flue gas temperature and increasing pressure loss over the boiler.
It is impossible to give an exact interval for when the pin tube elements should be cleaned. As this depends on various factors such as oil quality, burner adjustments and operation load of the boiler.
A visual inspection inside the boiler is a good method to check if cleaning of pin tube elements is necessary.

Other methods to check if cleaning is needed:
Flue gas temperature has increased compared to normal flue gas temperature of the boiler. Total pressure loss of boiler has increased compared to normal pressure loss for a clean boiler.
Hydro cleaning of the pin tube elements is an effective method for removal coating and soot deposits. The effective cleaning result is by combining the soaking of pin tube elements with compressed air in the washing water.
If the amount of soot deposit on the pin tube elements is light it can be enough to only leave the pin tubes soak for a few hours then adding the turbulent compressed air to the water to loosen the residues and deposits.
Depending of the amounUdegree of coating or deposits it may be necessary to add chemicals to the washing water.
The Hydro cleaning unit allows for all pin tubes elements to be cleaned simultaneously, and keep the furnace room dry during cleaning.

Hydro cleaning procedure
The Hydro cleaning unit is easy to use. When boiler has allowed to cool down access the furnace room by removal of burner. Install the cleaning plugs to the bottom of the pin tube elements by tighten the screws. Connect each cleaning plugs to the collector unit.
Fill up the pin tube elements with washing water trough the water inlet valve in collector unit. Allow for a steady flow of compressed air trough the collector unit to be injected around the pin tube elements.

The step by step procedure - open as PDF file - Copyrights - all rights reserved