Concora Test is one of the testing methods that widely used in Corrugating Medium. There are two kinds of concora tests; CFC (Concora Fluted Test) which mostly influenced by sheet MD strength and CEC (Concora Edge Crush), which mainly influenced by sheet CD strength.
Since the Concora flat crush is mostly effected by machine direction strength and the Concora edge crush is most effected by the cross machine direction strength, anything we do which increases M.D. of C.D fiber orientation will help one test and hurt the other.
Described below is some ideas on how to improve the regular CFC test but also includes some information on how to improve the CEC test:
Since the Concora flat crush is mostly effected by machine direction strength and the Concora edge crush is most effected by the cross machine direction strength, anything we do which increases M.D. of C.D fiber orientation will help one test and hurt the other.
Described below is some ideas on how to improve the regular CFC test but also includes some information on how to improve the CEC test:
- OCC furnish quality
- Minimize OCC contaminants; soft whites, core stock scrap, Asian OCC, cuttings from box plants using primarily recycled fiber in OCC, waxed boxes
- Minimize degradation of OCC by exposure to water and to sunlight - Refining
Refine incoming stock at neutral to alkaline pH
Do a low intensity refining
Maximize consistency through refiners
Run refiners in series - Wet-End section
Get optimum MD/CD orientation across machine width
Run at lower headbox consistency - Press Section
Maximize Press loading, especially after the first press - Dry end Section
Run at maximum basis weight (reasonable)
Run with lower sheet moisture - Chemical Additives
- Increase cationic starch dosage (careful to over-cationization potential). Change to Amphoteric starch and we will be free to add more dosage without over-cationization potential.
- Use Dry Strength Additives; Glyoxylated PAM will normally increase concory by creating covalent bond.
