Press simulation method
In the paper machine is water pressed out of the wet sheet. At RISE we have a lab equipment to study different press nips, e.g. roll nips or shoe press nip.
This service is also relevant in: Metrology, Production and manufacturing
Service details
- Service
- Press simulation method of a press nip during papermaking
- Instrument
- Power meters
- Metrology Area
- Force and torque
- Price
- Price on tender
Purpose
The purpose is to show how different fibres or pulps behave during pressing.
If the pressing can be optimized, then less water need to be removed by drying.
Method
Press puls:Programable shape of pulse (e.g. roll press pulse, shoe press pulse). Minimum pulse duration: roll pulse: approx. 10 ms, shoe press pulse: 15 to 20 ms (pulse duration depends on how much deformation is required to achieve a certain deformation in the nip). Max peak stress 10 MPa
Papper samples: Circular samples 60 mm diameter; both laboratory sheets or wet machine sheets (for example if available from FEX trials) can be used.
Grammage: minimum grammage is dependent on initial wet strength of pulp type, practical no limit regarding maximum grammage.
Contacting surfaces: Felts or solids surfaces (simulating rolls), where drainage grid are located below felts. The drainage grid is located in a suction chamber where a low underpressure can be applied.
Movie showing the method with and without rewetting:
http://www.youtube.com/watch?v=GKkwLbf6tXw
Deliveries
Development of dry content before and after drying.