Ceramic positioning pins are extremely wear-resistant, in particular against very hard steels such as Usibor. They are also electrically insulating and have a non-stick effect against weld spatter. The ceramics extend equipment service lives by a multiple when compared to that of steel or hardened steel locating bolts. Users acquire significant benefits in quality assurance since the improved wear resistance ensures constant tolerances of the welded body components for many years.
Weld-centring pins/welding nuts
Ceramic weld centring pins have much longer service lives than steel ones. Once again, the ceramic stands out with its high temperature resistance at consistent hardness, extraordinary flexural and impact strengths. It also prevents adhesion of weld spatter. First and foremost, however, it is a natural electrically insulator.
Once again, the predominant arguments in favour of ceramics are quality and cost savings. Weld spatter “sticks” to the pin quickly in projection welding with steel pins and plastic insulation. This is all it takes to impair the process. What is even worse is that the weld spatter will burn the insulation. This breaks electrical insulation and creates shunts. Current will then not only flow through the boss nut but also through the pin, which significantly influences weld quality.
The longer service life considerably saves on costs. Downtimes from pin changes and maintenance are quite expensive.
This is not even considering the costs caused by complaints due to faulty welds.
Centring sleeves for welding screws/bolts
The same issues known from welding nuts occur in bolts and screws as well. Electrical insulation, spatter resistance, and wear resistance are important once again.
Ceramic gas nozzles of silicon nitride are characterised by very long service lives. In contrast to copper nozzles, they can be cleaned of weld spatter easily. This generates an enormous cost benefit since ceramic nozzles can be used for up to 15 weeks straight.
Manufacturers of cooking pots or high-quality metal buckets attach the handles by resistance welding. Since welding projections should not be pressed into the pot/bucket to be visible from the inside, silicon nitride thrust pieces are used. Ceramany customises thrust pieces to match the product diameter.
Pipes are often closed by inductive welding in their last production step. Here, at the latest, welding rollers that do not disturb the induction field, i.e. that are not electrically conductive, must be used. Silicon nitride, which can be produced with excellent surface quality and very good dimensional stability, is ideal for this application.
Welding is used in the food industry as well. Coffee pads and the lids of yoghurt pots, as well as any other packaging with a lid will be welded. Because of this, the sealing head insulation must be accordingly temperature-resistant, while also withstanding hot steam in order to survive the cleaning process. Zirconium oxide is best for this application.
A temperature-stable and pressure-resistant base is required for welding cable ends. Silicon nitride substrates work almost wear-free in this application.
The soldering pad generally has the same function as the welding pad. Silicon nitride is resistant to the solder, temperature- and wear-resistant. Such pads are used, for example, when soldering carbide teeth onto saw blades.
Further applications in welding technology include:
- Wire guides
- Spatter protection/weld pool backing
- Gas supply units
- Gas distributor
- Thermal insulation
- Electric insulation