Manufacturing types

Spiral brushes

Spiral brushes are the best you can get in terms of price(reusable body),maintenanceandmechanical performance and efficiency.

The manufacturing flexibility allows to obtain every possible combination between size, density, trim length and filling material, making it very versatile in order to perform every type of surface treatment.

Maximum and minimum dimensions

Diametro esternoA401-5/8100039-3/8
Outer diameter
Diametro internoD121/250020
Inner diameter
Passo (densità)P53/16702-3/4
Pitch (density)

The coils of the spiral brush may be wound up closed to or distanced.
The fill density of the brushing surface is determined by the winding pitch and by the number of coils wound onto a body.

High density (closed coils)

Medium density

Low density

Material will be moved out according to the rotation direction and to the winding orientation that can be:

Right-handed (standard)


Convergent/divergent to the center

Rotational speed, strip type and size

Strip brushes forming the spiral brush can be Normal (N) or Double band (G) according to the required filling density and peripheral speed. Normal strip is recommended for spirals working at surface speed lower than 15m/s – 2955ft/min; double-banded strip can withstand higher speed, up to 20m/s – 3940ft/min.

Assembled bases and winding minimum diameter

Diametro minimo / Minimum diameter
BaseTipo strip Acciaio / SteelInox / S-Steel
mminchStrip typemminchmminch

Assembly methods

Spiral Brushes can be wound up and properly assembled to a core that can be either a solid shaft or a tube. The choice between the two systems depends on application and size of the brush.
SIT Technical Office will be at customer’s disposal for studying the the most appropriate strip and mounting for each specific application



Body mounted spiral

The brush, with closed or spaced coils, is mounted directly onto the rotating shaft and both spiral ends are welded. The shaft is re-usable and the brush, once worn out, can be restored in our facility.

A = Outer diameter
D = Shaft outer diameter
LU = Useful length
LT = Total length
T1, T2 = Shaft ends
S1, S2 = Tapered sections length
B1, B2 = Tapered sections diameter
N = Keyway

Interchangeable brush

Closed coils or electrical-welded spiral brushes (or single section wheels) can be fixed through a movable threaded lock nut at one side only matched up with a fixed ring nut on the other side. This makes the replacement very fast and easy

Tube mounted spiral

The brush is mounted on a tube with adapters for coupling with the rotating shaft or with hubs for support and dragging

A = Outer diameter
D = Tube outer diameter
LU = Useful length
LT = Total length
T1, T2 = Tube ends
D1 = Cross hole diameter
N = Keyway

Flanged tube mounted spiral

Spiral brushes or single section wheels can be assembled on a tube and fixed by two flanges (maximal thickness 2mm – 0,078”). The resulting brush is dense and uniform.

Dynamic balancing

The dynamic balancing of the brushes is very important to improve the performance of the surface treatment and to avoid the brushing machine’s stress.
Dynamic balancing is strongly recommended for shaft mounted brushes rotating at high speed. We may perform the balancing (ISO 1940 g. 6,3 as standard) and issue the relevant certificate


A special trimming or even a grinding in case of metal wire generates a perfect cylindricity of the brush with reference to the rotation axis. As a result, the surface of the brush works equally and uniformly on the processed surface.

Shaped roller brushes

Roller brushes can be shaped to comply with special applications and in accordance with customer’s specific requirements. They can be supplied in every type of filament: synthetic, natural, metallic or mixed.
Given the desired performance depending on the profile of the brush, our technical office will provide advice on the best brush for the profile and the filament to be used.

Applications: Cleaning of precast fiber cement runs, cleaning and oiling of molds for corrugated profiles production, applying adhesive film to the tire ply

Spiral rolls advantages

  • Better control of density and stifness
  • Possibility for the customer to choose any brush size
  • Possibility to regulate coils’ pitch
  • Ability to steer the removed material by acting on the windings orientation (right, left or convergent/divergent)
  • Possibility to obtain shaped profiles of the brush upon customer’s drawings
  • Possibility to dispose of worn brushes in our plant and replace them maintaining the core body (LCA management)
  • Higher peripheral speed than stapled set brushes