Electropolishing of Flexible metal conduit,Flexible electrical conduit ,Stainless steel Flexible conduitNew Technology
First, the characteristics of
1, polishing liquid is non-chromic acid, with the current requirements of environmental protection, saving environmental protection investment in equipment and waste water treatment costs. 2, polishing current density of small, low voltage, power consumption than traditional low-technology for more than one times. 3, polished and efficient, good quality and can be thrown a few minutes to mirror bright. 4, polishing liquid long life, easy maintenance and management.
Second, polishing fluid composition and operating conditions
Concentrated phosphoric acid (specific gravity 1.74) 500ml / L 870g / L concentrated sulfuric acid (specific gravity 1.84) 400ml/L736 g / L LQ-62 additive 50ml/L52.5 g / L of water 50ml / L 50 g / L temperature of 50-75 ℃ best 60-65 ℃; anodic current density, DA6-15A/dm2 best 10-12A/dm2 voltage 5-8 V; polishing time 3-5 minutes; cathode materials: lead or lead alloy; cathode area: anode area: 2-3:1
Third, slotting steps
LQ-62 additive is a surfactant, in its use of the early Electropolishing produces a large number of the bubble, so polished and the polishing liquid surface at the top of the distance between the trough should not be ≤ 15cm. For an accurate calculation will be prepared Electropolishing fluid volume, and then in accordance with the composition of the slurry to the polishing solution by adding the following order of each component by adding polishing bed.
1, inject the necessary water. 2, by adding the required amount of phosphoric acid. 3, remember sulfuric acid diluted with water will release a lot of heat, the sharp increase in solution temperature while stirring add the edge, when the temperature rose to 80 ℃ should be stopped to add, after cooling solution to be added to further increase until all finished. 4, by adding the required number of LQ-62 additives, stirring side edges add, add, after thorough mixing to ensure uniform mixing.
Fourth, process
Chemical degreasing → water washing → Baptist acid (1-2% sulfuric acid solution) → → Electropolishing three counter-current washing → Baptist alkali (5% sodium carbonate solution) → water washing → drying or drying
V. Bath maintenance and additional
1, stainless steel hose before entering the finishing chute as far as possible will be left on the surface of the water removed, due to excessive moisture entrainment workpiece may cause serious polishing surface pitting, localized erosion caused by the workpiece scrapped.
2, in the electrolytic polishing process, as the anode of stainless steel hose, the amount of iron, chromium changing for the metal ions into the slurry within the cathode surface in the deposition. With the polishing process, the metal ion concentration increasing, when reached a certain value, these metal ions to phosphate and sulfate forms from precipitation within the slurry, sedimentation in the trough at the bottom of polishing. To this end, the slurry must be regularly filtered to remove the solid precipitates.
3, in the polishing process is running trough, with the exception of phosphoric acid, sulfuric acid continuously consumed outside the electrolysis of water due to evaporation and loss, in addition, high-viscosity slurry entrainment losses have been workpiece, polishing liquid decreasing surface, need to be polished to Groove additional fresh slurry and water. 4, the polishing slurry, without accounting for the original pre-1.68, running in the groove polishing process, the proportion of slurry should be controlled in the 1.68-1.72 range. Slurry weight and viscosity is too high on polishing liquid water content less than high levels of phosphoric acid or sulfuric acid content is low; the other hand, the proportion of slurry is too low, indicating high water content slurry. Often measured by the proportion of the proportion of slurry is a simple and effective means of control.
5, in the conditional case, the best regular analysis of the acidity of slurry, phosphoric acid and sulfuric acid content.
VI, equipment requirements
  Electropolishing normally liquid mineral acids and higher temperature operation, so polished chutes, wash trough, cathode, heating coil and the exhaust device must be made from corrosion resistant slurry material.
1, polyethylene, polypropylene, polyvinyl chloride, epoxy and fiberglass-lined steel trough of the above materials can be used for Electropolishing trough.
2, electrical heating or steam heating coil may choose to use the following materials:
⑴, coil PTFE: polytetrafluoroethylene tube-type heat exchanger for steam heating. PTFE electrical heating pipe for electric heating. Although PTFE coil prices but long life and high power neutral.
⑵, pure lead or lead-antimony alloy coil: pure lead or lead-antimony alloys Electropolishing can be used as a steam heating coil. Coil to increase the service life, in the slurry liquid and air at the junction should also lead thickening.
⑶, quartz electric heating tube.
3, Rack: Titanium linked with the outer coating of copper sol linked with the longest service life. Due to the polishing liquid is non-chromic acid, phosphor bronze can also be used for linking.