Presspaper & Pressboard

Depending on the type of cellulose, fibre preparation and machine settings, Krempel offers various types of presspaper and pressboard with very special qualities. These cellulose products are manufactured on special paper machines; we have one of the world's largest production facilities for continuously manufacturing presspaper as well as state-of-the-art presses for the production of pressboard. The composition and properties of presspaper and pressboard for electrical insulation are standardised according to IEC 60641. However, we also manufacture customized special types.

During the production of pressboard, the wet paper web is wound onto the so-called format roller in several layers and then couched. Once the required number of layers or thickness has been reached, the "wrap" is cut. The resulting raw pressboard is automatically transported into a high-performance press, which ensures good wet densification and dewatering. Depending on the type of pressboard, it is either dried in a multi-level heating press under pressure (POWERBOARD AK type) or using pressureless drying with subsequent calendering (types PSP 3050, PSP 3051).

Our portfolio of pressboards:

Type	IEC designation	Description
POWERBOARD AK	Typ B.3.1A IEC 60641-3-1	Hot-pressed, dimensionally-stable pressboard, natural colour
POWERBOARD AK CG / PHG	Typ LB.3.1 A IEC 60763-3-1	Laminated pressboar made from Powerboard AK
PSP 3050	Typ B.2.1B IEC 60641-3-1	High-density, calendered pressboard, natural colour
PSP 3051	Typ B.4.1 IEC 60641-3-1	Mouldable calendered pressboard, natural colour
PSP 3010	Typ B.6.1A IEC 60641-3-1	High-density, calendered pressboard, orange-brown

Available dimensions for pressboard:

Thickness pressboard:	0,8 - 8,0 mm
Thickness laminated pressboard:	9,0 - 120 mm
Format POWERBOARD AK:	2.200 x 4.200 mm
Format of calendered pressboard:	1.000 x 2.000 mm

Other formats and individual solutions on request.

In the production of presspaper, the prepared cellulose fibres are placed on several circular screens (screen cylinders) arranged one behind the other on our paper machines and the wet paper web is couched to form the wet, multi-layer presspaper. Following this sheet formation process, the fibre structure is mechanically dewatered, dried and smoothed and compacted between the rollers of our supercalenders. This gives the presspaper its required thickness and density and thus its good mechanical and electrical properties.

Our portfolio of presspaper and DPP:

Type	IEC designation	Description
PSP 3055	Typ P.2.1A IEC 60641-3-2	High density calendered presspaper with high chemical purity, natural colour
PSP 3055 SL	Typ P.4.1A IEC 60641-3-2	Low density calendered presspaper with high chemical purity, natural colour
Nomex®910	-	High-temperature resistant presspaper reinforced with Nomex® aramid fibres
KREMPEL-DPP	-	3055 SL presspaper or Nomex®910 with partial resin coating in the B-state
PSP 3040	Typ P.6.1B IEC 60641-3-2	Calendered presspaper for dry applications, grey-black

Available dimensions for presspaper:

Thickness pressboard:	0,075 - 1,0 mm
Thickness DPP:	0,05 - 1,0 mm
Parent roll width:	max. 2.100 mm
Cut narrow rolls:	≥ 6,0 mm

Other format products and individual solutions on request.

Layer insulation, core insulation, winding insulation
Insulation cylinders
Mouldings, bars and cooling channels
Spacers and washers
Printing plates, printing and shielding rings
Dielectrics in capacitors
Punched and folded parts

For applications in liquid-filled transformers we produce a wide variety of presspaper and pressboards, which are also process into presspaper with diamond-dotted resin coating (DPP), corrugated board, laminated pressboard, ladder ducts and ladder grids.

All-round insulation, intermediate insulation
Groove linings
Stator and rotor end discs
Coilformers
Punched and moulded parts

For the insulation of motors, coils and other electrical devices where the presspapers and pressboards are not impregnated with a liquid dielectric, we produce a wide range of different types of presspaper and pressboard, some of which have tailor-made properties for special applications.

CutGreen punching strips and punching boards are ideal for all types of punching and drilling processes where a stable base pad is needed.

In addition to our standard version, we also offer a special "Extra" variant for higher mechanical load capacity.

All CutGreen punching and drilling pads are made from 100% unbleached sulphate fibres and water, a truly natural product, which is therefore easy to recycle.