Inline Pre-Treatment System Solution for P.C. Strandwire with WiTechs Mechanical Descaling Equipment and Electro-Phosphating Line (Ephos®) from STAKU
The wire rod is subsequently propelled by a horizontal wire rod pay-off system in a combined pull-in, bending and straightening machine (BDM-2S / EG). The scale layer is broken and the wire is straightened without cracks. The wire pull in is considerably facilitated by this system concept.
In the following double-head sanding descaler (SEZ-6-302S), the wire will be cleaned and surface pre-treated for the further coating process through two sanding belts with min. 98% cleanliness result.
The next wire preparation step is done by an electro-phosphating plant (Ephos®) Inline from STAKU.
- Wire inlet ø8.0 – 15.0mm
- Wire outlet drawing speed up to 10m/s
- Wire inlet speed up to 1.5m/s
- Wire inlet ø13.0mm
- Finished wire ø5.0mm
- Wire inlet speed 1.2m/s
- Wire outlet drawing speed 8m/s
> Mechanical descaling with inline phosphating at the same drawing speeds as conventionally pickled wires without sacrificing quality.
Horizontal pay-off with coil pusher, model HAF/CVE
Pull-in – bending and straightening with model BDM/2S-EG
Mechanical descaling with double-head sandbelt descaler, model SEZ-6-302S
Advantages of this electrolytic process compared to classical chemical phosphating
- Bath temperature only 45 ° C instead of 80 ° C
- Sludge-free process
- 33% less zinc by replacement with calcium
- 40% lower chemical requirements due to compact and fine crystalline layer
- 3 seconds coating time compared to 7 minutes for classic procedures
- Elimination of highly toxic activation chemicals
- High binding forces prevent shearing during forming
- No waste of old acid, use of economy flushing technology reduces wastewater by 40%
- No after-treatment with soaps, lime or similar
The images under the microscope show the different layer structure.
1st picture: Ephos
2nd picture: Classic zinc phosphating