This is a dual purpose machine.
It can perform the following tests :
- Crease Strength, Crease Recovery and Crease Ratio
- Bending Stiffness
The value of Crease Stiffness is technically important in the folding of carton blanks during their erection and closure, whether this is by hand or by mechanical means. High values of crease stiffness may be associated with an unacceptable appearance of the fold line or its displacement from its proper place in the carton design. The crease recovery (spring back) can result in forces which distort the erected carton or cause stresses to be applied to closures which reduce their effectiveness.
The relationship between board stiffness and crease recovery (spring back) is an important factor in the performance of cartons. Board stiffness is determined by bending a 50mm (2 in.) length of board through a 15° angle.
Crease recovery is determined by holding a formed crease at 90° and measuring the recovery force after 15 seconds. This instrument measures the bending resistance of the board and evaluates commercially formed creases
Bending resistance affects the product performance in many converting operations and end use applications including printing, packaging, etc.