Electricity/Electroplating Shop

For the construction of measuring instruments, the workpieces frequently need surface treatment, e.g. for the following reasons:

• corrosion protection
• raising of conductivity
• dimensional reworking of worn components
• optical or decorative aspects.

According to the task to be carried out, the following processes are available:

Electroplating with gold, silver, chromium, nickel and black nickel as well as copper. Gold plating can also be carried out by chemical means (without current) by a so-called dip gold-plating procedure..

Anodizing is an electrochemical oxidation of the surfaces, especially of aluminium and aluminium alloys. It is possible to blacken the anodized layer.

Bronzing of iron and iron alloys offers corrosion protection which is limited in time..

Particularly difficult concave (internal) forms and structures on workpieces can be obtained by galvanoplastic vapour deposition of copper on a core of special steel (reusable) or plastics. The outside form of the cores is obtained by the well-known cutting procedure and is identical with the inside form of the component fabricated by electroforming. Due to the different thermal expansion coefficient, special steel cores are easy to remove. Plastic cores which have been made conductive prior to electroforming by spraying a very thin silver coat can be removed by chemical means.

The procedures include an extensive preliminary and aftertreatment of the workpiece surfaces in solvent, hot and electric degreasing and pickling baths as well as in baths for the removal of coats applied by electroplating and to produce precipitation layers, e.g. in electroforming. All baths need to be permanently monitored by analysis, documented and maintained

To save drinking water, to constantly maintain a good water quality and to avoid toxic waste water entering the sewage system, the Electroplating Shop has a rinsing water treatment system consisting of a recirculation system with filters and ion exchangers. Due to the periodic regeneration of the ion exchangers, the collecting tanks for the alkaline and acidic reclaims to be detoxified in the batch treatment system and to be prepared for heavy metal precipitation are filled. The sludge forming during electroplating is retained in a filter press and must be disposed of as hazardous waste. After the mandatory limiting values for heavy metals and other toxicants have been checked by analysis, the filtrate is discharged into the sewer system. These internal checks are supplemented by sewage checks carried out at regular intervals by the municipality of Braunschweig..