Wibrox® special brushes for Ferret machines
Wibrox® brushes have been developed and used for many years to cope with the extreme workload they face in boiler tubes. For example, in a boiler with 500 tubes, each 5 metres in length (and so 10 metres in all, back and forth), a brush will travel a total of 5,000 metres, all the time delivering 32 brushing stokes per second!
The brushes are available in sizes ranging from 26 mm to 213 mm in diameter and are suitable for all boilers on the market. We can also provide special purpose brushes. As the Ferret machine oscillates rather than rotates, it will also work well with rectangular brushes.
Most of the brushes are available in varying degrees of hardness: soft, normal, hard and very hard. The brushes are designated according to their diameter, with an affix indicating whether the brush is soft (M), hard (H), hard with double stem (HD), very hard (MH) or thinly wound for soft-filled tubes (GD). The normal brush designation has no affix. Thus Wibrox® 72 is a normally hard brush of diameter 72 mm, and Wibrox 72 HD a hard brush with double stem and a diameter of 72 mm.
For tubes with a lot of soot and ash deposits we have developed a special type of brush, GD, which can pass through a tube without piling up all the soot and ash in front of it. After going through a tube with the GD brush, you can then run through it again with a normal brush.
The type of brush which is suitable for a specific boiler depends amongst other things on the fuel being used in the boiler and also on the type of coating inside the tubes. We will be happy to help by discussing with you which brush is needed for the best desooting results in your particular boiler.
The first thing we need to know is the inside diameter of the tube. Steel tubes are designated by their outside diameter and wall thickness, and these measurements can often be found on drawings relating to the boiler. For example, 76.1 x 4 refers to a steel tube with an outside diameter of 76.1 mm and a wall thickness of 4 mm, which will mean an inside diameter of 68.1 mm.
Desooting with Ferret machines and Wibrox® brushes is based on the principle that the brush diameter should be several mm greater than the inside diameter of the tube. It is therefore very important to know the exact inside diameter so the machine can operate at speed and deliver optimum results.
The illustration below shows the different types of brush available with a diameter of 72 mm.