Pressboard
Pressboard , even pressboard called, is a material group consisting of pulp, which no binder is added.
Manufacturing
A moist paper web is produced from cellulose using a paper machine. However, this is not dried in the original thickness as in paper production and only then wound up. Instead, the still moist paper is wound up until the desired thickness of the end product (0.1 mm to 8 mm) is reached. The roll is removed and cut, then flattened, pressed and dried. This results in a very thick, stable, paper-like material. The dried material can also be compacted by rollers and structured on the surface by calendering.
processing
Pressboard can be processed with punching tools, but also drilled, sawed, milled and filed. It can be moistened and then becomes somewhat malleable, for example by roller burnishing.
use
Pressboard is used in particular for electrically insulating components. The insulating and supporting elements of the coil windings of power transformers are often made of pressboard, as are insulation layers and spacers in electrical machines and household appliances.
Pressboard is also processed into - often orange-brown - book covers or book spines, as well as used in model making.
disposal
As pressboard consists of cellulose and does not contain any binding agents, it is easily biodegradable . This does not apply to built-in transformers and other components that have been soaked with insulating oils or other chemical substances.
supporting documents
- ↑ http://www.krempel-group.com/deutsch/home/produkte/elektroisolierstoffe/pressspan/powerboard-ak-fuer-leistungsstransformatoren.html
- ↑ DIN EN 60641-3-1: Pressboard and rollboard for electrotechnical applications - Part 3: Regulations for individual materials - Sheet 1: Requirements for pressboard.