Metal seals and sealing strips, which are used in turbines, have numerous advantages. They operate contact-free and, therefore, without wear, require little maintenance and increase efficiency.
Which sealing strip is ideal for which system depends on various aspects. The first decision to make is always the choice of material: seals made of stainless steel, brass alloys or aluminium. All of our sealing strips are designed for extreme operating conditions, such as high rotational speeds or high temperatures. Nevertheless, each material has different properties.
Brass is a copper alloy with a zinc content of up to 40 percent. The melting point of this alloy decreases when the zinc content increases; this is usually around 900° Celsius.
The advantages of making a brass seal are how easily the material can be moulded, the non-magnetic property and the high corrosion resistance. However, the many positive properties come with a price: as a general rule, brass sealing strips are usually more expensive than those made of aluminium or stainless steel.
Being a soft light metal, aluminium is well suited for sealing strips because it is easy to mould and thus adapts ideally to the components. Aluminium offers very good thermal conductivity, while the melting point is around 660° Celsius. It is, therefore, better suited for seals that work at low temperature and offers lower thermal insulation it is, however, relatively inexpensive.
Other positive aspects of aluminium seals are the lack of magnetic properties and the good corrosion resistance. When in contact with air, aluminium sealing strips form a thin layer of aluminium oxide on the surface, which protects against further corrosion.
Stainless steel is the best-known steel alloy available. In addition to the corrosion resistance, the high melting point stands out in particular. At around 1500° Celsius, it enables the use of stainless steel seals even under extreme temperature conditions. In addition, stainless steel has a high break strength.
We offer sealing strips and caulking wires both made of different metals and also in different shapes. This enables us to adapt our seals ideally to your needs. Customised designs are no problem for us – for both the labyrinth seals themselves and for the sealing strips.
We can make customised combinations of various metal sealing strips to achieve ideal results.