Density (also known as ‘bulk density’ for felts) is a measure of the firmness of a felt and is calculated by dividing the mass [kg] by the volume [dm³] (the resulting units are kg/dm³ or g/cm³). This firmness is divided into four classes (soft, medium, firm, hard) and specified in more detail.
DIN 61200 specifies the precise firmness descriptions and the tolerances for these. Other densities have been summarised in a separate document for you.
Density [kg/dm3]=Mass [kg]Thickness [mm] * Length [m] * Width [m]
Firmness descriptions in accordance with DIN 61200
|W1 0,08||M1 0,18||F1 0,32||H1 0,52|
|W2 0,10||M2 0,20||F2 0,36||H2 0,56|
|W3 0,12||M3 0,22||F3 0,40||H3 0,60|
|W4 0,14||M4 0,25||F4 0,44||H4 0,64|
|W5 0,16||M5 0,28||F5 0,48||H5 0,68|
Deviations are possible depending on quality and firmness
The standard dimensions of our products are:
PRODUCTS IN ROLL FORM: Thickness: 1 – 30 mm Density: 0.10 – 0.52 g/ccm Width: Approx. 120 to max. 200 cm
SHEETS AND BLOCKS: Thickness: 0.8 – 150 mm Density: 0.10 – 0.68 g/ccm
ENDLESS BELTS: Thickness: 3 – 15 mm Density: 0.40 – 0.56 g/ccm
TUBES: Thickness: 3 – 50 mm Density: 0.42 – 0.56 g/ccm