A Guide to Choosing the Right Tube Cleaning Brush When Cleaning Heat Exchanger, Chiller, and Boiler Tubes
A brush is a brush, is a brush, right? Wrong!
For maintenance professionals, cleaning tubes in heat exchange equipment is as common as the sun rising and seeing each day. While there can be numerous ways to clean the tubes of a heat exchanger, chiller, or boiler, one of the more common methods is utilizing a brush connected to a tube cleaning rod or flexible shaft on a machine. And just like selecting the suitable cleaning method for your needs is essential, so is selecting the correct brush. Using the right brush will ensure effective and efficient cleaning, reduce the risk of tube damage, and prolong the equipment's lifespan.
In this guide, we will look at the top considerations for choosing the right brush:
- Tube diameter
- Fouling type
- Tube material make-up
- Tube type (enhanced or smooth bore)
Understanding Tube Interior Diameter (ID):
The interior tube diameter or tube ID, for short, is critical when selecting a brush for cleaning heat exchanger, boiler, and chiller tubes. Using the wrong brush size can lead to ineffective cleaning, tube damage, damage to your cleaning equipment and increased maintenance costs through poor results. For instance, using a brush that is too small for a larger diameter tube will not effectively clean the tube, while using a too-large brush may damage the tube's interior construction, especially with enhanced tubes. Consider these points when choosing the proper tube ID.
- Heat exchanger tubes typically have smaller inner diameters, ranging from 3/8" to 1".
- Chiller tubes can have larger inner diameters, ranging from 1/2" to 1-1/4".
- Conversely, boilers usually have the largest inner diameters, ranging from 1-1/2" to 2-1/2" or even larger.
*Fire tube boilers are usually sized by the O.D (outside diameter)
It is important to note that these ranges are general and can vary based on the specific application and manufacturer. Make sure to reference your heat exchanger user manual or measure (twice!) before choosing your brush size.
PRO TIP: On heat exchanger and chiller tubes, when using a softer nylon brush, consider using a brush size 1/16” larger than the ID. Use a dual diameter brush, especially with internally enhanced tubes (sometimes called rifled tubes). Doing so can help increase the cleaning performance of the tube surface as it will be able to clean the grooves of the tube walls.
Understanding Tube Fouling:
Tube fouling is a fancy way to say the type of deposit or material left inside the tube after heat exchange. The type of fouling that accumulates in the heat exchanger, boiler, and chiller tubes is a crucial factor to consider when selecting a brush for cleaning. Different types of fouling require different brush types. Using the wrong brush type can lead to ineffective cleaning and significant tube damage.
- Nylon brushes:
- Ideal for removing soft and light deposits like mud, silt, and biological growth in heat exchanger tubes.
- Suitable for removing microbiological growth in chiller tubes.
- Brass brushes:
- Useful for removing scale and sediment in heat exchanger tubes.
- Suitable for removing rust and debris in chiller tubes.
- Stainless steel brushes:
- Effective for removing tough deposits such as scale and sediment in ferrous heat exchanger tubes.
- Suitable for removing rust and debris in ferrous chiller tubes.
- Wire brushes:
- Effective for removing scale, sediment, rust, and debris in ferrous heat exchanger tubes.
- Suitable for removing soot, ash, and slag deposits in boiler tubes.
It is essential to understand that fouling can vary in type and severity depending on the application.
PRO TIP: Sometimes soft and hard fouling may be present, requiring different brush types. Make sure to take a close look at the fouling present prior to choosing the brush materials.
Understanding Tube Make-up:
The material or make-up of tubes is a critical factor to consider when selecting the appropriate brush for cleaning. While often classified as either ferrous or nonferrous tubes, we wanted to go a step further and look at specific metals.
Copper is commonly used for tubes of heat exchangers and chillers. For cleaning copper tubes, typically, the following brush types are recommended:
- Nylon brushes
- Brass brushes
In addition to copper, stainless steel tubes are commonly used in heat exchangers. For cleaning stainless steel tubes, typically, the following brush types are recommended:
- Nylon brushes
- Stainless steel brushes
In boilers, carbon steel tubes are commonly used. For cleaning carbon steel tubes, typically, the following brush types are recommended:
- Steel spring filled or wheel brushes
- Brass brushes
- Stainless steel brushes
What We Have Learned:
Selecting the correct brush for cleaning the tubes of an industrial heat exchanger, chiller, or boiler is a crucial step in the cleaning process to ensure proper cleaning. The interior tube diameter (I.D.), the type of fouling, and the tube material or makeup are often the most critical factors to consider when selecting a brush. Using the right brush will ensure effective and efficient cleaning and prolong the lifespan of the equipment.
Goodway Technologies is here to help. We provide an array of tube-cleaning brushes suitable for most applications. If you are still unsure what brush suits your application, contact one of our experts today.
Did You Know? Sometimes, using a brush might not be the most suitable choice for the tubes you are trying to clean. Heavily scaled tubes or those in complex piping designs may benefit from more industrial cleaning heads or chemical descaling. Learn more about that at our descaling solution page.